Glossary of Terms and Concepts

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Action research A method whereby part of the purpose of the researcher is to influence or change the participants behaviour.   Examples include the Freud, Thigpen and Cleckley, and Gardner and Gardner core studies. 


Adrenaline A hormone which is produced by the adrenal glands.  Adrenaline increases physiological arousal and causes increase in blood pressure, release of sugar by the liver and other physiological responses related to threat.

In the US the term epinephrine is used instead of adrenaline.


Aggression Negative or hostile behaviour directed towards others or objects.


Altruism Helping others without expecting a reward.  For example, helping a collapsed person on a subway train or writing this glossary.


Ameslan This is an abbreviation of American Sign Language which is the sign language Gardner and Gardner taught Washoe.


Anecdotal evidence Evidence which is not based on research.  


Anthropomorphism Attributing human characteristics to animals.  There is a danger when psychologists (e.g. Gardner and Gardner 1969) study animals as they may falsely see and describe human characteristics in their animal subjects.


Application of psychology to everyday life This is one of the themes of the course.  The examiners may ask you to demonstrate how the findings of a particular core study can be used to explain or describe behaviour and experience in an everyday situation.  For example, we could explain the behaviour of a football referee in terms of their uniform and the role they adopt using the Zimbardo study.


Approaches in psychology There are  five main approaches in the course.  Cognitive Psychology, Developmental Psychology, Physiological Psychology,
Social Psychology and Individual Differences.


Arousal This is a physiological state whereby the body is ready for action.  The sympathetic division of the autonomic nervous system is activated and can involve increasing in blood pressure, heart rate, blood sugar level, respiration rate, and blood flow to the muscles and brain, with an accompanying decrease in blood flow to the skin. 


Arousal: Cost Reward Model

Piliavin et al. developed this model to explain why people do and do not help in emergency situations.

They argue that the observation of an emergency situation creates an emotional arousal in bystanders.  This arousal may be perceived as fear, disgust or sympathy, depending on aspects of the situation. 

Piliavin et al. go on to argue that the chosen response depends on a cost-reward analysis by the individual.  These include:

Costs of helping, such as effort, embarrassment and possible physical harm.
Cost of not helping, such as self-blame and perceived censure from others;
Rewards of helping, such as praise from self, onlookers and the victim;
Rewards of not helping, such as getting on with one’s own business and not incurring the possible costs of helping. 

Therefore according to this model we are motivated to help people not by altruism (acting in the interest of others) but as a way of reducing unpleasant feelings of arousal.


Attachment An emotional bond between an infant and its primary care giver. 
Bowlby developed the idea of monotropy: the idea that a human infant would develop only one special attachment to its mother, which was completely different from the other relationships which it developed, and that it would cause the child great distress and lasting damage if it was broken.   The Hodges and Tizard (1989) study questions this idea.


Attribution The process of giving reasons for why things happen or why people behave as they do.   See also dispositional attribution and situational attribution.


Attrition The loss of participants from a longitudinal study.  Reasons for attrition might include participants no longer wanting to take part in the study, moving away or losing contact.  When attrition occurs psychologists have to question the representativeness of the remaining sample.


Autism This syndrome is characterised by a triad of impairments.  (i) difficulties with social interaction, (ii) difficulties with verbal and non-verbal communication (iii) a lack of imaginative play.   Autistic children also often display a restricted range of activities and interests and obsessive tendencies.





Baron-Cohen et al. (1985)

The aim of Baron-Cohen's experiment was to demonstrate that the central deficit underlying autism is the autistic child's inability to employ a theory of mind.

Three groups of children were used a participants.  

20 autistic children with a mean chronological age (CA) of 11;11 (11 years, 11 months) and a mean verbal mental age (vMA) of 5;5;

14 Down's syndrome children with a mean CA of 10;11 and a mean vMA 2;11;

27 'normal' children with a CA of 4;5 (who were assumed to have vMA's equivalent to their CA).  

The 61 children were tested one at a time.  

The children were seated behind a desk opposite the experimenter.  

On the desk were two dolls, Sally and Anne.  Sally had a basket in front of her, and Anne had a box.  

The dolls were introduced to the children (e.g. ‘this is Sally’)

After introducing the dolls, the child's ability to name them was tested (the 'Naming Question').  

Sally then takes a marble and hides it in her basket.  She then leaves the room and 'goes for a walk'.  Whilst she is away, and therefore unknown to her, Anne takes the marble out of Sally's basket and puts it in her own box.  Sally returns and the child is asked the key question 'Where will Sally look for her marble?'  (the 'Belief Question').  The correct response is to point to or name Sally's basket; that is, to indicate that the child knows that Sally believes the marble to be somewhere where it is not.  The incorrect response is to point to Anne's box.

Two control questions are also asked:  'Where is the marble really?' ('Reality Question'), and 'Where was the marble in the beginning?' ('Memory Question').  

Every child was tested twice.  During the second time a new location (the experimenters pocket) for the marble was introduced:

For the children to succeed in this task they have to attribute a belief to Sally.  That is, the children have to be able to appreciate that Sally has beliefs about the world which can differ from their own beliefs, and which happen in this case not to be true.      

The percentage of correct responses to each of the four 'Sally-Anne' questions is shown in the table below.


Autistic children

Down's syndrome children

Normal children

Naming question




Reality question




Memory question




Belief question




The 'naming', 'reality', and 'memory' questions were answered correctly by all the children.  

However, whereas at least 85% of the 'normal' and Down's syndrome children gave the correct response to the belief question, only 20 % (4 from 20) of the autistic children were able to do so.

The 16 autistic children who gave the wrong response pointed to where the marble really was rather than to where Sally must believe it to be.

The findings support Baron-Cohen's argument that autistic children have under-developed 'theories of mind'.  According to Baron-Cohen, most of the autistic children were unable to appreciate that another person has their own beliefs which may not match up with how things really are. The results lend support to the notion that autistic children may have under-developed 'theories of mind'.


Behaviour An activity that can be directly observed and measured.  Unlike thoughts and feelings which cannot be directly observed and measured.  My spell checker spells it as 'behavior' as it is keeps setting its self to the US spell checker.


Behaviourism An approach in psychology which attempts to explain all behaviour in terms of learning.  This reductionist approach largely focuses on overt behaviour and ignores internal mechanisms such as cognitions (e.g. thoughts).
A page here where you can read more about behaviourism


Bobo doll An inflatable doll used in the Bandura core study.  A three and five foot doll were used. 


Brain Grey thing which weighs about 1.4kg (3lbs) and contains about 100 billion nerve cells (neurones).  There will be a good description of all of the important bits of the brain here soon.  Check out this brain flash movie


Brain scan Taking images of the living brain.  See PET scan.


Case study A detailed study of an individual or small group of people.  


Classical Conditioning

A form of learning through association.  Ivan Pavlov, whilst experimenting on dogs noticed that if a bell was rung at the same time as the dogs were fed, they would salivate merely at the sound of a bell.   This idea has been applied to humans to explain how certain behaviours are learned.  For example, it is argued that phobias can be explained using classical conditioning.  A person may have a phobia of horses because they once had a frightening experience with a horse and now they associate horses with this frightening experience.  Therefore another explanation for Hans' phobia of horses is that he was classically conditioned to fear horses.  Or in other words, Hans witnessed a horse fall and collapse in the street.  Hans then generalised this fear to all horses.

See also behaviourism

A game where you can be Pavlov.


Categorisation Grouping people into social categories or sets.  According to Tajfel (1970) categorisation is the minimum condition necessary to create discrimination. 


Cognition This refers to mental processes such as perception, memory, thinking and reasoning and so on.


Commisurotomy A surgical procedure to sever the corpus callosum.


Confounding variable A confounding variable is a variable which has an unintentional effect on the dependent variable.  When carrying out experiments we attempt to control extraneous variables, however there is always the possibility that one of these variables is not controlled and if this effects the dependent variable in a systematic way we call this a confounding variable.  


Conservation The ability to recognise that volume, number or mass do not change when the physical appearance changes.




This refers to the extent to which variables are held constant or regulated. See also extraneous variables, confounding variables and experimental designs.


Control group Often used in experiments.  This is a group which does not receive the manipulation of the independent variable and can be used for comparison with the experimental group or groups.


Corpus callosum The bundle of nerve fibres that connect the two hemispheres of the brain.


Correlation This refers to a measure of how strongly two or more variables are related to each other.

A positive correlation means that high values of one variable are associated with high values of the other. Or if you like, the variables increase together.

A negative correlation means that high values of one variable are associated with low values of the other. Or if you like, as one variable increases the other decreases. Note that like a positive correlation, a negative correlation still indicates that some kind of relationship exists.
If there is no correlation between two variables they are said to be uncorrelated.

Don't let yourself fall into the trap of believing that when there is a strong correlation between two variables that one of the variables causes the other. Association does not mean causation. For example, there is almost certainly a very high positive correlation between the length of people’s right arm and the length of their left arm. But the length of a persons left arm did not determine the length of their right arm. They are both determined by other factors i.e. genetics, diet etc.

