Hagmann et al, Creative Commons 2.5, Plos Biology
As part of a series on the Brodmann Areas, this is a brief overview of some of the literature on Brodmann Area 25 – the Anterior Cingulate Cortex (ACC). The ACC is functionally and anatomically closely related to the Insular Cortex (see also reviews below on the Insular Cortex). The ACC contains a special type of cell called the Von Economo Neuron (see this review article). These cells also found in the Insular Cortex and are massively interconnected with cells throughout the brain and although present in other primates are significantly more abundant in humans (although obviously brain volume is correspondingly increased in humans). The ACC has been associated with psychophysiological functions including empathy, salience networks, performance on reward related tasks, creativity and insight, meditation, risk assessment, brain-gut interactions, empathy for pain, the umami taste, interoception (along with the insular cortex) which is related to a number of the above functions, switching from automatic to controlled behaviours, and the placebo response. In pathology, the ACC has been associated with depression, dyspnoea, irritable bowel syndrome, pain, psychosis (and more specifically schizophrenia), autism, substance misuse, panic disorder (see also this review article), borderline personality disorder, obsessive-compulsive disorder, anorexia, Tourette Syndrome, Fragile X syndrome and also with antisocial traits, The association with depression has been investigated in relation to social rejection. The reader may be impressed by the vast array of important physiological and pathophysiological associations of the ACC and there are two obvious implications. The first is that the ACC is a structure of profound biological importance and one which plays a role in many illness conditions as outlined above. The other possibility is that given the interconnectivity of the ACC (possibly due to the Von Economo Neurons) it is active during many brain processes covering a variety of activities. In other words it may form a part of multiple brain networks distinguishing it from most other brain regions. Here the ACC can be conceptualised as a centre for transmitting interoceptive information to other brain regions for further processing. The research above as well as other studies in the field present a challenging question of just what the role of the ACC is and how it can be associated with so many different phenomenon.
Appendix – Articles Reviewed in relation to Brodmann Areas or other Structures
Brodmann Area 1 – Somatosensory Cortex
Brodmann Area 2 – The Primary Motor Cortex
Brodmann Area 6 (Agranular Frontal Area 6)
Brodmann Areas 13 and 14 (Insular Cortex)
Brodmann Area 15 (Anterior Temporal Lobe – Controversial Area in Humans)
Brodmann Area 27 (Piriform Cortex)
Brodmann Area 28 (Entorhinal Cortex)
Brodmann Areas 45, 46, 47 (Inferior Frontal Gyrus)
Medial Temporal Lobe
Miscellaneous Subcortical Structures
Generic Articles Relating to Localisation
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