The anterior cingulate cortex. The evolution of an interface between emotion and cognition.

TLDR

The anterior cingulate cortex integrates emotional self‑control, focused problem solving, error detection, and adaptive responses, key functions of intelligent behavior. The study proposes that the ACC is a neocortical specialization, not a primitive cortical stage. Evidence from single‑neuron recordings, electrical stimulation, EEG, PET, fMRI, and lesion studies supports the ACC’s role in these functions. The ACC contains spindle‑shaped neurons unique to humans and great apes that are widely connected, emerge postnatally, and whose survival is modulated by enrichment or stress, suggesting a role in coordinating problem‑solving and emotional self‑control.

Abstract

We propose that the anterior cingulate cortex is a specialization of neocortex rather than a more primitive stage of cortical evolution. Functions central to intelligent behavior, that is, emotional self-control, focused problem solving, error recognition, and adaptive response to changing conditions, are juxtaposed with the emotions in this structure. Evidence of an important role for the anterior cingulate cortex in these functions has accumulated through single-neuron recording, electrical stimulation, EEG, PET, fMRI, and lesion studies. The anterior cingulate cortex contains a class of spindle-shaped neurons that are found only in humans and the great apes, and thus are a recent evolutionary specialization probably related to these functions. The spindle cells appear to be widely connected with diverse parts of the brain and may have a role in the coordination that would be essential in developing the capacity to focus on difficult problems. Furthermore, they emerge postnatally and their survival may be enhanced or reduced by environmental conditions of enrichment or stress, thus potentially influencing adult competence or dysfunction in emotional self-control and problem-solving capacity.