Theregions of the brain where odors are processed-the temporal lobe and the olfactory bulb- was larger in the firsthomo sapiensthat in those ofHomo neanderthalensis, according to an investigation led by the Higher Council for Scientific Research (CSIC) and published in the journalNature Communications.
Using 3D morphometric analysis, the research authors have measured the impressions left by the brain at the inner base of the skull. In this way they have come to the conclusion thatthe structure that receives the olfactory information is approximately 12% greater in H. sapiens. Likewise, the size of the temporal lobes, related to language, memory and social functions, is also higher in modern man.
? The increase in the size of the brain is closely linked to the evolution of humanity ?, explains Markus Bastir, researcher at the CSIC at the National Museum of Natural Sciences and responsible for the work. Although sapiens and Neanderthals belong to two different evolutionary lineages, they both have large and similarly sized brains. Therefore, “the analysis of brain shape could reflect differences in its evolutionary reorganization”, adds Bastir.
The olfactory information is projected to brain regions directly responsible for the processing of emotions, motivation, fear, memory, pleasure and attraction between people. In fact,higher olfactory functions are those that combine smell and cognitive processessuch as perception, motivation, intuition, judgment and decision making. “The fact that theH. sapienshas olfactory bulbs larger than any other human species, it could indicate a greater and different sense of smell, possibly involved in the development of aspects related to social functions “, suggests Antonio Rosas, co-author of the work. These differences could make evolutionary sense in a context social and contribute to the recognition of individuals in the group, cohesion and social learning.
Smell is the oldest vertebrate sense and the only channel through which the brain connects directly to the environment. Furthermore, according to Rosas, “he never sleeps because the body always breathes.” The neural circuit of smell is closely linked to the neurological material of memory and emotions, and this explains the enormous emotional intensity that is experienced when remembering any experience associated with smell.
