Infralimbic cortex is a cortical region in the ventromedial prefrontal cortex

Ventromedial prefrontal cortex

The ventromedial prefrontal cortex is a part of the prefrontal cortex in the mammalian brain. The ventral medial prefrontal is located in the frontal lobe and is implicated in the processing of risk, fear, and in decision making.- Anatomy :...

 which is important in tonic inhibition of subcortical structures and emotional responses, such as fear.

Primates

GABAergic neurons within the amygdala

Amygdala

The ' are almond-shaped groups of nuclei located deep within the medial temporal lobes of the brain in complex vertebrates, including humans. Shown in research to perform a primary role in the processing and memory of emotional reactions, the amygdalae are considered part of the limbic system.-...

, known as intercalated (ITC) cells, receive a strong projection from the IL 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. Further, it has been shown that electrical stimulation of IL reduces conditioned fear and strengthens extinction memory, explaining cortical control over extinction

Extinction

In biology and ecology, extinction is the end of an organism or of a group of organisms , normally 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 recover may have been lost before this point...

 processes, one of the simplest forms of emotional regulation.