Why do people conform?
People match the judgements and choices of others for two reasons that experiments can tell apart: to get things right and to get along.
Answer to the question
Why do people conform?
People conform for two main reasons that researchers separated in 1955: others supply evidence when a situation is unclear, and others offer approval to those who match them. Experiments from a 1935 dark-room study to a 2014 study of two-year-olds show both, and children switched more when the peers they copied were still present.
Key takeaways
- Sherif's dark-room experiment (1935) used a light that appears to drift: individuals judging alone settled on very different values, group members converged on a shared one, and only about a quarter thought others had influenced them.
- Deutsch and Gerard (1955) separated informational influence, accepting others as evidence, from normative influence, matching others because their approval matters.
- Berns and colleagues (2005) found errors of about 41 per cent when a human group was wrong and about 32 per cent when a computer was wrong, against about 14 per cent at baseline.
- In Berns's scanner study, conforming to the group went with activity in visual and parietal regions, while resisting it went with activity in the right amygdala and caudate.
- Haun and colleagues (2014): 12 of 18 two-year-olds switched to what peers showed on the first trial, against 2 of 12 chimpanzees and 2 of 12 orangutans, and children switched more when the demonstrators were still present.
Muzafer Sherif's participants sat in a dark room more than ninety years ago and judged how far a fixed point of light seemed to wander, an illusion that leaves people nothing to judge by except one another. Over repeated sessions, participants who began far apart in their estimates of the drift moved toward a shared value, and many then kept it.
People conform for two broad reasons, and experiments have been able to tell them apart by changing what others can offer. Others can supply evidence when a situation is unclear, and others can supply approval to the person who matches them, so conformity can be a way of being right or a way of belonging.
A Light That Never Moved and Two Kinds of Influence
The set-up was spare. Sherif seated male students in a sound-proof dark room, five metres from a small light hidden behind a screen so that nothing hinted at its distance. When they pressed a key to say the light had moved, it went out two seconds later. The movement they reported was a perceptual illusion, which is now called the autokinetic effect, and it left each person with a range of drift and a typical value inside that range.
Judging alone, the nineteen participants in the first experiment settled on very different typical values, from under half an inch to nearly ten inches. People who then joined a group drifted toward one another, and their medians narrowed over the sessions. People who began in a group converged almost at once, and the shared level held across later sessions. Groups of two and groups of three behaved alike.
The lasting part came afterwards. Members who had started in a group kept a norm close to the group's when they were tested alone again, while pairs who had started alone remained further apart. Most participants did not think other people's judgements had influenced them. The other voices were the only measuring instrument in the room, and participants used them.
A paper by Morton Deutsch and Harold Gerard drew a line through that territory in 1955, and their distinction has outlasted most of the surrounding theory. Informational influence is accepting what others say or do as evidence, and normative influence is matching others because their approval matters. Sherif's room is the cleanest case of informational influence, since the light offered no answer but the group's. Most real situations carry both, and each can produce the same outward conformity, which is why the distinction is useful.
The two make different predictions about an audience. Evidence stays evidence whether or not anyone is watching, while approval only matters if someone can give or withhold it, so a study that changes who is present can begin to pull them apart.
Jonah Berger's Invisible Influence, the book this piece started from, treats imitation as one of the routes by which other people shape what we do, partly because they carry information and partly because standing out has a cost, which lines up with the two kinds of influence. Berger also discusses Solomon Asch, whose line-judgement work is covered in The Invisible Weight of Belonging, and the same two pulls are harder to separate at the scale examined in What is crowd mentality.
| Term | What it means here |
|---|---|
| Autokinetic effect | The illusion that a fixed point of light in darkness is moving, used by Sherif in 1935 |
| Informational influence | Accepting what others say or do as evidence about what is true |
| Normative influence | Matching others because their approval or expectations matter |
What Did a Scanner Show When the Group Was Wrong?
