Monday, 28 September 2015

Introvert v's Extravert Personalities

An introvert is a person who prefers solitude or 1-to-1 interactions rather than busy social occasions, while an extravert is the opposite - they like to socialise, and don't particularly like to be alone.


However, this is a very simplistic distinction - most people really fall on a scale from one extreme to the other, with few of us entirely introverted or extraverted. Sometimes researchers use the term 'ambivert' to mean someone who is more or less equally balanced between the two.

The following image illustrates this idea of a scale between two extremes:

Introversion v's extraversion. Source: here.

Biological basis

According to researcher Hans Eysenck (1967), some people have a less sensitive nervous system than others do, and therefore need more environmental input for the same end result. They therefore need more social interaction in order to feel stimulated causing them to be extraverted, while those with more sensitive nervous systems feel overwhelmed with too much input, and therefore avoid it i.e. they are introverted. This biological theory is supported by evidence suggesting that personality appears early in life, and that personality traits remain steady over the lifespan (McCrae & Costa, 1997).

Social factors

The work of McCrae and Costa (1997) suggests that personality factors including extraversion are universal, and therefore relatively little influenced by culture. The society that we live in does make a difference to whether traits are encouraged or even accepted, however; in her 2013 book 'Quiet', Susan Cain argues that society increasingly values the extravert, with introverts being misunderstood and undervalued.

From a teaching point of view, it is undoubtedly true that the typical classroom today - with discussions, debates, and a social-constructivist approach to learning in general - is more geared to the extravert than to the introvert.


Eysenck, H. J. (1967). The Biological Basis of Personality. Springfield, IL: Thomas Publishing.
McCrae, R.R. and Costa, P.T. Jr (1997). Personality trait structure as a human universal. American Psychologist, 52(5), 509-516.

Monday, 1 June 2015

Help for Psychology Students

This site aims to provide useful information for Psychology students, especially in introductory courses such as GCSE, N5, Higher, A-Level and the early years of college or university study. It provides summaries of many classic Psychology research studies and theories. Some of the most popular posts can be seen in the sidebar, or use the search menu at the top of the screen to search by keyword. This is brought to you free of charge and without adverts. Comments are very welcome.

Some items that previously appeared on this blog - especially articles on educational theory - are now on my personal website,

Sunday, 31 May 2015

Kozorovitskiy et al (2006)


Marmosets are small monkeys, and are unusual among primates because males care extensively for their offspring. Kozorovitskiy et al. (2006) wanted to find out what effect this had on the monkey fathers' brains.


The researchers found that becoming a father resulted in important changes in the brains of male adult marmoset monkeys. Changes were found in the dendrites - the branching spines that connect neurones - in the frontal lobe of the monkey's brains. These were more complex than those of a control group of marmosets who were in mating pairs but were not fathers. 

Marmoset monkeys are good dads. Image by Tambako the jaguar


The changes could be explained in terms of the complex cognitive demands in caring behaviour, but the researchers noted a possible connection to the hormone vasopressin. The also note that the functional consequences of the change are not yet clear.

Human males, depending on culture, often play a major role in child rearing, and this finding has potential implications - with the usual caution about generalising cross-species.


Kozorovitskiy, Y., Hughes, M., Lee, K., and Gould, E. (2006). Fatherhood affects dendritic spiness and vassopressin V1a receptors in the primate prefrontal cortex. Nature Neuroscience, e9, 1094 - 1095. doi:10.1038/nn1753

Saturday, 30 May 2015

The Biological Approach

The biological approach to psychology is a contemporary approach which emphasises how processes within the body affect our thoughts and behaviour. It relates directly to the medical model of atypical behaviour, which explains mental illness in terms of bodily processes, and treats them using drugs.

Main principles

The approach tries to explain our behaviour in terms of 4 main biological systems:

  • The nervous system
  • Hormones
  • Genes

Of these, the most important is the nervous system - the nerves of the body, including the brain and spinal cord. It seems obvious to say that the brain controls behaviour - nobody in Psychology argues this point. However non-biological psychologists can take a 'black box' approach to the brain, saying that we don't need to study it directly in order to understand thoughts or behaviour.

Brain areas

Early ideas about the role of different brain areas were based on case studies of people who had suffered injuries or illnesses that damaged their brains, resulting in loss of specific psychological functions. One was the case of Phineas Gage - a man who survived a huge brain injury to his frontal lobe, but suffered a resulting personality change including a loss of self-control. Another was Paul Broca's patient 'Tan' who lost the ability to speak after losing a particular area of the left hemisphere which became known as Broca's area.

Nowadays, researchers have developed a much more sophisticated understanding of what areas of the brain do. One essential tool is the use of modern brain scans such as fMRI and PET scans, which allow the activity level of a person's brain to be seen on a screen at the same time as they are doing a task. Areas which 'light up' more are assumed to be important to the task. For example, if the frontal lobe lit up during a problem solving task, this would be evidence that this area of the brain is involved in problem solving.

An image from a PET scan of the brain. Photo by Reigh LeBlanc.