A correlation coefficient refers to a number between -1 and +1 and states how strong a correlation is. If the number is close to +1 then there is a positive correlation. If the number is close to -1 then there is a negative correlation. If the number is close to 0 then the variables are uncorrelated.
Correlation coefficient can be calculated in a number of ways such as with a Spearman Rho.

Correlations are very good for showing possible relationships between variables and some times are the only practical or ethical way of carrying out an investigation. However, they cannot demonstrate a cause and effect.

Try this


Cortex The outer most layer of nerve tissue in the cerebral cortex.


Cross-cultural research  Research where more than one culture is studied.  Often cross-cultural research involves making comparisons between two cultures. 
A major advantage of cross-cultural studies is if we find differences between different cultural groups then, unless we have good reasons for believing that these differences are biologically caused, we are able to argue that these differences are due to environmental factors.

The major problem with cross-cultural studies is making sure that the measures are fair and appropriate for both cultures. (Cross-cultural studies are also, of course, expensive)


Cultural universal A cultural universal is a behaviour which is observed to be the same across cultures.  Deregowski used cross-cultural research to investigate if pictorial depth perception was a cultural universal.  His research suggests that pictorial depth perception is not a cultural universal. 




Decentre Jean Piaget argued that to decentre is to be able to take into account more than one aspect of a situation at a time.  According to Piaget, this type of thinking was typical of a child in the pre-operational stage.  The ability to conserve is an example of the ability to decentre.  


Defence mechanism A strategy used by the mind to defend itself from anxiety provoking thoughts.  In Freud's study of Little Hans he identified the defence mechanism known as identification with the aggressor.  Whereby Little Hans stresses all the ways that he is similar to his father, adopting his father's attitudes, mannerisms and actions, feeling that if his father sees him as similar, he will not feel hostile towards him.


Demand characteristics Any aspect of a study which has an influence on participants to do or answer what is expected of them. 


Depersonalisation A dissociative disorder where an individual loses their sense of identity.  See the studies by Zimbardo and Rosenhan.


Descriptive Statistics

Statistics are a method of summarising and analysing data for the purpose of drawing conclusions about the data.  

Carrying out psychological research often involves collecting a lot of data.   As psychologists therefore we need to have knowledge of statistics so that we can make conclusions about our data.

We can make a distinction between descriptive and inferential statistics.   Descriptive statistics simply offer us a way to describe a summary of our data. 

Inferential statistics go a step further and allow us to make a conclusion related to our hypothesis.

Descriptive statistics give us a way to summarise and describe our data but do not allow us to make a conclusion related to our hypothesis.

When carrying out a test of difference (activity C) there are two main ways of summarising the data using descriptive statistics.   The first way is to carry out of measure of central tendency (mean, median or mode) for each of the two conditions. 

The mean is calculated by adding all the scores together in each condition and then dividing by the number of scores.  This is a useful statistic as it takes all of the scores into account but can be misleading if there are extreme values.  For example if the scores on a memory test were 2, 4, 5, 6, 7, 42, the mean would be 10 which is not typical or representative of the data.

The median is calculated by finding the mid point in on ordered list.   The median is calculated by placing all the values of one condition in order and finding the mid- point.  This is a more useful measure than the mean when there are extreme values. 

The mode is the most common value in a set of values. 

The second way of summarising and describing data is to calculate a measure of dispersion.  This simply shows us the spread of a set of data.  A simple way of calculating the measure of dispersion is to calculate the range.  The range is the difference between the smallest and largest value in a set of scores.  Although it is a fairly crude measure of dispersion as any one high or low scale can distort the data.   A more sophisticated measure of dispersion is the standard deviation which tells us how much on average scores differ from the mean. 


When carrying out correlational analysis the data is summarised by presenting the data in a scattergram.   It is important that the scattergram has a title and both axes are labelled.   From the scattergram we may be able to say whether there is a strong positive correlation, a weak positive correlation, no correlation, a weak negative correlation or a strong negative correlation but we can not make a conclusion about the hypothesis.


Depth Cue A depth cue is something which gives us an indication of how far away an object or image is.  Pictorial depth cues include relative size and linear perspective.


Deregowski (1972)

The aim of Deregowski's study was to discover whether people in all cultures perceive pictures in the same way.  Or in Deregowski’s words do pictures offer a lingua franca for inter-cultural communication?

Deregowski conducted a review article which involved bringing together research by other psychologists and him-self.

Deregowski started his study by reviewing a number of reports of how people in different cultures often have difficulties with the perception of pictures (pictorial perception). For example, he recalled a story told by Mrs Donald Fraser, who taught health care to Africans in the 1920s. This is her description of an African woman slowly discovering that a picture she was looking at portrayed a human head in profile: 'She discovered in turn the nose, the mouth, the eye, but where was the other eye? I tried by turning my profile to explain why she could only see one eye but she hopped round to my other side to point out that I possessed a second eye which the other lacked'. Deregowski presented other anecdotal evidence to point out that some non-Western cultures find it difficult to perceive depth in pictures.

Deregowski then went on to describe experimental evidence which demonstrated the differences between cultural perception of pictures.

Non-Western participants were shown Hudson's test pictures which consisted of a series of pictures in which there were various combinations of three pictorial depth cues; relative size, superimposition and linear perspective.

Both children and adults from African tribes found it difficult to perceive depth in the pictorial material.

Research participants were shown a drawing of two squares, one behind the other and connected with a single rod. They were also given sticks and modelling clay and asked to build a model of what they saw.

Almost all the 3-D perceivers built a 3-D object. Participants who did not readily perceive depth in pictures tended to build a flat model.

Participants were asked to copy a 'two pronged trident’; a tantalising drawing that confuses many people. The confusion is apparently a direct result of attempting to interpret the drawing as a 3-D object. When asked to copy the ambiguous trident participants who were classified as 3-D perceivers spent more time looking at the ambiguous trident than at the control trident, whereas 2-D perceivers did not differ significantly in the time spent viewing each of the two tridents.

Or in other words the 2D perceivers could copy the trident quicker than the 3D perceivers.

Deregowski found that the 2-D perceivers prefer split type drawings to the perspective type. Split drawings are drawings that depict the essential characteristics of an object even if all those characteristics cannot be seen from a single view point - if you like, unfolded

Deregowski's major findings were that many non-Western tribal lack pictorial depth perception and that many non-Western tribal people prefer split drawings to perspective drawings.

Deregowski believes that non-Western people lack the ability to perceive and integrate depth cues in pictures. Deregowski believes this inability is due to some form of learning or lack of learning.

In accounting for the findings that some non-Western tribal people prefer split type drawings Deregowski believes that in all societies children have an aesthetic preference for drawings of the split type. In Western societies this preference is suppressed because the drawings do not convey information about the depicted objects as accurately as perspective drawings do. Therefore, according to Deregowski, we learn perspective drawings.


Determinism This is the argument that we do not have much control over our actions but are controlled by factors such as our biology or genes, or by the way we are brought up.  A consequence of this is that determinists believe that we are mainly passive responders to our past or biology and that we have no free will.

Determinists therefore believe that is possible to predict behaviour by identifying the cause of behaviour.

Although most psychologists believe in some form of determinism, many argue that hard determinism is too extreme.  They argue that humans do not always act involuntary and have some control over their behaviour.  This argument is known as soft determinism.

A further argument is that humans have free will.  The argument is that we have the freedom to act as we want at all times.  Psychologists who support the idea of free will, believe that the determinist argument is de-humanising as it treats people as if they were machines.

However, much of the research you will come across whilst studying psychology does not support the view that behaviour is unpredictable.  It is possible to identify behaviour patterns which, to some extent, do seem predictable. 


Diffusion of responsibility Diffusion of responsibility is the idea that people are less likely to intervene to help someone who seems to need it if there are others present, because they perceive responsibility as being shared between all present, and therefore see themselves as being less responsible personally.


Discrimination The behaviour that results from prejudice.


Dispositional attribution This is believing that a person's behaviour is caused by an individual's personality or disposition rather than the situation they are in.   See also situational attribution.


Down's syndrome A syndrome which is caused by having 47 chromosomes rather than 46 (23 pairs). 




Ecological Validity This term refers to how well a study can be related to or reflects everyday, real life.  Studies with high ecological validity can be generalised beyond the setting they were carried out in, whereas studies low in ecological validity cannot. (more on ecological validity)


Electroencephalogram (EEG) A method of recording activity in a living brain.  Electrodes are attached to a person's scalp to record general levels of electrical activity.


Epilepsy A neurological disorder which causes occasional storms of electrical activity in the brain.  This can lead to convulsions and loss of consciousness.
Link to the British Epilepsy Association web site.


Epinephrine See adrenaline.


