Septal region

Regio septalis

Septum, Nucleus septalis lateralis, Nucleus septalis medialis, Cell group Ch1 , Ch1 , Brain reward system

The septal region is considered the main "pleasure center" of the brain. Electrical stimulation of the septum in humans gives rise to an extraordinarily strong feeling of well-being. Laboratory animals with an implanted ability to "self-stimulate" (pedal-connected excitation electrode) their septal region are in some cases so completely occupied with stimulating themselves that they starve to death. The septal region, together with primarily the nucleus accumbens and area tegmentalis ventralis, is considered to be the brain's so-called reward system, which is of the greatest importance in connection with the development of a drug addiction.
If the septum is removed/destroyed on both sides, an extremely irritable condition arises, so-called septal rage.

The septal region is located rostral at the base of the septum pellucidum, slightly above Meynert's basal nucleus, and contains some small accumulations of grey matter: the so-called septal nuclei (nucleus septalis lateralis and nucleus septalis medialis).

The area is part of the basal forebrain and is connected to the amygdala via Broca's diagonal band, to the bulbus olfactorius via the inner olfactory streak, to the hippocampus complex via fornix and striae longitudinales and to the medial habenula nucleus via the stria medullaris thalami.

The nucleus septalis medialis contains cell group Ch1 that produces acetylcholine and together with cell group Ch2 "irrigates" the hippocampus with acetylcholine.
Septal neurons are thought to be responsible for the theta wave activity that the hippocampus exhibits when moving around in its environment.
Septum, in turn, is under the influence of a theta wave activity that emanates from nuclei in the wart body and has to do with the regulation of the individual's alertness, including the nucleus tuberomamillaris (histamine nucleus).