The infralimbic cortex (IL) is a cortical region in the
ventromedial prefrontal cortex
The ventromedial prefrontal cortex (vmPFC) is a part of the prefrontal cortex
in the mammalian brain. The ventral medial prefrontal is located in the frontal lobe at the bottom of the cerebral hemispheres and is implicated in the processing of r ...
which is important in tonic inhibition of subcortical structures and emotional responses, such as fear.
Structure
Connectivity
Primates
GABAergic
In molecular biology and physiology, something is GABAergic or GABAnergic if it pertains to or affects the neurotransmitter GABA. For example, a synapse is GABAergic if it uses GABA as its neurotransmitter, and a GABAergic neuron produces GABA. A ...
neurons within the
amygdala
The amygdala (; plural: amygdalae or amygdalas; also '; Latin from Greek, , ', 'almond', 'tonsil') is one of two almond-shaped clusters of nuclei located deep and medially within the temporal lobes of the brain's cerebrum in complex verteb ...
, known as
intercalated (ITC) cells, receive a strong projection from the IL
medial prefrontal cortex
In mammalian brain anatomy, the prefrontal cortex (PFC) covers the front part of the frontal lobe of the cerebral cortex. The PFC contains the Brodmann areas BA8, BA9, BA10, BA11, BA12, BA13, BA14, BA24, BA25, BA32, BA44, BA45, BA46, ...
(mPFC) in primates. ITC cells are thought to play a role as the 'off switch' for the amygdala, inhibiting the amygdala's central nucleus output neurons and its basolateral nucleus neurons.
[Quirk, G.J. & Mueller, D. (2007). Neural mechanisms of extinction learning and retrieval. Neuropsychopharmacology Reviews, 1-17.] Further, it has been shown that electrical stimulation of IL reduces conditioned fear and strengthens extinction memory, explaining cortical control over
extinction
Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...
processes, one of the simplest forms of
emotional regulation
Emotional self-regulation
or emotion regulation is the ability to respond to the ongoing demands of experience with the range of emotions in a manner that is socially tolerable and sufficiently flexible to permit spontaneous reactions as well as ...
.
Rodents
Amygdala ITC cells receive strong projection from the IL mPFC in rodents as well.
[McDonald et al., 1996.]
See also
*
Medial prefrontal cortex
In mammalian brain anatomy, the prefrontal cortex (PFC) covers the front part of the frontal lobe of the cerebral cortex. The PFC contains the Brodmann areas BA8, BA9, BA10, BA11, BA12, BA13, BA14, BA24, BA25, BA32, BA44, BA45, BA46, ...
*
Intercalated cells of the amygdala The intercalated cells of the amygdala (ITC or ICC) are a group of GABAergic neurons situated between the basolateral and central nuclei of the amygdala that play a significant role in inhibitory control over the amygdala. They play important regula ...
References
{{DEFAULTSORT:Infralimbic Cortex
Cerebral cortex