[1] The septal nuclei receive reciprocal connections from the olfactory bulb, hippocampus, amygdala, hypothalamus, midbrain, habenula, cingulate gyrus, and thalamus.
In the 1950s, Olds & Milner showed that rats with electrodes implanted in this area will self-stimulate repeatedly (e.g., press a bar to receive electric current that stimulate the neurons).
Cells located in the intermediolateral septum also project through the lateral part of the fimbria to all CA fields of the ventral hippocampus and adjacent subicular and entorhinal cortices.
[13] In addition, cells located in the horizontal limb of the diagonal band project massively to the pars posterior of the medial mammillary nucleus, the ventral tegmental area, and amygdala.
[10] Inhibitory GABA, and excitatory glutamate, which regulate lateral septum (LS) activity, have been found to be increased during social play in juvenile rats.
Septal lesions significantly decreased serum LH and testosterone levels in male rats, while FSH and prolactin production were unaffected by the surgery.
Despite the diverse direct projection system between the hippocampus and the lateral septum, the first pieces of evidence regarding the role of latter brain area in memory formation and retention have only started to emerge as of 2022.
It is clear, that some role is being played, as oxytocin and vasopressin, when administered into the lateral septum after social training were able to enhance memory formation,[23][24] while their respective receptor blockers had the opposite effect.
Pieces of evidence suggesting the role the lateral septum could be playing in fear memory formation and consolidation have started emerging at the end of the XX.
[26] Inhibitory avoidance tasks using footshock chambers on mice were deployed to study the effects of the disruption of the lateral septum and hippocampal inputs on fear memory formation and retrieval respectively.