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 Clinical Neuroscience.
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)
Publikation: ”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
For more information about the study, please contact:
Björn Lindström, researcher
Department of Clinical Neuroscience, Karolinska Institutet
Tel: +46 70 2225 886
More information about Andreas Olsson’s research team at Karolinska Institutet at: www.emotionlab.se
Karolinska Institutet is one of the world’s leading medical universities. Its vision is to significantly contribute to the improvement of human health. Karolinska Institutet accounts for over 40 per cent of the medical academic research conducted in Sweden and offers the country´s broadest range of education in medicine and health sciences. The Nobel Assembly at Karolinska Institutet selects the Nobel laureates in Physiology or Medicine.