Von Economo and fork neurons in the monkey insula, implications for evolution of cognition

The von Economo and fork neurons are atypical cortical projection neurons. They occur in insular and cingulate cortical areas that interface homeostatic bodily states with high-order brain functions. Their recent discovery in the macaque monkey offers a unique opportunity to examine the neurocellular basis of interoception in cognitive processes including perceptual awareness and perhaps language.