Ethics These are a set of guidelines which psychologists carrying out research should follow.  (more on ethics)


Ethnocentric bias This is the tendency to perceive the world from your own cultural group, such as your ethnic group, national group and so on.  A consequence of this is that there can also be a tendency to view your own group as superior to other groups.


Ethnocentric sampling bias Most of the well known psychological research reported from before the 1980s was carried out in American universities using White, middle-class undergraduate students who are hardly representative of anybody other than American, White, middle-class undergraduate students.  Therefore we have to question the findings of studies which attempt to generalise their findings to the population as a whole.


Eugenics A political idea which argues that the human race should be improved by preventing 'undesirables' from breeding so they cannot pass on their supposedly inferior genes.  This argument has culminated in compulsory sterilisation, mass murder and genocide.


Experiment A research method used by psychologists which involves the manipulation of variables in order to discover cause and effect.  It differs from non-experimental methods in that it involves the deliberate manipulation of one variable, while trying to keep all other variables constant.

There are three main types of experiment - laboratory experiments, field experiments and quasi (natural) experiments.

Try these


Experimental Designs There are three basic experimental designsindependent measures design, repeated measures design and matched pairs design.

An experimental design is a set of procedures used to control the influence of participant variables so that we can investigate the possible effects of the independent variable on the dependent variable.


Experimenter A person doing an experiment.  This might just be my problem but I do get annoyed when students write 'the experimenters did a case study'.   I think experimenters carry out experimenters.  Why not write 'the researchers did a case study'?  Go on - just for me.


Extraneous variable An extraneous variable is a variable which could effect the dependent variable but which is controlled so that it does not become a confounding variable


Eye witness testimony Descriptions of events given by observers of an event.  These are generally used in criminal cases whereby individuals have to give an account of a crime to the police or a court.  Elizabeth Loftus has demonstrated that memory is reconstructive and that eye witness testimonies are unreliable.



Field Experiment An experiment which is carried out in ‘the field ’.  That is, in a real world situation.  In field experiments the participants are not usually aware that that they are participating in an experiment.

The independent variable is still manipulated unlike in natural experiments.  Field experiments are usually high in ecological validity and may avoid demand characteristics as the participants are unaware of the experiment.  However in field experiments it is much harder to control confounding variables and they are usually more time consuming and expensive.  

In field experiments it is not possible to gain informed consent from the participants and it is  difficult to debrief the participants.



Gardner and Gardner (1969)

The aim of the study was to demonstrate that a chimpanzee does has the capability to use human language.

The Gardners decided they wanted as young a chimp as was possible in case there was a critical early stage at which such behaviour had to be acquired.  Because newborn laboratory chimps are very scarce it was decided to obtain a wild caught infant.

When Washoe arrived at the laboratory in June 1966 she was estimated to be between 8 and 14 months. 

The Gardners ensured that Washoe had lots of human companions who all had to master American Sign Language (ASL).  The environment was designed to provide maximum stimulation with as few restrictions as possible.

The Gardners decided to use ASL because chimpanzees could not all the correct sounds necessary for spoken language and because chimpanzees make use of gestures naturally. 

Washoe was taught mainly using imitation and operant conditioning.  Operant conditioning is simply reinforcing behaviour which is desired.  The Gardners found that Washoe would learn some signs by observing and imitating, but often had to "mould" her hands into the right shapes when they were teaching her new signs.  Behaviour was rewarded by praising her and tickling.

Records were kept about the amount of signing behaviour and number of signs used.

A sign was recorded if it was reported by three different observers, as having occurred in an appropriate context and spontaneously (i.e. with no prompting other than a question such as "what is it?" or "what do you want?").  A reported frequency of at least one appropriate and spontaneous occurrence each day over a period of 15 consecutive days was taken as the criterion of acquisition.  

By the end of 22 months of the programme at least 30 signs met this strict criterion.  Washoe was also demonstrating displacement - that is referring to things that were not present.  She could also spontaneously combine two signs e.g. "gimme tickle".

The Gardners believed that they were able to verify their hypothesis that sign language is an appropriate medium of two-way communication for the chimp.  The Gardners at this point of the study (32 months of the programme) believed that Washoe would develop even further in her attempts at sign language and that her achievements would probably be exceeded by another chimp.


Gender Your sense of being either male of female. 


Gene A unit of inheritance which forms part of a chromosome.


Generalisation The extent to which results from one sample of participants can be applied to wider groups.  The generalisability of the results of a study is partly dependent on the success of the sampling technique (e.g. was the sample representative of the population) and the representativeness of the population chosen (for example if the sample was taken from students then it is not reasonable to generalise the results to all types of people).



Hull City Promoted to the Championship.  Which way is the Premiership?  Unique in that it is the only club in the football league whose letters can't be coloured in.


Hypnosis A trance like state which is induced by a hypnotist.  It may involve heightened suggestibility and attention on the hypnotist.  Some psychologists argue that hypnosis is a matter of suggestible people role-playing a trance state and other psychologists argue that it is an altered state of consciousness as demonstrated by different brain activity from EEG records. 

Hull City supporters would argue that the same trance like affect can be gained by visiting the KC stadium.


Hypotheses Plural of hypothesis


Hypothesis A testable, predictive statement.   This statement is tested by researchers to see if it is true.   The hypothesis either states a predicted difference between an independent and dependent variable (an experimental hypothesis), or it states a predicted relationship between variables (in the case of a correlational analysis). See also null hypothesis


Identification with the aggressor See defence mechanism.


Independent Measures Design An independent measures design is a type of experimental design.

An experimental design is a set of procedures used to control the influence of participant variables so that we can investigate the possible effects of the independent variable on the dependent variable.

An independent measures design consists of using different participants for each condition of the experiment.  If two groups in an experiment consist of different individuals then this is an independent measures design. 

This type of design has an advantage resulting from the different participants used in each condition - there is no problem with order effects

The most serious disadvantage of independent measures designs is the potential for error resulting from individual differences between the groups of participants taking part in the different conditions.  Also an independent groups design may represent an uneconomic use of those participants, since twice as many participants are needed to obtain the same amount of data as would be required in a two-condition repeated measures design.


Imitation Copying somebody else's behaviour such as aggression in the Bandura experiment and signs in Gardner and Gardner's case study.   See also Social learning Theory.


Individual and situational explanations These arguments refer to where we look for the cause of behaviour.  Some of the core studies look for the explanation of behaviour being within the individual.  For example, behaviour could be described as resulting from the individual's personality or dispositions.  

Other core studies look for the explanation of behaviour as a result of the situation a person is in.  For example, behaviour could be described as resulting from group pressure, the environment and so on.


Inferential Statistics

Statistics are a method of summarising and analysing data for the purpose of drawing conclusions about the data.  

Carrying out psychological research often involves collecting a lot of data.   As psychologists therefore we need to have knowledge of statistics so that we can make conclusions about our data.

We can make a distinction between descriptive and inferential statistics.   Descriptive statistics simply offer us a way to describe a summary of our data. 

Inferential statistics go a step further and allow us to make a conclusion related to our hypothesis.

As the name suggests inferential statistics attempt to make an inference about our data.  That is, which hypothesis offers the best explanation for our results?

When we carry out a test of difference (activity C) we have two hypotheses.  A null hypothesis which states that the results will be due to chance, and the experimental (alternate) hypothesis, which predicts that the results are due to the manipulation of the independent variable. 

To assess the probability that the results are due to chance an inferential statistical test is used.   Inferential statistics tell us whether the difference between two sets of scores is significant or due to chance.  It is an academic convention that in psychology we accept the null hypothesis as the best explanation for out results unless there is a 5% probability (or less) of the results being due to chance.

5% probability is expressed as p<0.05 and if we find that the null hypothesis can be rejected we can be 95% confident of the conclusions.

When carrying out a test of difference (activity C) if the design is an independent measures design the appropriate inferential statistical test to use is the Mann Whitney U test.  

 When carrying out a test of difference (activity C) if the design is a repeated measures design the appropriate inferential statistical test to use is the Wilcoxon signed ranks test.  

To use this as a spread sheet go to

Whichever test is used a value is calculated which is called the observed value.  The value then has to be compared with the critical value to determine whether the null hypothesis can be rejected and at what value

When we carry out a test of correlation we have two hypotheses.  A null hypothesis which states that the results will be due to chance, and the correlational hypothesis, which predicts that there is a correlation or relationship between the two variables 

To assess the probability that the results are due to chance an inferential statistical test is used.   Inferential statistics tell us whether the relationship between two sets of scores is significant or due to chance.  It is an academic convention that in psychology we accept the null hypothesis as the best explanation for out results unless there is a 5% probability (or less) of the results being due to chance.

5% probability is expressed as p<0.05 and if we find that the null hypothesis can be rejected it we can be 95% confident of the conclusions.


When carrying out a test of correlation a Spearman Rho is used.  

Using a Spearman’s Rho a value is calculated which is called the observed value.  The value then has to be compared with the critical value to determine whether the null hypothesis can be rejected and at what value.



