Cognitive Tradeoff Hypothesis

The cognitive tradeoff hypothesis holds that in the cognitive evolution of humans, an evolutionary tradeoff occurred between short-term working memory and complex language skills, so that early hominids sacrificed the robust working memory still seen in chimpanzees in exchange for the more complex representations and hierarchical organization that language requires. The theory was first put forward by the Japanese primatologist Tetsuro Matsuzawa, a former director of the Primate Research Institute of Kyoto University, who suggests that at a certain point in evolution, limits on brain capacity meant the human brain may have acquired new functions in parallel with losing others, such as gaining language while losing visuospatial temporal storage ability.