Ventromedial prefrontal cortex
Encyclopedia
The ventromedial prefrontal cortex is a part of the prefrontal cortex
Prefrontal cortex
The prefrontal cortex is the anterior part of the frontal lobes of the brain, lying in front of the motor and premotor areas.This brain region has been implicated in planning complex cognitive behaviors, personality expression, decision making and moderating correct social behavior...

 in the mammalian brain. The ventral medial prefrontal is located in the frontal lobe and is implicated in the processing of risk
Risk
Risk is the potential that a chosen action or activity will lead to a loss . The notion implies that a choice having an influence on the outcome exists . Potential losses themselves may also be called "risks"...

, fear
Fear
Fear is a distressing negative sensation induced by a perceived threat. It is a basic survival mechanism occurring in response to a specific stimulus, such as pain or the threat of danger...

, and in decision making
Decision making
Decision making can be regarded as the mental processes resulting in the selection of a course of action among several alternative scenarios. Every decision making process produces a final choice. The output can be an action or an opinion of choice.- Overview :Human performance in decision terms...

.

Anatomy

The ventromedial prefrontal cortex has been described as equivalent to Brodmann area 10
Brodmann area 10
Brodmann area 10, or BA10 is the frontopolar part of the frontal cortex in the human brain. BA10 was originally defined in terms of cytoarchitectonic traits in autopsy brains; modern functional imaging research cannot directly identify these boundaries and the terms anterior prefrontal, rostral...

. However, not all sources agree on the boundaries of the area.

To get a rough idea of where the ventromedial prefrontal cortex is, recall that the left and right hemispheres of the brain are separated (by the longitudinal cerebral fissure.) Now imagine you could take your hand and starting at the anterior brain (where your forehead is) insert it into this gap until you reached the insula
Insular cortex
In each hemisphere of the mammalian brain the insular cortex is a portion of the cerebral cortex folded deep within the lateral sulcus between the temporal lobe and the frontal lobe. The cortical area overlying it towards the lateral surface of the brain is the operculum...

 (a structure that is beneath the frontal lobe.) Your palm would be touching a part of the prefrontal cortex, which is in the front part of the brain and the lower part of your palm would be touching the ventral medial prefrontal cortex.

Note that different researchers use the term 'Ventromedial prefrontal cortex' differently. Sometimes, the term is saved for the area above the medial orbitofrontal cortex
Orbitofrontal cortex
The orbitofrontal cortex is a prefrontal cortex region in the frontal lobes in the brain which is involved in the cognitive processing of decision-making...

, while at other times, 'ventromedial prefrontal cortex' is used to describe a broad area in the lower (ventral) central (medial) region of the prefrontal cortex, of which the medial orbitofrontal cortex
Orbitofrontal cortex
The orbitofrontal cortex is a prefrontal cortex region in the frontal lobes in the brain which is involved in the cognitive processing of decision-making...

 constitutes the lower-most part. This latter, broader area corresponds to the area damaged in patients with decision-making impairments investigated by António Damásio
Antonio Damasio
Antonio Damasio is David Dornsife Professor of Neuroscience at the University of Southern California, where he heads USC's Brain and Creativity Institute and Adjunct Professor at the Salk Institute. Prior to taking up his posts at USC, in 2005, Damasio was M.W...

 and colleagues (see diagram, and below).

Function

As of yet, functional differences between the orbitofrontal and ventromedial areas of the pre-frontal cortex are not clearly established, although the areas of the ventromedial cortex superior to the orbitofrontal cortex
Orbitofrontal cortex
The orbitofrontal cortex is a prefrontal cortex region in the frontal lobes in the brain which is involved in the cognitive processing of decision-making...

 are much less associated with social functions and more with pure emotion regulation. Research in developmental neuroscience also suggested that neural networks in the ventromedial prefrontal cortex are rapidly developing during adolescence and young adulthood supporting emotion regulation through the amygdala, being associated with a decrease in cortisol
Cortisol
Cortisol is a steroid hormone, more specifically a glucocorticoid, produced by the adrenal gland. It is released in response to stress and a low level of blood glucocorticoids. Its primary functions are to increase blood sugar through gluconeogenesis; suppress the immune system; and aid in fat,...

 levels.

Left lateral and medial orbitofrontal cortex
Orbitofrontal cortex
The orbitofrontal cortex is a prefrontal cortex region in the frontal lobes in the brain which is involved in the cognitive processing of decision-making...

 areas were also measured to be highly active during guessing tasks. An increase in probabilistic scenario complexity was associated with orbitofrontal cortex
Orbitofrontal cortex
The orbitofrontal cortex is a prefrontal cortex region in the frontal lobes in the brain which is involved in the cognitive processing of decision-making...

 activity level increase, therefore suggesting the special role that the ventromedial prefrontal cortex plays in decision making containing uncertainty. A study also indicated that patients with lesions in the ventromedial prefrontal cortex tend to have difficulties reacting to future consequences.

The right half of the ventromedial prefrontal cortex was associated with regulating the interaction of cognition and affect in the production of empathic responses. Hedonic (pleasure) responses were also associations to orbitofrontal cortex
Orbitofrontal cortex
The orbitofrontal cortex is a prefrontal cortex region in the frontal lobes in the brain which is involved in the cognitive processing of decision-making...

 activity level by Morten Kringelbach. This finding contributes findings suggesting ventromedial prefrontal cortex being associated with preference judgement, possibly assigning the ventromedial prefrontal cortex a key role in constructing one's self. Studies with PTSD also supported the idea that the ventromedial prefrontal cortex is an important component for reactivating past emotional associations and events, therefore essentially mediating pathogenesis of PTSD. Treatments geared to the inhibition of the ventromedial prefrontal cortex were therefore suggested for PTSD. The right half of the ventrolateral prefrontal cortex, being active during emotion regulation, was activated when participants were offered an unfair offer in a scenario. Specific deficits in reversal learning and decision-making have led to the hypothesis that the ventromedial prefrontal cortex is a major locus of dysfunction in the mild stages of the behavioural variant of frontotemporal dementia
Frontotemporal dementia
Frontotemporal dementia is a clinical syndrome caused by degeneration of the frontal lobe of the brain and may extend back to the temporal lobe...

.

One particularly notable theory of VMPFC function is the somatic marker hypothesis, accredited to António Damásio
Antonio Damasio
Antonio Damasio is David Dornsife Professor of Neuroscience at the University of Southern California, where he heads USC's Brain and Creativity Institute and Adjunct Professor at the Salk Institute. Prior to taking up his posts at USC, in 2005, Damasio was M.W...

. By this hypothesis, the VMPFC has a central role in adapting somatic markers - emotional associations, or associations between mental objects and visceral (bodily) feedback - for use in natural decision making. This account also gives the VMPFC a role in moderating emotions and emotional reactions.

Ventromedial prefrontal cortex lesions were also associated with a deficit in processing gender specific social cues.

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