IB Psychology SLTopic 2 — Development of the SelfPaper 1 & 2Sociocultural approach~12 min read
Peers, Social Identity and Who You Become
Ask someone to describe themselves and listen to how fast they reach for a group. Their country, their year group, their team, their subject. Social identity theory says that is not a shortcut — it is genuinely where a large part of the self comes from.
📘 What you need to know
Social identity theory (SIT) says a person’s sense of self is built partly out of the groups they belong to.
Groups you belong to are ingroups; groups you do not belong to are outgroups.
Some ingroups are chosen (a team, a club) and some are not (nationality, age group, ethnicity).
Three key processes: social categorisation, social comparison and positive distinctiveness.
These lead to ingroup favouritism and outgroup derogation, which can become prejudice and discrimination.
Adolescents are especially open to peer influence: peers replace parents, and the teenage brain is very responsive to social rewards.
Key study: Graupensperger et al. (2018) found that student athletes who identified strongly with their team were more willing to conform to risky behaviour.
Where the self comes from, on this theory
Your identity has a personal part (I am stubborn, I am funny) and a social part (I am a swimmer, I am from Lahore, I am an IB student). SIT is about that second part, and it argues it is doing far more work than people assume.
Some of it you pick. A lot of it you do not. Nationality, the sex you were assigned at birth, ethnicity and age group all get handed to you, and each one comes with expectations attached.
The chain matters. Categorising alone is harmless mental filing. It turns into prejudice once comparison and the need for self-esteem get involved.
Social categorisation
People arrange others into groups by whatever features are handy: Millennials, Boomers, Italians, punks, science students. It happens fast because it is cheap — it takes very little mental effort compared with getting to know everyone individually.
That cheapness is exactly why it is also the starting point for stereotypes.
Social comparison
Once the groups exist, people compare their own against others to protect or boost their self-esteem.
Downward comparison: your group is seen as superior. An employed person looking down on someone unemployed.
Upward comparison: the other group is seen as superior. A small business owner admiring a billionaire entrepreneur.
Positive distinctiveness
People emphasise what is good about their own group to make it stand out. And a strange asymmetry appears: your ingroup looks full of different individuals, while the outgroup looks like copies of each other.
Once a group is seen as one undifferentiated mass, individual members stop being individuals. That is the psychological step that makes discrimination feel reasonable to the person doing it.
Why adolescents are the most affected
Social identity matters at every age, but it is turned up loudest in the teenage years, for three reasons that stack on top of each other.
1
PEERS TAKE OVER
Friends replace parents as the main source of influence
2
SOCIAL REWARDS
The teenage brain reacts strongly to approval and acceptance
3
NEED FOR APPROVAL
Wanting to be accepted motivates conformity
4
STATUS COPYING
High-status members get imitated and amplified
5
RISK FOLLOWS
Group norms can pull behaviour towards risk
Link this straight back to the first page of the topic. The prefrontal cortex — the braking system — is the last part to mature, while the reward system is already fully online. Social identity supplies the pressure; brain maturation explains why it works so well on teenagers.
The key study
KEY STUDY
Graupensperger et al. (2018) — team identity and risky behaviour
Aim
To investigate whether college athletes who identify strongly with their team are at greater risk of conforming to their teammates’ risky behaviour.
Sample
379 student athletes from US college sport, mean age 19, roughly balanced between male and female, across 23 sports including baseball, soccer, lacrosse and field hockey. Most were in their first year.
Method
Participants read hypothetical risky scenarios, such as being offered marijuana, and said how they would respond.
They were then shown fictional teammate responses that appeared to show strong agreement with the risky option.
They were given a chance to answer the same scenarios again and change their original answers.
A focus group with seven recently graduated athletes explored their real experiences of these situations.
Findings
Athletes with higher levels of social identity were more willing to shift towards risky behaviour such as binge drinking, marijuana use and drink driving. Those on high-identity teams were also more willing to hide a concussion so they could keep playing.
Conclusion
A strong social identity is built by aligning your behaviour with the group’s, and the stronger that identity, the more likely a person is to conform — even when the group norm is harmful.
The concussion finding is the one to quote. It shows conformity beating self-interest — athletes were willing to risk their own health to stay part of the group. That is a far stronger illustration of the theory than the drinking data.
Evaluating social identity theory
Strengths
Limitations
Robust. Supported by decades of studies using both statistical testing and qualitative research.
Too simple. People do not always favour their ingroup; plenty actively dislike or reject a group they belong to.
Good applications, including anti-bullying programmes that build a positive shared identity for the whole student body.
Limited generalisability. Graupensperger used US college athletes, who are competitive and loyal by definition.
Explains prejudice without needing to assume anyone involved is unusually hostile.
Hard to measure. Group identities are unstable and change with context, so they are difficult to pin down.
Works at any scale — a sports team, a school, a nation.
Self-report and hypothetical scenarios may not match what people would actually do.
Link to concepts
Perspective: strong social identity is not automatically bad. In the same study it also predicted conformity to prosocial behaviour, such as being helpful. That means the effect can be harnessed deliberately.
Causality: it is hard to say where group membership stops and identity begins. Someone can support a football club hundreds of miles from where they live and never have been there — so what exactly created the identity?
Measurement: asking about hypothetical scenarios measures stated intentions, not behaviour.
Exam practice
EXAM QUESTION
Discuss the role of peers in the development of self. [22]
Keep the theory and the peer material joined up. An essay that explains SIT and then separately mentions teenagers rarely reaches the top bands.
Define social identity
Part of the self comes from group memberships; ingroups and outgroups.
Explain the three processescategorisation → comparison → positive distinctiveness → ingroup favouritismApply it to adolescence
Peers replace parents, brain is sensitive to social reward, high-status members get copied.
Support with research
Graupensperger et al. (2018): 379 athletes, fake teammate responses, higher identity meant more conformity, including hiding concussion.
Evaluaterobust theory + real applications, but narrow sample + hypothetical scenarios + people sometimes reject their ingroupsJudgement: peers shape the self powerfully, but not only in harmful directionsthe prosocial finding is what turns a good essay into a balanced one
💡 Exam tips
Use the three process names in order. Examiners are looking for the sequence, not just the words.
Give a specific ingroup and outgroup example. Something ordinary from school works better than an abstract one.
Learn the concussion finding — it is memorable and it does more analytical work than the drinking data.
Tie peer influence to brain maturation if you can. Cross-topic links score well.
Distinguish upward and downward comparison. Students often mention comparison without saying which kind.
Always include the prosocial side. It stops the essay reading as one-sided.
⚠ Common mix-ups
Thinking SIT is only about prejudice. It is a theory of identity; prejudice is one consequence.
Confusing personal and social identity. SIT is about the group-based part of the self.
Saying categorisation causes discrimination on its own. It needs comparison and the self-esteem motive.
Assuming all ingroups are chosen. Nationality, age group and ethnicity are handed to you.
Reversing upward and downward comparison. Downward means looking down; upward means looking up.
Treating Graupensperger as proof about all teenagers. It was US college athletes responding to hypothetical scenarios.
Up next: How Childhood Poverty Shapes Development — from the groups a child belongs to, to the material conditions they grow up in, and what those conditions do to development.
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