A group to which a person belongs, or thinks he or she belongs.


Intelligence Quotient (IQ) This is a measure of intelligence.  An IQ test produces a score which represents a persons mental age (MA).  This is usually divided by the persons chronological age (CA) because children of the same intelligence but different ages will not achieve the same score on the test.  The quotient is divided by 100 to remove any fractions.

The average IQ is 100 and the scores are standardised so that about 64% of the population have a score between 85 and 115. 


Inter-rater reliability This is the extent to which two raters provide consistent or similar responses.  The ratings for each observer  are correlated to check for agreement.  It is a method of assessing the reliability of a set of measurements or ratings such as in an observation. 



Jigsaw Technique Work by psychologists such as Tajfel has stimulated work into reducing prejudice. Aronson et al. (1978) developed the jigsaw classroom technique whereby all the children have to cooperate with others in order to complete tasks.  This technique even has its own web site.




Laboratory Any environment where variables can be well controlled.  Such environments are usually artificial but do not have to resemble a science lab at school. 


Laboratory experiment An experiment which is conducted under highly controlled conditions.

The variable which is being manipulated by the researcher is called the independent variable and the dependent variable is the change in behaviour measured by the researcher.

All other variables which might affect the results and therefore give us a false set of results are called confounding variables (also referred to as random variables).

By changing one variable (the IV) while measuring another (the DV) while we control all others, as far as possible, then the experimental method allows us to draw conclusions with far more certainty than any non-experimental method. If the IV is the only thing that is changed then it must be responsible for any change in the dependent variable.

Laboratory experiments allow for precise control of variables. The purpose of control is to enable the experimenter to isolate the one key variable which has been selected (the IV), in order to observe its effect on some other variable (the DV); control is intended to allow us to conclude that it is the IV, and nothing else, which is influencing the DV.

However it must also be noted that it is not possible to completely control all variables. There may be other variables at work which the experimenter is unaware of.

It is argued that laboratory experiments allow us to make statements about cause and effect, because unlike non-experimental methods they involve the deliberate manipulation of one variable, while trying to keep all other variables constant. Sometimes the independent variable (IV) is thought of as the cause and the dependent variable (DV) as the effect.

Furthermore experiments can be replicated. The experimental method consists of standardised procedures and measures which allow it to be easily repeated.

However such experiments are not typical of real life situations. These types of experiments are conducted in laboratories - strange and contrived environments in which people are asked to perform unusual or even bizarre tasks. The artificiality of the lab, together with the 'unnatural' things that the subjects may be asked to do, jointly produces a distortion of behaviour. Therefore it should be difficult to generalise findings from experiments because they are not ecologically valid (true to real life).

A further difficulty with the experimental method is demand characteristics. Demand characteristics are all the cues which convey to the participant the purpose of the experiment. A psychology experiment is a social situation in which neither the participants or the experimenters are passive, inanimate objects but are active, thinking human beings.

Another major problem with the experimental method concerns ethics. For example, experiments nearly always involve deceiving participants to some extent and it is important to recognise that there are very many areas of human life which cannot be studied using the experimental method because it would be simply too unethical to do so.


Lateralisation of brain function This refers to the uneven distribution of tasks carried out by the hemispheres.  Lateral means side.  Any function, e.g. language, which is found on one side of the brain is called a lateralised function.


Leading question A question that suggests what answer is desired or leads to the desired answer.


Likert Scale A type of closed question which is often used a way of measuring attitudes.  Respondents are asked to state on a scale (usually it is 1 -5 or 1 -7) how strongly they agree with a statement.  For example 1 could be strongly disagree and 5 could be strongly agree.  Named after its inventor Rensis Likert.  


Loftus and Palmer (1974)

The aim of Loftus and Palmer’s experiments was to investigate how information supplied after an event, influences a witness's memory for that event.

First Experiment

The participants in the first experiment were 45 students of the University of Washington. 

They were each shown seven film-clips of traffic accidents.  Following each clip, the students were asked to write an account of the accident they had just seen.  They were also asked to answer some specific questions but the critical question was to do with the speed of the vehicles involved in the collision.

There were five conditions in the experiment (each with nine participants) and the independent variable was manipulated by means of the wording of the questions.

The critical question was ‘About how fast were the cars going when they ***** each other?'.  In each condition, a different word or phrase was used to fill in the blank.  These words were; smashed, collided, bumped, hit, contacted.

The dependent variable was the speed estimates given by the participants.

Speed estimates for the verbs used in the estimation of speed question














The results demonstrated that the phrasing of the question brought about a change in speed estimate.  With smashed eliciting a higher speed estimate than contacted.


Second Experiment

A similar procedure was used whereby 150 student participants viewed a short (one minute) film which contained a 4 second scene of a multiple car accident, and were then questioned about it.

There were three conditions and the independent variable was manipulated by the wording of the question.

50 of the participants were asked 'How fast were the cars going when they hit each other?’

50 of the participants were asked 'How fast were the cars going when they smashed into each other?'

50 of the participants were not interrogated about the speed of the vehicles.

One week later, the participants returned and, without viewing the film again, they answered a series of questions about the accident.  The critical question was 'Did you see any broken glass?'  The critical question was part of a longer series of questions and was placed in a random position on each participants question paper.  There was in fact no broken glass in the film.

Response to the question 'Did you see any broken glass?'













These results show a significant effect of the verb in the question on the mis-perception of glass in the film.  Those participants that heard the word smashed were more than twice as likely to recall seeing broken glass.

Loftus and Palmer gave two interpretations/explanations for the findings of their 1st experiment.

1.   Firstly, they argued that the results could be due to a distortion in the memory of the participant.  The memory of how fast the cars were travelling could have been distorted by the verbal label which had been used to characterise the intensity of the crash. 

2.   Secondly, they argue that the results could be due to response-bias factors, in which case the participant is not sure of the exact speed and therefore adjusts his or her estimate to fit in with the expectations of the questioner.  (This is also an example of a demand characteristic)

The second experiment though offers more support for the second explanation.

To account for the results of the second experiment, Loftus and Palmer developed the following explanation called the reconstructive hypothesis:

They argue that two kinds of information go into a person's memory of an event.  The first is the information obtained from perceiving an event (e.g. witnessing a video of a car accident), and the second is the other information supplied to us after the event (e.g. the question containing hit or smashed).  Over time, the information from these two sources may be integrated in such a way that we are unable to tell from which source some specific detail is recalled.  All we have is one 'memory'. 

For example in Loftus and Palmer's 2nd experiment, the participants first form some memory of the video they have witnessed.  The experimenter then, while asking, "About how fast were the cars going when they smashed into each other?" supplies a piece of external information, namely, that the cars did indeed smash into each other.  When these two pieces of information are integrated, the participant has a memory of an accident that was more severe than in fact it was.   Since broken glass corresponds to a severe accident, the participant is more likely to think that broken glass was present.


Longitudinal approach A longitudinal approach is where a group of participants are followed up after a period of time.  Longitudinal studies are usually found in the area of developmental psychology because they are ways of studying change over time. It is important to recognise that longitudinal studies represent an approach and not an actual method of collecting data.



Mann-Whitney U test A really fun inferential statistical test of the the difference between two independent groups, which you may come across for your psychological investigations paper.


Matched pairs design


A matched pairs design is a type of experimental design.

An experimental design is a set of procedures used to control the influence of participant variables so that we can investigate the possible effects of the independent variable on the dependent variable.

A matched pairs design consists of using different participants for each condition of the experiment but participant variables are controlled by matching pairs of variables on a key variable. 

In order to get the pairing precise enough, it is common to get one group of participants together and then look round for partners for everyone.  Participants can be matched on variables which are considered to be relevant to the experiment in question.  For example, pairs of participants might be matched for their scores from intelligence or personality tests.

Although this design combines the key benefits of both an independent and repeated measures design, achieving matched pairs of participants is a difficult and time consuming task which may be too costly to undertake.  Successful use of a matched pairs design is heavily dependent on the use of reliable and valid procedures for pre-testing participants to obtain matched the pairs.


Maturation This is a term used to describe development which occurs as a result of genes, but which emerges as we grow older.  Puberty is a good example of this.  Jean Piaget believed that cognitive development was also maturational in that a child is only able to complete certain tasks until the individual is biologically ready.


Memory The capacity to retain and store information.


Milgram (1963)

The aim of Milgram’s (1963) experiment was to investigate what level of obedience would be shown when participants were told by an authority figure to administer electric shocks to another person.

The participants consisted of 40 males aged between 20 and 50 years of age who were recruited by a newspaper and direct mail advertisement which asked for volunteers to participate in a study of memory and learning at Yale University. 

Each participant turned up to the laboratory alone and was asked to draw a slip of paper from a hat to determine which role he would play.  The draw was rigged so the participant was always the teacher and Mr. Wallace (the confederate) was always the learner.

