Karolinska: The threat of punishment combined with people’s willingness to copy others – this is the basis for a new psychological model that can describe how traditions and norms are created and maintained. Scientists have shown that animals learn from each other through social learning when there is approaching danger. For example, information about an imminent predator spreads through a flock of birds which then collectively reacts and flees. Yet, the role of social learning in avoiding danger has not been studied specifically in humans.
“We wanted to find out how these situations function in humans
when we need to avoid danger. We discovered that two separate, simple,
psychological mechanisms – the copying of others behaviour and the
rewarding properties of avoiding danger together forms a potent driving
force that helps explain how we can create and maintain norms and
traditions,” says Björn Lindström, researcher at the Department of
Along with research leader Andreas Olsson, he conducted four
experiments that included 120 test subjects. In the first experiment,
the study participants were asked to choose between two pictures, A and
B, on a screen 20 times. They were told that an unpleasant electric
shock (which they had felt beforehand) would be given if they made the
wrong choice. In reality, however, no electric shocks were given for any
answer. Before making their choice, the subjects were shown a video
clip of another person faced with the same choice, without being shown
the consequence of the decision. The person in the video choose picture A
each time. And so did the subjects in more than 95 percent of their
choices. When the subjects were instead promised a reward – a chance to
win movie tickets – they adhered to the video person's example in only
60 percent of cases. In an experiment where there was the threat of an
arbitrary punishment, adherence to the example in the video dropped to
below 70 percent.
“Our conclusion is that when we are promised a reward, we are
more inclined to break the pattern, and social learning tends to play a
smaller role. But when it comes to avoiding danger, social learning has a
powerful influence on our behaviour when it is proved to yield good
results. But in cases where social learning is shown not offer effective
protection from danger, we are also more inclined to break the
pattern,” says Andreas Olsson, docent and research team leader at
the Department of Clinical Neuroscience at Karolinska Institutet.
In the fourth study, the researchers wanted to find out whether
the inclination to choose only option A could be passed down from one
person to the next, under the perceived threat of an electric shock. Ten
subjects were separately shown the video in which the person choose
option A and were asked to make their choice. Ten new test subjects were
then shown video of the choice made by one of the first test subjects,
without knowing what the consequence would be. When five generations of
test subjects had made their choices after watching someone from the
previous generation make their choice, picture A remained the chosen
alternative in 95 percent of answers.
“These mechanisms might help to explain how certain arbitrary
traditions can be created and maintained, such as taboos about clothes
or forms of behaviour which have no real significance to the group or
individual. In this case we created a "choose option A" tradition which
remained strong after five generations. Arbitrarily prohibiting certain
types of food, for example, that do not need to be avoided for any
particular reason, could be maintained because the individuals in the
group will tend to fear the disapproval of their group peers if they ate
the forbidden food,” says Björn Lindström.
The study was funded by the Swedish Research Council and the European Research Council (ERC 284366, ELSI)
”Mechanisms of Social Avoidance Learning Can Explain the
Emergence of Adaptive and Arbitrary Behavioral Traditions in Humans”.
Björn Lindström och Andreas Olsson.
Journal of Experimental Psychology: General
, online 13 April 2015, doi: 10.1037/xge0000071