Brain cells

This approach views all psychological activity as fundamentally the product of brain cells communicating with each other. This happens through electrical impulses in a neurone travelling down the axon (nerve fibre) and then triggering the release of chemicals called neurotransmitters. Any time a person takes a drug such as caffeine, alcohol or cocaine, the drug is interfering with this process in some way - for example, by mimicking the neurotransmitter and making certain brain areas more active.

(Read more about how neurotransmitters work here).

Hormones and genes

Both hormones and genes have also been linked to behaviour. For example, in the area of atypical behaviour/psychopathology, disorders such as post-natal depression have been linked to a hormonal imbalance, while a range of disorders including schizophrenia have been shown to correlate to genetic factors - for example, if you have an identical twin with the disorder, then you are more likely to have it too. However, nobody has yet found 'the schizophrenic gene', as such.


With all of the biological factors that link to Psychology, there is a question of cause and effect. For example, if someone with a mood disorder has an atypical hormone or neurotransmitter level, is this the cause of their disorder, or is it a result of it?

Brain scans can be misleading - and may link to the over simplistic idea that a psychological function happens in one part of the brain. In fact, it may be better to think of processes as the result of communication between brain areas, rather than occurring a single place. The technology has also been shown to be at risk of false positives - such as showing activity in the brain of a dead salmon!

This approach has been accused of being reductionist - arguably, we can find more and more detail about the brain without really answering the big questions about Psychology.

Increasingly, this approach is making broad links across the subject. Cognitive neuroscience is the study of how cognition occurs in the brain, while social neuroscience means the study of how thought processes link to brain function.

See also this recent BPS digest article - Students seduced by superfluous neuroscience.

Friday, 22 May 2015

A Behavioural Sink: Calhoun's (1962) rat studies

Aggressive gangs of youths, neglectful parents, sexual assault - some of the worst aspects of modern human society. But could they simply be the products of the physical environment we live in?

That is exactly what researcher James Calhoun suggested with his groundbreaking studies on rodents - which found many of the same social problems cropping up in artificial and overcrowded 'rat cities' that he created in his lab.

What happens to a rat's behaviour when it is overcrowded? Image via Pixabay


The most obvious problem the rats suffered from was overcrowding. Things started off well with a total population of 48 rats across 4 enclosures, but they soon began to breed and multiply despite the limited space. The social structures that emerged were put under pressure, with it hard for any of the rats to defend their territory.

Psychological space

Interestingly, it was not just the size of the physical space that impacted on behaviour, but its layout. With the pen divided into four compartments, two were 'end' compartments with a single entranceway, and the remaining two were of equal size and shape, but had a pair of entrances, joining on to the other pens. The results in the two types of compartment were sharply contrasting. In the end compartments, a single male rat was able to dominate a territory, guarding the single entrance and keeping rivals out. Within these compartments, behaviour was essentially normal.

However in the middle compartments, this wasn't possible. It was here that the rats' behaviour degenerated so disturbingly:

- Male rats formed 'gangs' and attacked females and infants

- Females suffered massively increased birth complications

- Infants were forgotten or abandoned

- Some rats wounded, sexually attacked or even cannibalised other rats.

The rats changed so markedly that their behaviour was unrecognisable compared to rats in a more natural habitat - according to Calhoun, they had "stopped being rats".

What do people (and rats) need?

There will always be doubts about comparing animal experiments to humans, but this study had a huge impact because it seemed to tell us something profound about behaviour and psychological health.

The research strongly suggests that the answer to psychological health is not within our brains but within our environments - if our surroundings are positive, it seems to suggest, the chances of deviant and antisocial behaviours may be greatly reduced.

Read more

The social implications of Calhoun's work: 'Letting the Rat out of the Bag'
A similar study with implications for addiction: 'The View from Rat Park'.


Calhoun, J. B. (1962). Population density and social pathology. Scientific American, 206(3), 139–148.

Discussion points:

  • Was this study unethical?
  • Can the rat behaviour in the study be generalised to human behaviour?
  • What human environments might be similar to the 'middle compartments' in the study where most harmful behaviour was observed? 

Wednesday, 20 May 2015

Hazan & Shaver (1987) - the 'Love Quiz' study


Hazan and Shaver (1987) studied adult relationships to find out whether romantic love shows the same attachment styles as those found among children.

Like Bowlby, they believed that an infant’s attachment to the primary carer provides a schema of how relationships work that will be carried into adulthood. The implications of this, which they set out to test, is that similar attachment styles may be shown in adulthood as Ainsworth and Bell (1970) discovered among infants.

Can childhood attachments lead to adult
romantic behaviour? Image by Robert McGoldrick.


The researchers used a survey printed in a newspaper, presented as a “love quiz”. The first 620 responses were analysed – 205 from men and 415 from women. 42% of participants were married and 31% were dating. Questions asked about issues such as fear of closeness, jealousy and obsessive preoccupation.


