Amygdalofugal pathway
The amygdalofugal pathway and the stria terminalis together “ enable the corticomedial amygdala to directly control the medial hypothalamus and enable the basolateral amygdala to directly control the lateral hypothalamus and PAG,” or midbrain periaqueductal gray.
Through the bed nucleus of the stria terminalis, the amygdala additionally modulates the hypothalamus and PAG indirectly.
[11] The central nucleus can be thought of as the exit of the amygdaloid bodies through which the bodily responses that are associated with fear leave the amygdala.
It is the medial subnucleus that forms connections with “response control regions.” Most of the projection neurons in the central nucleus are inhibitory.
[13] The connections of the amygdalofugal pathway to the nucleus accumbens plays a role in the perception of a stimulus as either gratifying or aversive.
[13] After leaving the substantia innominata, the ventral amygdalofugal pathway continues on a medial path to enter the septal region, the lateral preoptic area, the hypothalamus, and the nucleus of the diagonal band.
The fibers which bypass the preoptic area and the hypothalamus travel more superiorly and enter the inferior thalamic peduncle.
Lesions to the dorsal medial nucleus cause amnesic syndromes, but they need to interrupt both the mammillothalamic tract and the amygdalofugal pathway in order to do so.
[21] The pyriform cortex and the basolateral nucleus are considered to be the main starting points of the amygdalofugal pathway.
[20][21] The connection from the basolateral nucleus that goes deep to the pyriform cortex is also considered part of the amygdalofugal pathway.
It has been implicated in a wide variety of cognitive functions as well as transient mood changes, depression and anxiety disorders, and the perception of pain.
These control body temperature, hunger, moods, sex drive, sleep, thirst, and release of other hormones.
The hypothalamus also influences daily physiologic cycles and plays a role in regulating emotional responses.
