Max Planck scientists discover brain cells in monkeys that may be linked to self-awareness and empathy in humans
The anterior insular cortex is a small brain region that plays a crucial role in human self-awareness and in related neuropsychiatric disorders. A unique cell type – the von Economo neuron (VEN) – is located there. For a long time, the VEN was assumed to be unique to humans, great apes, whales and elephants. Henry Evrard, neuroanatomist at the Max Planck Institute for Biological Cybernetics in Tübingen, Germany, now discovered that the VEN occurs also in the insula of macaque monkeys. The morphology, size and distribution of the monkey VEN suggest that it is at least a primal anatomical homolog of the human VEN. This finding offers new and much-needed opportunities to examine in detail the connections and functions of a cell and brain region that could have a key role in human self-awareness and in mental disorders including autism and specific forms of dementia.
The insular cortex, or simply insula, is a hidden cortical region folded and tucked away deep in the brain – an island within the cortex. Within the last decade, the insula has emerged from darkness as having a key role in diverse functions usually linked to our internal bodily states, to our emotions, to our self-awareness, and to our social interactions. The very anterior part of the insula in particular is where humans consciously sense subjective emotions, such as love, hate, resentment, self-confidence or embarrassment. In relation to these feelings, the anterior insula is involved in various psychopathologies. Damage of the insula leads to apathy, and to the inability to tell what feelings we or our conversational partner experience. These inabilities and alteration of the insula are also encountered in autism and other highly detrimental neuropsychiatric disorders including the behavioural variant of frontotemporal dementia (bvFTD).