The researchers analysed the responses to the questions and categorised each participant into one of three groups:
  • Securely attached: has a healthy balance between wanting closeness and being comfortable with independence.
  • Avoidant: tends to avoid closeness and is excessively independent, i.e. dislikes relying on others.
  • Anxious: clingy and insecure; is very uncomfortable with independence.
From the sample, 56% were secure, 25% avoidant and 19% anxious. These are very similar to the proportions of secure/insecure infants in the classic studies by Ainsworth and colleagues - supporting the researchers’ hypothesis.


A limitation is that there is no way of knowing if the same individuals who report secure adult relationships were also securely attached as children. Therefore, although the results did in principle support the researchers' continuity hypothesis of attachment styles through the lifespan, they didn't confirm it.

However, as the first attempt to link attachment style to adult relationships, this was a large-scale study and very successful.


Ainsworth, M.D.S. & Bell, S.M. (1970). Attachment, exploration, and separation: Individual differences in strange-situation behavior of one-year-olds. Child Development, 41, 49-67.
Hazan, C. and Shaver, P.R. (1987). Romantic love conceptualised as an attachment process. Journal of Personality and Social Psychology, 52(3), 511-524.

Monday, 18 May 2015

Why do we Conform?

To define it broadly, conformity means changing our behaviour to become more similar to those around us. More specifically, the change should come from the social pressure exerted by other people (not necessarily intentionally), rather than simply from social facilitation. It also tends not to involve a direct order or request.

Therefore conformity can be defined as ‘social pressure, usually unspoken, to change our behaviour or beliefs in order to come into line with others in a group.’

Clothing often demonstrates conformity. Image by Celine Nadeau

Types of Conformity

Conformity involves a change in behaviour, but not always a change in attitudes. Psychologists distinguish between three types of conformity (Kelman, 1958):

  • Compliance. Here the individual changes their behaviour - modifies what they do, say or wear -  without changing their beliefs. They go along with the crowd in the social situation, but maintain their own views deep down
  • Identification. Here, there is a change of attitudes and beliefs, but they are shallow and temporary. Typically, the behaviour change will only last for as long as the individual is a member of the group in question.
  • Internalisation. Here there is a permanent change of attitudes. The individual initially conforms to their group, but the new attitude or behaviour becomes part of their individual identity. This means that not only will they behave this way when on their own, but will continue to do so long after the group has ceased to exist

Motivation to Conform

Humans seem to have a strong motivation to fit in with the group. Jones (1964) considered conformity to be based on ingratiation i.e. getting other people to like and accept us. We might adjust our behaviour to what we think others will like and approve of. This is known as normative influence (Deutsch and Gerrard, 1955) and is based on a desire to be liked and not rejected by others. An example might be binge-drinking if your friends are doing it.

Some conformity doesn't seem to be motivated by the desire to be liked - for example, when the other people are strangers and we'll never see them again. Informational influence (Deutsch and Gerrard, 1955) occurs when we don't know what to do, so we look to see what others are doing. It is motivated by a desire to be right. An example could be standing in a long queue rather than a short one, because we assume that it must be there correct place to stand.

Conformity in Society

Conformity tends to be seen as a bad thing - but it can include conforming to others who are obeying the law or donating to charity. It's therefore a mixture - neither inherently good or bad. One thing that is clear about conformity is that it is found in every human society (Smith & Bond, 1993). This means it is a culturally universal process.

An assumption is often made that social influence can only work one way, i.e. the minority conforming to the majority. However, Moscovici and Lage (1976) demonstrated minority influence - the minority exerting an influence over the majority rather than the other way round - by getting two confederates (actors) among a group of six participants to describe a blue slide as green. This gradually influenced the rest of the group. Minority influence is strongest if it is consistent and unanimous. Moscovici (1981) argues that through history, most social change has resulted from a minority persuading the majority into their way of thinking.

The universal nature of conformity suggests that it is a fundamental part of human nature. Tomasello (2014) suggests that 'group-mindedness' was an evolutionary adaptation to our ancestors' reliance on one another when hunting; other apes are highly social, but for humans, conformity to group norms was so important that it became an end in itself.


Deutsch, M. and Gerrard, H.B. (1955). A study of normative and informational social influence upon individual judgements. Journal of Abnormal and Social Psychology, 51, 629-636.
Jones, E. E. (1964). Ingratiation: A Social-Psychological Analysis. New York: Appleton-Century-Crofts.
Kelman, H. C. (1958). Compliance, identification, and internalization: Three processes of attitude change. Journal of Conflict Resolution, 2(1), 51–60. doi:10.1177/002200275800200106
Moscovici, S. (1981). On social representations. In J.P. Forgas (Ed.) Social Cognition: Perspectives on Everyday Understanding. London: Academic Press.
Moscovici, S. and Lage, E. (1976). Studies in social influence III: Majority versus minority influence in a group. European Journal of Social Psychology, 6, 149-174.
Smith, P.B. and Bond, M.H. (1993). Social Psychology Across Cultures: Analysis and Perspectives. Hemel Hempstead: Harvester Wheatsheaf.
Tomasello, M. (2014). The ultra-social animal. Invited Horizon article for European Journal of Social Psychology, 44, 187-194.