Author response: Phylogenetic variation in cortical layer II immature neuron reservoir of mammals

Phylogenetic variation in cortical layer II immature neuron reservoir of mammals

The adult mammalian brain is mainly composed of mature neurons. A limited amount of stem cell-driven neurogenesis persists in postnatal life and is reduced in large-brained species. Another source of immature neurons in adult brains is cortical layer II. These cortical immature neurons (cINs) retain developmentally undifferentiated states in adulthood, though they are generated before birth. Here, the occurrence, distribution and cellular features of cINs were systematically studied in 12 diverse mammalian species spanning from small-lissencephalic to large-gyrencephalic brains. In spite of well-preserved morphological and molecular features, the distribution of cINs was highly heterogeneou…

Human brain evolution : how the increase of brain plasticity made us a cultural species

Why are humans so different from other primate species? What makes us so capable of creating language, art and music? The specializations in human brain anatomy that are responsible for our unique behavioral and cognitive traits evolved over a very short period of evolutionary time (between six and eight million years). Recent evidence suggests that, alongside a reorganization of the brain and an increase in its size, neural plasticity may also play a major role in explaining the evolutionary history of our species. Plasticity is the propensity of the brain to be molded by external influences, including the ecological, social and cultural context. The impact of these environmental influence…