The teacher (participant) and learner were taken to a room and in full view of the teacher (participant) the learner was strapped into the ‘electric chair’.  The experimenter explained to the teacher (participant) that the straps were to prevent excessive movement while the learner was being shocked; the effect was to make it impossible for him to escape the situation.  An electrode was attached to the learner’s wrist and electrode paste (cream) was applied ‘to avoid blisters and burns’.  The participant (teacher) was told that the electrode was attached to the shock generator in the adjoining room.  The participant (teacher) then heard the experimenter tell the learner ‘although the shocks can be extremely painful, they cause no permanent tissue damage’.  

Milgram created a phoney ‘shock generator’ which in the 1960s looked very impressive and realistic.  The phoney shock generator had 30 switches marked clearly in 15 volt increments from 15 to 450 volts.  

The participant (teacher) was then seated in an adjacent room in front of the shock generator and asked to read a series of word pairs to the learner.  The learner was asked to learn (memorise) these pairs.  The participant (teacher) then tested the learner by giving him one of the words in a pair along with four other words.  The learner had to indicate which of the four words had originally been paired with the first word.  The learner’s answer was communicated by pressing one of four switches which illuminated a light on top of the shock generator.  If the answer was correct the participant (teacher) had to move onto the next word on the list, if the answer was wrong the participant had to tell the learner the correct answer and then the level of punishment that they were going to give them.  They would then press the first switch on the shock generator (15 volts).  For every subsequent incorrect answer the participant was required to move one switch up the scale of shocks (15 volts higher than the voltage of the last shock delivered).

If the participant asked advice from the experimenter, whether it be; ‘should I continue administering shocks’, or some other indication that he did not wish to go on, he would be given encouragement to continue with a sequence of standardised ‘prods’ such as “Please continue” or “The experiment requires that you continue”

All 40 of the participants obeyed the experimenter and delivered shocks up to 300 volts.  26 of the 40 participants delivered shocks up to the maximum 450 volts. 

After the maximum shock had been administered, the participant was asked to continue at this level until the experimenter eventually called a halt to the proceedings, at which point many of the obedient participants heaved sighs of relief or shook their heads in apparent regret.

During the study many participants showed signs of nervousness and tension. Participants sweated, trembled, stuttered, bit their lips, groaned, dug fingernails into their flesh, and these were typical not exceptional responses.  Quite a common sign of tension was nervous laughing fits (14 out of 40 participants), which seemed entirely out of place, even bizarre.  Full-blown uncontrollable seizures were observed for three participants

Milgram put forward a number of possible explanations for this high level of obedience.  Including the fact that the experiment took place at the prestigious Yale University, that the participant believed that the experiment was for a worthy purpose and that the participant believed the victim had volunteered to be in the study and therefore has an obligation to take part even if the procedures become unpleasant.


Minimal groups This term has been used to describe studies like those of Tajfel's whereby artificial groups are created on the basis of almost meaningless (hence minimal) categories (e.g. under and over estimators) and then studying the effects which result.


Monotropy See attachment


Multiple Personality Disorder Multiple Personality Disorder (MPD) is a dissociative disorder in which two or more distinct personalities coexist within  the same individual.  MPD is nowadays referred to as Dissociative Identity Disorder.



Native intellectual ability Yerkes argued that his intelligence tests measured native intellectual ability, that is, innate intelligence which was unaffected by culture and educational opportunities.   Gould demonstrated that the tests actually measured cultural and educational background.


Natural experiment See quasi experiment


Nature-nurture debate This is a long running debate which is interested in whether we are like the way we are because of nature (inherited and genetic) or nurture (experiences and influences after conception).  (more on nature-nurture)


Non-participant observation A type of observational study whereby the researcher does not join in with the activity being observed. 


Null Hypothesis The statement of either no difference between the independent and dependent variable in the case of an experimental hypothesis, or no relationship between the independent variables in the case of a correlational analysis.


Obedience Following out the order of others.  Usually the orders of those in authority. 


Obligation effect This is a problem often found with questionnaires.  When participants are asked to answer a large number of questions they often feel obliged to fill in the questionnaire even if they may not have any views on the topic being asked.  This often happens in psychology coursework.


Observational learning Observational learning is learning through imitation.  See also Social Learning Theory.


Observation All types of research involve some element of observation.  It is not just observational studies that use observation.  For example, when we use self report measures we observe the responses of the participants, when we carry out experiments we observe the behaviour of our participants and so on.


Observational study Observation studies are those where the researcher observes a situation and records what happens but does not manipulate an independent variable.  

Observational studies therefore tend to be high in ecological validity as there is no intervention and if the observer remains undetected the method avoids problems with experimenter effects.  

On the other hand observational studies are difficult to replicate. 

There are a number of different types of observational studies including non-participant and participant observations, undisclosed observations and structured and unstructured observations.

Oedipus complex Freud thought that, during the phallic stage, the young boy develops an intense sexual love for his mother. and because of this, he sees his father as a rival, and wants to get rid of him.

 The father, however, is far bigger and more powerful than the young boy, and so the child develops a fear that, seeing him as a rival, his father will castrate him.

Because it is impossible to live with the continual castration-threat anxiety provided by this conflict, the young boy develops a mechanism for coping with it, using a defence mechanism known as 'identification with the aggressor'. 

He stresses all the ways that he is similar to his father, adopting his father's attitudes, mannerisms and actions, feeling that if his father sees him as similar, he will not feel hostile towards him.


Operant conditioning A form of learning due to the consequences of behaviour, through reinforcement and punishment.  Operant conditioning was used in the Gardner and Gardner study as the researchers rewarded Washoe's signing with praises and tickles.
Opportunity sampling

Opportunity sampling is the sampling technique most used by psychology students.  It consists of taking the sample from people who are available at the time the study is carried out and fit the criteria your are looking for. 

This may simple consist of choosing the first 20 students  in your college canteen to fill in your questionnaire.

It is a popular sampling technique as it is easy in terms of time and therefore money.  For example the researcher may use friends, family or colleagues.  It can also be seen as adequate when investigating processes which are thought to work in similar ways for most individuals such as memory processes.   Sometimes, particularly with natural experiments opportunity sampling has to be used as the researcher has no control over who is studied.

However, there are many weaknesses of opportunity sampling.  Opportunity sampling can produce a biased sample as it is easy for the researcher to choose people from their own social and cultural group.  This sample would therefore not be representative of your target population as you friends may have different qualities to people in general. 

A further problem with opportunity sampling is that participants may decline to take part and your sampling technique may turn into a self selected sample.


Participant observation A type of observational study where the observer is also a participant in the activity being studied.


Pathology of power In the Zimbardo study this was the oppressive behaviour often displayed by the guards when they seemed to enjoy and abuse the extreme control and power they had over the prisoners.


Pathological prisoner syndrome This term was used by Zimbardo to explain the social deterioration of the prisoners.  At the beginning of the study, the prisoners rebelled against their conditions but eventually became passive, dependent and had flattened emotions.


Perception The way way we analyse and make sense of the information we receive from our senses.  Absolutely amazing.


Personality An individuals distinctive and relatively stable pattern of thoughts, behaviours and emotions.


Perspective drawings Perspective drawings are those which give just one perspective of an object, with features that cannot be viewed from that perspective not represented in the picture.  Perspective drawings often include pictorial depth cues which give an illusion of depth.


PET scan PET stands for Positron Emission Tomography.  PET scans can be used to examine the relationship between the metabolic activity in the brain and mental processes.  

A small amount of harmless radioactive material is injected into the participant which bonds to a substance such as glucose.   This is called a tracer.  As the brain uses glucose as energy, the areas of the brain which are most active absorb it.  The glucose is broken down but the radioactive material remains and it emits positively charged particles called positrons which are picked up by the scan.  This information can be read by a computer which produces coloured images of the level of activity occurring throughout the brain.   PET scanning is the most established of brain-imaging techniques, but requires massive investment.


Phallic stage Freud argued that during the phallic stage (from three to five years old) a child would focus its sexual energy on its genitals.  This was when a child's sexual identification was established.   During this stage Freud argued that a young boy would experience what he called the Oedipus complex.  This would provide the child with highly disturbing conflicts, which had to be resolved by the child identifying with the same-sexed parent.


Phallus A penis.  Things that are perceived to resemble a penis are said to be phallic symbols. 


Phobia An irrational fear that interferes with day-to-day life.


Physiological Relating to the functioning of the nervous system including the brain.


Piliavin et al.(1969)

The aim of this study was to investigate the effect of

the type of victim (drunk or ill) which gained most help

the race of the victim (black or white) which gained most help

the speed of helping, frequency of helping and the race of the helper. 

The study also sought to study the impact of the presence of a model (someone who offers help first) in emergency situations, as well as to examine the relationship between the size of the group and frequency of helping.

