Anterior cingulate cortex

The anterior cingulate cortex (ACC), previously known as the precingulate, is a region of the brain surrounding the anterior corpus callosum. It is involved in the limbic system and the prefrontal cortex.

Summary

• location: it is located superior to the anterior corpus callosum, more specifically Brodmann's areas 24, 25, 32, 33
• blood supply: it receives its vascular supply from the pericallosal artery
• relations: anterior part of the cingulate gyrus, involved in the limbic system and prefrontal cortex

Gross anatomy

Location

The anterior cingulate cortex forms the anterior part of the cingulate gyrus. It involves Brodmann's areas 24, 25, 32 and 33. The dorsal aspect of the anterior cingulate cortex has been separated and is now referred to as the middle cingulate cortex. It is predominantly located in the frontal lobe.

Relations

The anterior cingulate cortex is known to have extensive connections with the amygdala, the lateral hypothalamus and brainstem nuclei, hippocampal centers, orbitofrontal cortex and the ventral striatum.

Functions

The functions of the anterior cingulate cortex are only starting to be studied extensively due to its involvement in various mental health illnesses. The anterior cingulate cortex is involved in emotional regulation, emotion-based learning, discerning the impact of pain on emotion (via the amygdala), autonomic regulation (via the brainstem nuclei), memory (via the hippocampus) and the reward pathway (via the orbitofrontal cortex).

The activation of anterior cingulate cortex leads to a suppression of the limbic-system response leading to better emotional regulation.

Reduced activation of the anterior cingulate cortex leads to poor emotional regulation, as observed in patients with post-traumatic stress disorder, where there is an increased stress response to a previous traumatic memory or trigger. This is in contrast to social anxiety, there the region shows increased activation.

Patients with depression and schizophrenia also demonstrate the low activity of the anterior cingulate cortex, leading to a blunted affect ¹.

Blood supply

The anterior cingulate cortex, being part of the cingulate gyrus is supplied by the pericallosal arteries, which are branches of the anterior cerebral artery ².

Related pathology

• schizophrenia
• major depressive disorder