I thought of this Carlin bit while reading this... thought I'd share it.
http://www.sciencedaily.com/releases/2012/01/120131210259.htm
ScienceDaily (Jan. 31, 2012) Testosterone makes us overvalue our own opinions at the expense of cooperation, research from the Wellcome Trust Centre for Neuroimaging at UCL (University College London) has found. The findings may have implications for how group decisions are affected by dominant individuals.
Problem solving in groups can provide benefits over individual decisions as we are able to share our information and expertise. However, there is a tension between cooperation and self-orientated behaviour: although groups might benefit from a collective intelligence, collaborating too closely can lead to an uncritical groupthink, ending in decisions that are bad for all.
Attempts to understand the biological mechanisms behind group decision making have tended to focus on the factors that promote cooperation, and research has shown that people given a boost of the hormone oxytocin tend to be cooperative. Now, in a study recently published in the journal Proceedings of the Royal Society B, researchers have shown that the hormone testosterone has the opposite effect -- it makes people act less cooperatively and more egocentrically.
Dr Nick Wright and colleagues at the Wellcome Trust Centre for Neuroimaging at UCL carried out a series of tests using 17 pairs of female volunteers* who had previously never met. The test took place over two days, spaced a week apart. On one of the days, both volunteers in each pair were given a testosterone supplement; on the other day, they were given a placebo.
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