Brain Evolution

Emiliano Bruner, a paleoneurologist at the Centro Nacional de Investigacion sobre la Evolución Humana (CENIEH) has just published an opinion paper about self domestication and visuospatial cognition in the humans; which speculates on whether the two traits might have had reciprocal influences or shared mechanisms.

Parietal regions of brain

On the one hand, the hypothesis of self domestication proposes that the human being has undergone a process of juvenilization over the course of evolution to limit aggressiveness between individuals and promote cooperation in large social groups. On the other hand, our species presents an anatomical evolution in the parietal regions of the brain; so implicate in visuospatial integration, visual imagination and integration between body and environment.

The parietal cortex is involve in multiple association tasks; but is particularly crucial for visuospatial integration bridging body and vision; also coordinating eye and hand and is central to functions like visual imaging; so body center space and time simulation, and self-awareness.

Morphological changes in the modern human parietal cortex are not describe among early Homo sapienspopulations (say 100–300 thousand years ago); but are detect in later specimens, roughly at the time; so the archaeological record begins to show complex tools, projectile technology, and complex graphic culture.

The cerebral plasticity

Both aspects, in fact, are involve in technological ability and social complexity; so they depend on the patterns of our life stages (adolescence, longevity, etc.); also are relate with changes in the levels of cerebral plasticity. Reduce aggressiveness in a species is often obtaine by retaining juvenile traits, and these “domesticate bodies” then have a juvenile appearance; individuals are more highly social and evince greater plasticity at the level of behavior (exploration, curiosity, creativity).

The development of the parietal cortex influences the capacity to connect the body with technology; also increases the number of individuals with whom we can interact in the social group. It is to be expect, then, that these two aspects will have interact over the course of the evolution of the human genus; also above all in our speciesHomo sapiens, explains Bruner. The paper has been publish in the journal Frontiers in Psychology in a volume dedicate to self domestication and human evolution.

Some aspects of these evolutionary features are likely to have interact; so generating reciprocal enhancement. Others may hide common mechanisms, possibly due to ontogenetic communalities and shared developmental components. In this regard, one candidate may be neural plasticity, which is both a crucial consequence of paedomorphic conditions and a feature particularly influencing the development of the parietal cortex because of its sensitivity to sensorial inputs.