Peer influence
IB Psychologyยท Human developmentยท 14 min read
1. Core concept
Peer influence is the way friends and age-mates shape a young person's attitudes and behaviour, especially in adolescence when peers' approval matters most. It can push behaviour in either direction โ encouraging risk-taking, or supporting achievement โ often by changing what the person believes is normal or high-status among peers. Peers thus become a major force in the development of self, alongside family and culture.
2. Key studies
IB Psychology answers must be supported by named studies. Learn these to cite as evidence:
Cohen and Prinstein (2006)
In a manipulated online chatroom, adolescents shifted their attitudes and willingness to behave aggressively/riskily toward the responses of peers they believed were high-status. โ An experimental demonstration โ manipulating perceived peer norms changed behaviour, evidence for genuine influence rather than mere similarity.
Giletta et al. (2021)
A meta-analysis of longitudinal studies found a small but robust and statistically significant effect of peer influence on adolescents' behaviour across countries and ages. โ Shows the effect is real and general, while quantifying that it is modest.
3. Evaluation (AO3)
Strength โ experimental and meta-analytic support โ Cohen & Prinstein establish causal direction under control, and Giletta's meta-analysis shows the effect replicates broadly โ a rare pairing of internal and external validity.
Limitation โ the effect is modest and hard to separate from selection โ The averaged effect is small, and outside experiments young people choose similar friends (selection), so correlational peer 'influence' is easily overstated.
4. Scope
5. Common Pitfalls
Wrong move:
If teenagers and their friends behave alike, the friends must have caused it (peer pressure).
Why:
A frequently penalised misconception in IB Psychology exams.
Correct move:
Similarity can come from SELECTION (similar teens befriend each other) as much as from influence. Showing peers change behaviour needs experimental or longitudinal evidence (Cohen & Prinstein; Giletta), not just a correlation.
Going deeper
- Conformitychanging behaviour to match a group is conformity (SOC_3).
- Enculturation of social normspeers are one channel through which cultural norms are enculturated (HD_6).