The participants were approximately 4450 men and women travelling on a particular stretch of the New York underground system between 11 a.m. and 3 p.m. on weekdays during April and June 1968.  The average racial composition of the passengers on the train, which travelled through Harlem to the Bronx, was 45% black and 55% white.  The average number of people in the train carriage was 43, and the average number of people in the critical area where the incident was staged was 8.5.

Two particular trains were selected for the study because they did not make any stops for about 7.5 minutes there was a captive audience who, after the first 70 seconds of their journey became bystanders to an emergency.  A single trial was a non-stop, 7.5-minute journey in either direction. 

On each trial, a team of four Columbia General Studies students, two males and two females, boarded the train using different doors.  Four dif­ferent teams, whose members always worked together, collected data for 103 trials.  The female confederates sat outside the critical area and recorded data as unobtrusively as possible during the journey, while the male model and victim remained standing.  The victim always stood next to a pole in the centre of the critical area.  As the train passed the first station (approximately 70 seconds after depart­ing), the victim staggered forward and collapsed  If he received no help by the time the train slowed to a stop, the model helped him to his feet.  At the stop, the team got off and waited separately until other pas­sengers had left the station before proceeding to another platform to board a train going in the opposite direction for the next trial.  Six to eight trials were run on any given day and all trials on a given day were in the same ‘victim condition’.

The four victims (one from each team) were males, aged between 26 and 35, three white, one black, all identically dressed.  On 38 trials the victims smelled of alcohol and car­ried a bottle wrapped tightly in a brown bag (drunk condition),

On the remaining 65 trials they appeared sober and carried a black cane (cane condition). 

Four white males (aged 24 to 29) played the role of model in each team.

There were four different model conditions used across both drunk and cane victim conditions:

·         Critical area - early:  model stood in critical area and waited until passing the fourth station before assisting the victim (approximately 70 seconds after the collapse).

·         Critical area - late:  model stood in critical area and waited until passing the sixth station before assisting the victim (approximately 150 seconds after the collapse).

·         Adjacent area - early:  model stood in middle of the compartment, adjacent to critical area and waited until passing the fourth station.

·         Adjacent area - late:  model stood in adjacent area and waited until passing the sixth station.

On each trial one observer noted the race, sex and location of every pas­senger, seated or standing, in the critical area, together with the total number of passengers and the total number who came to the victim’s assistance, plus their race, sex and location.  A second observer in the adjacent area did the same and both observers recorded comments spontaneously made by nearby passengers and also tried to elicit comments from a passenger sitting next to them.

The results showed that helping was very high.

The cane victim received spontaneous help on 62 out of the 65 trials, and the drunk victim received spontaneous help on 19 out of 38 trials. 

On 60% of the 81 trials where spontaneous help was given, more than one person offered help. 

Once one person had started to help, there were no differences for different victim conditions (black/white, cane/drunk) on the number of extra helpers that appeared. 

The race of the victims made no significant difference to helping behaviour, but there was a slight tendency for same-race helping in the drunken condition.

90% of helpers were male.  Although there were more men present, this percentage was statistically significant;

64% of the helpers were white; this was what would be expected based on the racial distribution of the carriage.

On the majority of the trials, the model did not get the opportunity to act, so no extensive analysis was made of the effect of the model.



The population is the group of people from whom the sample is drawn.  For example if the sample of participants is taken from sixth form colleges in Hull, the findings of the study can only be applied to that group of people and not all sixth form students in the UK and certainly not all people in the world.

Obviously it is not usually possible to test everyone in the target population so therefore psychologists use sampling techniques to choose people who are representative (typical) of the population as a whole.


Powerlessness A sense of having little control over what happens to you.  As demonstrated in the study by Rosenthal.


Prejudice An attitude (usually negative) toward the member of some group solely on their membership in that group.  Literally 'pre-judgement'.


Projective tests Tests which involve asking respondents to interpret a picture.  It is thought that such tests reveal aspects of the unconscious mind.  An example of a projective test is the Rorschach test used by Thigpen and Cleckley.


Pseudo-patient In the Rosenhan study this refers to a researcher who is pretending to be a patient.


Psychiatrist A person who is medically qualified and then specialises in treating psychological disorders.


Psychoanalysis Theories developed from Freud's explanations about personality and how behaviour is influenced by unconscious thoughts and feelings.
Click here for more on psychoanalysis.  


Psychology What you are studying.   The systematic study of experience and behaviour.


Psychometrics These are instruments or test developed for measuring mental characteristics.  These psychometric tests have been designed to measure a wide range of mental characteristics, including personality, intelligence, mental health, brain damage and so on.  (more on psychometrics)



Qualitative data Data that describes meaning and experiences are known as qualitative data. (more on quantitative and qualitative data)


Quantitative data Data that focuses on numbers and frequencies are known as quantitative data.  (more on quantitative and qualitative data)


Quasi experiment An experiment where the independent variable is not manipulated by the experimenter but occurs naturally.  These experiments are often called natural experiments.

In some circumstances, psychologists can take advantage of a natural situation in order to carry out an investigation in circumstances which they cannot themselves manipulate.  For example, an all boy’s schools grades may be compared with a mixed schools grades.  The effects on the participants of being in single sex or mixed sex schools could be compared.

This is not a true experiment because the psychologist is unable to manipulate or control all variables.  For this reason it is referred to as a quasi-experiment.  It is possible, though to compare two groups, the equivalent of an experimental and a control group.  It has the advantage that the participants are unaware that they are taking part in an investigation and it is certainly not as artificial as a laboratory setting.



Questionnaires Questionnaires are a type of self report method which consist of a set of questions usually in a highly structured written form.


Random sampling

This is a sampling technique which is defined as a sample in which every member of the population has an equal chance of being chosen.  This involves identifying everyone in the target population and then selecting the number of participants you need in a way that gives everyone in the population an equal chance of being picked.  For example, you could put all of the names of the students at your college in a hat and pick out however many you need.  

Random sampling is the best technique for providing an unbiased representative sample of a target population.

However random sampling does have limitations.  Random sampling can be very time consuming and is often impossible to carry out, particularly when you have a large target population, of say all students.  For example if you do not have the names of all the people in your target population you would struggle to conduct a random sample.   If you ask people to volunteer for a study the sample is already not random as some people may be more or less likely to volunteer for things.   Similarly if you decided to put out an advert for participants it would be almost impossible to guarantee that every member of your target population has an equal chance of viewing the advert.


Reconstructive memory hypothesis This is the argument that two kinds of information go into a person's memory of an event.  The first is the information obtained from perceiving an event, and the second is the other information supplied to us after the event.  Over time, the information from these two sources may be integrated in such a way that we are unable to tell from which source some specific detail is recalled.  All we have is one 'memory'. 


Reductionism Reductionism is the argument that we can explain behaviour and experiences by reference to only one factor, such as physiology or learning.

There are many different types of reductionism.

 Physiological reductionism, for example, argues that all behaviour and experiences can be explained (or reduced to) by biological factors such as hormones or the nervous system

Whereas genetic reductionism reduces all causes of behaviour to genetic inheritance. 

Social reductionism argues that all behaviour and experiences can be explained simply by the affect of groups on the individual.

The criticism of reductionist arguments is that they are too simplistic because they ignore the complexities of human behaviour and experience.  Behaviour often has a number of different causes and to reduce the possible explanations to one level can only provide a limited understanding.  

However, an advantage of the reductionist views is that by breaking down a phenomena to its constituent parts it may be possible to understand the whole.   This type of single mindedness has lead to some great discoveries in psychology as it has in the 'natural' sciences.


Regression Returning to an earlier, usually childlike, state.  Believed by many psychologists to be a way of coping with anxieties.



It might look like this if
a person had their eyes


Rapid eye movements which occur during the stage of sleep when it is thought we are dreaming.  During this stage the body is in a state of paralysis.


Repeated Measures Design

A repeated measures design is a type of experimental design.

An experimental design is a set of procedures used to control the influence of participant variables so that we can investigate the possible effects of the independent variable on the dependent variable.

A repeated measures design consists of testing the same individuals on two or more conditions.

The key advantage of the repeated measures design is that individual differences between participants are removed as a potential confounding variable. Also the repeated measures design requires fewer participants, since data for all conditions derive from the same group of participants.

The design also has its disadvantages.  The range of potential uses is smaller than for the independent groups design.  For example, it is not always possible to test the same participants twice.  

There is also a potential disadvantage resulting from order effects, although these order effects can be minimised.  Order effects occur when people behave differently because of the order in which the conditions are performed.  For example, the participant’s performance may be enhanced because of a practice effect, or performance may be reduced because of a boredom or fatigue effect.

Order effects act as a confounding variable but can be reduced by using counterbalancing.  If there are two conditions in an experiment the first participant can do the first condition first and the second condition second.  The second participant can do the second condition first and the first condition second and so on.  Therefore any order effects should be randomised.


Repression When an individual keeps anxiety proving thoughts out of their conscious awareness possibly as of way of coping.