A 2005 fMRI study led by Gregory Berns took the question of why people conform inside the head. Thirty-two adults, analysed from 33 recruited, judged whether pairs of abstract three-dimensional shapes matched after mental rotation, while lying in an fMRI scanner. Before each judgement they saw the answers of four apparent peers, who were actors, and on some trials the four agreed on a wrong answer. In a separate session the answers came from computer icons said to run a simple algorithm.
Errors in the Berns study rose from about 14 per cent with no group answers to about 41 per cent when the group was wrong, against about 32 per cent when the computer was wrong. A wrong human majority moved people more than a wrong machine did, so conformity to people and to a computer were not the same thing. Conforming to the group, compared with conforming to the computer, was linked to activity in an occipital and parietal network that includes visual cortex and the right intraparietal sulcus, and not in prefrontal regions. That pattern was read as a hint that group answers can alter what a person perceives, not only what they decide to say.
Resisting the group was linked to the right amygdala and the head of the right caudate nucleus, which the team took as the emotional weight of standing apart, while calling the amygdala finding tentative because the region was small and each person contributed few conformity trials.
Two-Year-Olds, Apes and a Box With Three Holes
Whether our closest relatives share the habit of conforming to peers was tested in 2014 with a box that has three holes. Eighteen two-year-old children, 12 chimpanzees and 12 orangutans each learned by trial and error that one section of a three-hole box gave food. Three familiar members of their own species then showed a different section that worked equally well, and the participant chose where to drop its balls.
Children switched to the demonstrated section in more than half of all their choices. On the first test trial, 12 of 18 children switched, against 2 of 12 chimpanzees and 2 of 12 orangutans. The apes mostly kept to what they had learned themselves, and only the children conformed above chance. Daniel Haun and his co-authors could not exclude general conservatism in the apes as an explanation, and they suggested the difference might help account for why human cultures vary so widely.
A second study with 72 children changed one thing: whether the demonstrators stayed or left before the child chose. Children switched more when the demonstrators were still present, which the authors took as evidence that social motives were part of the story. The number of demonstrators made no difference, and one peer moved a child about as often as three.
Common questions
Why do people conform?
People conform for two main reasons that Deutsch and Gerard separated in 1955. Others can be evidence about what is true when a situation is unclear, and others can offer approval for matching them. Experiments from Sherif's dark room to peer-copying in two-year-olds show both.
What is the difference between informational and normative influence?
Informational influence means accepting what others say or do as evidence about reality. Normative influence means matching others because their approval or expectations matter. Sherif's 1935 light experiment is mostly informational, because the group was the only guide to the light's movement.
Do children conform?
In Haun and colleagues' 2014 study, two-year-olds switched to what peers showed in more than half of their choices, and switched more when the peers were still present. Chimpanzees and orangutans in the same design mostly kept their own approach.
Sources
Berger, J. (2016). Invisible Influence. New York: Simon & Schuster. Seed book; vault hub Books/Invisible Influence.
Sherif, M. (1935). “A study of some social factors in perception.” Archives of Psychology, 187. New York: R. S. Woodworth. No DOI; library catalogue record https://bdu.siu.edu.ar/bdu/Record/B-53-152302
Deutsch, M., & Gerard, H. B. (1955). “A study of normative and informational social influences upon individual judgment.” Journal of Abnormal and Social Psychology, 51(3), 629-636. doi:10.1037/h0046408 https://doi.org/10.1037/h0046408
Berns, G. S., Chappelow, J., Zink, C. F., Pagnoni, G., Martin-Skurski, M. E., & Richards, J. (2005). “Neurobiological correlates of social conformity and independence during mental rotation.” Biological Psychiatry, 58(3), 245-253. doi:10.1016/j.biopsych.2005.04.012 https://doi.org/10.1016/j.biopsych.2005.04.012
Haun, D. B. M., Rekers, Y., & Tomasello, M. (2014). “Children conform to the behavior of peers; other great apes stick with what they know.” Psychological Science, 25(12), 2160-2167. doi:10.1177/0956797614553235 https://doi.org/10.1177/0956797614553235