A human’s self-awareness is controlled by a small region in the brain called the anterior insular cortex (insula). Within the insula lies a unique cell type – the von Economo neuron (VEN) – believed to be unique to humans, elephants, whales and great apes.

Now, German researchers have found that the VEN also occurs in the insula of macaque monkeys.

The very anterior part of the insula in particular is where humans consciously sense emotions, such as love, hate, resentment, self-confidence or embarrassment.

According to Henry Evrard, a neuroanatomist at the Max Planck Institute for Biological Cybernetics in Tübingen, Germany, the morphology, size and distribution of the monkey VEN indicates that it shares the same characteristics of the human VEN.

Findings from the study provide researchers with new opportunities to examine, in detail, the connections and functions that could play a vital role in human self-awareness, mental disorders including autism, as well as specific forms of dementia.

The insula is also involved in various psychopathologies, and damage of the insula results in apathy, as well as the inability to determine what feelings we or others we converse with experience.

According to the researchers, these inabilities and alteration of the insula are also found in autism, as well as in other highly detrimental neuropsychiatric disorders, such as the behavioral variant of frontotemporal dementia (bvFTD).

Evrard highlights that although the the macaque monkeys possess VEN they are unable to recognize themselves in a mirror, a behavioral characteristic of self-awareness.

Evrard explained:

“This means, other than previously believed, that highly concentrated VEN populations are not an exclusivity of hominids, but also occurs in other primate species.

Most importantly, the very much-needed analysis of the connections and physiology of these specific neurons is now possible.

Knowing the functions of the VEN and its connections to other regions of the brain in monkeys could give us clues on the evolution of the anatomical substrate of self-awareness in humans and may help us in better understanding serious necropsychiatric disabilities including autism, or even addictions such as to drugs or smoking.”

Written By Grace Rattue