Reinforcement A reinforcement is anything which will increase the probability that a behaviour or action will be repeated again in a similar circumstance.  That is, if we receive something we perceive as rewarding (e.g. a smile) after we have performed a particular action (e.g. told a joke) we will be more likely to carry out that behaviour again.  If we do not receive a reinforcement we will be less likely to perform that behaviour again.  (see also operant conditioning)


Reliability This refers to how consistent a measuring device is.  A measurement is said to be reliable or consistent if the measurement can produce similar results if used again in similar circumstances.  For example, if a speedometer gave the same readings at the same speed it would be reliable.  If it didn't it would be pretty useless and unreliable (more on reliability).


Review article A report which either brings together other researchers evidence (e.g. Deregowski 1972) or evaluates the research carried out by another psychologist (e.g. Gould 1982).


Rorschach test

A type of projective test which consists of asking respondents what they see in symmetrical inkblot pictures.  It is thought that such tests reveal aspects of the unconscious mind.  

More detailed description and evaluation here.



Sally-Anne test The procedure used by Baron-Cohen to test for theory of mind.  The procedure is designed to find out if a child can recognise that a doll has a false belief about the whereabouts of a marble because she did not see it being moved from its original place.

Cute picture here


Sampling technique A method used to choose a sample of a population.  Examples include, random sampling, opportunity sampling, stratified sampling, snow ball sampling and self selected sampling.


Schizophrenia A mental disorder where contact with reality and insight are impaired.  Other symptoms can include hallucinations and  delusions.  


Schizophrenia in remission This label was used in the Rosenhan study to diagnose all but one of the the pseudo-patients after they were discharged.  However this label is rarely used by psychiatrists.


Self report method Any method which involves asking a participant about their feelings attitudes and so on.  Examples of self reports are questionnaires, interviews and psychometric tests but note that self reports are often used as a way of gaining participants responses in observational studies and experiments.  


Self selected sampling

Self selected sampling (or volunteer sampling) consists of participants becoming part of a study because they volunteer when asked or in response to an advert.   This sampling technique is used in a number of the core studies, for example Milgram (1963).

This technique, like opportunity sampling, is useful as it is quick and relatively easy to do.  It can also reach a wide variety of participants.  However, the type of participants who volunteer may not be representative of the target population for a number of reasons.   For example, they be more obedient, more motivated to take part in studies and so on.


Shaping One of the training methods used with Washoe whereby successive approximations of behaviour is rewarded gradually until the correct sign is made. 


Situational attribution This explains behaviour in terms of aspects of the situation that a person is in rather than the person's internal characteristics such as personality.   See also dispositional attribution


Snap shot study

A snap shot study is a study carried out over a very short period of time such as hours and days.   In comparison a longitudinal study is carried out over a longer period of time such as weeks, months or years. 

Snap shot studies are obviously quicker and cheaper to carry out than longitudinal approaches and rarely suffer from attrition.  However they only provide us with a ‘snapshot’ of human behaviour and experience and therefore are not so useful when investigating development.


Snow ball sampling

Snowball sampling can be used if your population is not easy to contact.  For example if you were interested in studying students who take illegal drugs you may ask a participant who fits your target population to tell their friends about the study and ask them to get in touch with the researcher and so on.  


Social control The issue of social control refers to the attempt to influence behaviour and how people perceive their world.   Psychological research can help us understand how processes of social control operate.  For example, Milgram's study shows us how people in authority can abuse their power, and Rosenhan's study demonstrates the powerful impact that labelling can have on people.
Also of interest is how psychological research has been used by others to aid social control.  For example, it could be argued that Milgram's work could be used by those in positions of authority to further the social control of others.  Gould demonstrates how the work of psychologists such as Yerkes have been used as a form of political and 'racial' oppression.


Social learning theory Social learning theory emphasises the role of observation and imitation of role models during learning.  In general, social development is seen as a continuous learning process, rather than as happening in stages.


Split-brain patients Patients who have undergone disconnection of the cerebral hemispheres.  This is normally done in only extreme circumstances such as to prevent a seizure from spreading from one hemisphere to the other. Sperry's participants had all undergone hemisphere deconnection because they had a history of advanced epilepsy which could not be controlled by medication.


Split-style drawings Split drawings are drawings that depict the essential characteristics of an object even if all those characteristics cannot be seen from one perspective - if you like, unfolded. 



Statistics are a method of summarising and analysing data for the purpose of drawing conclusions about the data.  

Carrying out psychological research often involves collecting a lot of data.   As psychologists therefore we need to have knowledge of statistics so that we can make conclusions about our data.

We can make a distinction between descriptive and inferential statistics.   Descriptive statistics simply offer us a way to describe a summary of our data. 

Inferential statistics go a step further and allow us to make a conclusion related to our hypothesis.



Stratified sampling

Stratified sampling involves classifying the population into categories and then choosing a sample which consists of participants from each category in the same proportions as they are in the population.   For example, if you wanted to carry out a stratified sample of students from a sixth form college you might decide that important variables are sex, 1st or 2nd years, age, have a part-time job and so on.  You could then identify how many participants there are in each of these categories and choose the same proportion of participants in these categories for your study.

The strength of stratified sampling is therefore that your sample should be representative of the population.  However, stratified sampling can be very time consuming as the categories have to be identified and calculated.  As with random sampling, if you do not have details of all the people in your target population you would struggle to conduct a stratified sample. 

If the sample is not randomly selected from the categories it is then called a quota sample.

Structured observation A structured observation is where the researchers design a type of coding scheme to record their behaviour.  Structured observations generally provide quantitative data.  See also unstructured observation.



Tajfel (1970) The aim of Tajfel’s experiment was to demonstrate that putting people into groups (categorisation) is sufficient for people to discriminate in favour of their own group and against members of the other group.

The study consisted of two laboratory experiments.  

The First Experiment (under-estimators and over-estimators)

The participants were 64 boys, 14 and 15 years old from a comprehensive school in a suburb of Bristol.   The participants came to the laboratory in separate groups of 8.  All of the boys in each of the groups were from the same house in the same form at the school, so that they knew each other well before the experiment.

At first the boys were brought together in a lecture room and were told that the experimenters were interested in the study of visual judgements.  Forty clusters of varying numbers of dots were flashed on a screen and the boys were asked to record each estimate in succession on prepared score sheets.

The boys were categorised into groups of ‘over-estimators’ and ‘under-estimators’ (or into accurate/less accurate).   However the participants were actually assigned to groups at random.

The participants were taken to separate cubicles and told which group they were in.  The boys were given a booklet of matrices and told that the task would consist of giving to others rewards and penalties in real money.  The boys would not know the identity of the individuals to whom they would be assigning these rewards and penalties since everyone would be given a code number.

The value of each point they were rewarding was a tenth of a penny.

Each row of the matrix was labelled “These are reward and penalties for member no. ..... of your group”  or “..... of the other group”.  The participants had to indicate their choices by ticking one box in each matrix.

The boys were required to make three types of choice.

1.      There were in-group choices, where both top and bottom row referred to members of the same group as the boy. (other than himself)

These are reward and penalties for member no 7 of your group








These are reward and penalties for member no 8 of your group










2.     There were out-group choices, with both top and bottom row referred to members of the different group from the boy.

These are reward and penalties for member no 5 of the other group








These are reward and penalties for member no 4 of the other group










3.     There were intergroup choices, where one row referred to the boys’ own group and one row referred to the other group.

These are reward and penalties for member no 5 of the other group








These are reward and penalties for member no 4 of your group









Tajfel found that when the boys were choosing between two boys in the same group, choices tended to be made on the basis of maximum fairness.  (For example in the 1st and 2nd matrices above it would be the shaded pair of scores)

When the choice was between one boy in their ingroup and one boy in their out group the boys discriminated in favour of the ingroup.  (For example in the 3rd example above it would be the shaded pair of scores).

The first experiment therefore shows that in making their intergroup choices a large majority of the participants gave more money to members of their own group than to members of the other group.  Intergroup discrimination was the strategy used in making intergroup choices.

In contrast the in-group and out-group choices were closely distributed around the point of fairness.

The Second Experiment (aesthetic preference)

The second experiment was very similar to the first.  48 new boys were used as participants and all the participants knew each other well.  

The experiment differed in two ways.

This time the boys thought they were categorised by their preference of paintings by Paul Klee and Wassily Kandinsky.  In fact half of the participants were assigned at random to the ‘Klee group’ and half to the ‘Kandinsky group’.

The other major difference was in the type of matrices used.  In this experiment matrices were used which allowed the experimenters to investigate three variables.  The three variables were:

1.      maximum joint profit - where boys could give the largest reward to members of both groups;

These are reward and penalties for member no 4 of your group






These are reward and penalties for member no 5 of the other group






In the matrix above a boy would be following the strategy of maximum joint profit if he picked the shaded pair of numbers.


2.      largest possible reward to in-group - where the boys could choose the largest reward for the member of their own group regardless of the reward  to the boy from the other group;

These are reward and penalties for member no 4 of your group






These are reward and penalties for member no 5 of the other group






In the matrix above a boy would be following the strategy of largest possible reward to in-group if he picked the shaded pair of numbers.


3.      maximum difference - where boys could choose the largest possible difference in reward between members of the different groups (in favour of the in-group)

These are reward and penalties for member no 4 of your group






These are reward and penalties for member no 5 of the other group






In the matrix above a boy would be following the strategy of maximum difference if he picked the shaded pair of numbers.

The results of the second experiment demonstrated that the most important factor when the boys made their choices was maximising the difference between the two groups (in favour of their own group)

The experiments carried out by Tajfel therefore clearly demonstrate that inter-group discrimination is easy to trigger off. Tajfel demonstrates that the very act of categorisation into groups is enough to produce conflict and discrimination.

In a later study Tajfel uses Social Identity Theory (SIT) as an explanation for intergroup discrimination.  Social identity theory argues that the boys favoured their own group because it increases their self-esteem.  Even though the boys were never giving points to themselves they knew that if they gave less to the other group and more to their own group that they would be in the group which gained most points therefore improving their self esteem because they belonged to the ‘best’ group.

Tajfel, H. (1970)  Experiments in intergroup discrimination.  Scientific American, 223, 96-102

Theory of mind

The ability to understand that other people have independent minds of their own.

Developing a theory of mind allows a child to begin to understand other people, and to predict what other people are likely to do and believe.  It is the ability to think about other peoples, or one's own thoughts.

Simon Baron-Cohen argues that autistic people do not seem to develop a theory of mind. 


Two-factor theory of emotion Schachter and Singer developed the two-factor theory of emotion.  The two-factor theory suggests that emotion comes from a combination of a state of arousal and a cognition that makes best sense of the situation the person is in.  For example, the two-factor theory of emotion argues that when people become aroused they look for cues as to why they feel the way they do.

The two-factor theory of emotion has been an influential theory of emotions.  However subsequent work has shown that the relationship is more complex than the two-factor theory predicts.

For example many psychologists now argue that peoples efforts to understand an unexplained state of arousal is more extensive than a quick examination of cues in the surrounding environment.  When we seek to explain a state of arousal, we do not merely use others’ behaviour but call on many other sources of information as well, particularly our own past history - we search for prior occasions on which we felt this arousal state to explain its occurrence now.  



Unconscious According to Freud, this is the part of your mind which contains information that is very hard to get at and difficult to bring into our conscious awareness.


Undisclosed observation A type of observational study whereby the participants are not fully aware that they are being studied. 


Unstructured observation An unstructured observation simply involves the researchers recording the behaviour they can see.   This can be difficult without the use of recording equipment (such as a video camera), can be difficult to analyse but does provide rich qualitative data.   See also structured observation.


Usefulness of psychological research Whether psychological research is useful or not depends on our definition of useful.  Research can be useful in a number of different ways.  
It may be useful for psychologists in further understanding psychological phenomena.
Research may be useful for practitioners, for example, in areas such as, clinical psychology, health psychology, educational psychology and so on.

Research may also be useful for the general public in terms of helping them to understand themselves and their world differently.
And finally research might be useful for policy makers and politicians in helping them make decisions and formulate policy.



Validity This refers to whether a study  measures or examines what it claims to measure or examine.  (more on validity


Variables Things which can vary or change. 

Experiments attempt to manipulate one variable, the independent variable, and measure the changes to the dependent variable.

The experimenter attempts to control for extraneous variables (noise or time of day) which could effect the dependent variable.   If an extraneous variable does have an effect on the dependent variable we call this a confounding variable

Correlational analysis attempts to measure the relationship between two independent variables (or co-variables).  


Visual field If you look straight ahead and stare at an object directly in front of you, everything to the left of your nose is your left visual field and everything to your right is your right visual field.  (click here for diagram)



Wilcoxon signed rank test This is an inferential statistical test which can be used if you are carrying out a test of difference, the design is repeated measures and the data is at least at the ordinal level of measurement. 


X-axis On a scattergram the x-axis is the one that is horizontal.


Y-axis The y-axis is the vertical axis on a scattergram.


Zero correlation A zero correlation means that there is no consistent relationship between two variables.


Zimbardo (1973)

The aim of Zimbardo’s study was to investigate the effects of being assigned to the role of either a prison guard or prisoner.

The participants were respondents to a newspaper advertisement, which asked for male volunteers to participate in a psychological study of ‘prison life’ in return for payment of $15 per day.  

The 75 respondents completed a questionnaire about their family background, physical and mental health, prior experiences and attitudinal tendencies with respect to psychopathology and any involvement in crime.

Based on the results of the tests 24 men were selected.  These 24 were judged to be the most physically and mentally stable, most mature, and least involved in antisocial behaviours.  The participants were described as “normal, healthy male college students who were predominantly middle class and white.” The 24 participants did not know each other prior to the study.  The 24 participants were randomly assigned to the role of ‘prisoner’ or ‘guard’ and informed by telephone to be available at their homes on a particular Sunday when the experiment would begin.  

A simulated prison was built in the basement of the psychology building at Stanford University.  The simulated prison comprised of three small cells (each 6 x 9 ft) with three prisoners to a cell.  The cells contained three cots (with mattress, sheet and pillow) for each prisoner.  A small unlit room (2 x 2 x 7 ft) was used as ‘solitary confinement’.

Those participants allocated the role of guards had to attend an orientation meeting the day before the induction of the prisoners.  The guards were instructed in their administrative details.  However the guards were not told how to behave apart from being explicitly told that they were not allowed to use physical punishment or physical aggression.

The uniforms of both prisoners and guards were intended to increase group identity and reduce individuality within the two groups.  

The guards’ uniform consisted of a plain khaki shirt and trousers, a whistle, a police night stick (a wooden batten) and reflecting sunglasses, which made eye contact impossible.   The guards’ uniforms were intended to convey a military attitude, while the baton and whistle were symbols of control and power.  

The prisoners’ uniform consisted of a loose-fitting muslin smock with an identification number on the front and back, no underwear, rubber sandals, a hat made from a nylon stocking and they had a light chain and lock around their ankle.  Each prisoner was also issued with a toothbrush, soap, soap-dish, towel and bed linen.  No personal belongings were allowed in the cell. The prisoners’ uniforms were designed to de-individuate the prisoners and to be humiliating and serve as symbols of subservience and dependence. 

The prisoner participants were unexpectedly ‘arrested at their homes with the cooperation of the local police department.  A police officer then charged them with suspicion of burglary or armed robbery, advised them of their rights, handcuffed them, thoroughly searched them (often in full view of their neighbours and passers by) and drove them in the back of a police car to the police station.  

At the police station they had their fingerprints and photograph taken and were put in a detention cell.  Each prisoner was then blindfolded and driven to the mock prison by one of the experimenters and a guard.  Throughout this arrest procedure, the police officers involved maintained a formal, serious attitude, and did not tell the participants that this had anything to do with the mock prison study.

At the mock prison, each prisoner was stripped, sprayed with a delousing preparation (a deodorant spray) and made to stand alone and naked in the ‘yard’.  After being given their uniform and having a mug shot (ID picture) taken, the prisoner was put in his cell and ordered to remain silent.

The warden read them the rules of the institution (developed by the guards and the warden), which were to be memorised and had to be followed.  Prisoners were to be referred to only by the number on their uniforms, also in an effort to depersonalise them.  

Every day the participants were allowed three bland meals, three supervised toilet visits, and given two hours for the privilege of reading or letter writing.  Work assignments had to be carried out and two visiting periods per week were scheduled, as were movie rights and exercise periods.  

Three times a day prisoners were lined up for a ‘count’ (one on each guard work-shift).  The original purpose of the ‘count’ was to establish that all prisoners were present, and to test them on the knowledge of the rules and their ID numbers.  The first ‘counts’ lasted only about ten minutes but as conditions in the prison deteriorated, they increased in length until some lasted for several hours.  

The results showed that the behaviour of the ‘normal’ students who had been randomly allocated to each condition, was affected by the role they had been assigned, to the extent that they seemed to believe in their allocated positions.

The guards became more and more verbally and physically aggressive.  Zimbardo described this as pathology of power. The prisoners became increasingly depersonalised and several experienced extreme emotional depression, crying, rage and acute anxiety.

The experiment had to be stopped after just six days instead of the planned 14 days, mainly because of the pathological reactions of the participants.  Five prisoners had to be released even earlier because of extreme emotional depression.

Zimbardo believes that the study demonstrate the powerful effect roles can have on peoples’ behaviour.  Basically the participants were playing the role that they thought was expected of, either a prisoner or prison guard.

Haney, C., Banks, W.C. & Zimbardo, P.G. (1973) A study of prisoners and guards in a simulated prison. Naval Research Review, 30, 4-17.




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