World Library  
Flag as Inappropriate
Email this Article

Septal nuclei

Article Id: WHEBN0003464816
Reproduction Date:

Title: Septal nuclei  
Author: World Heritage Encyclopedia
Language: English
Subject: Medial septal nucleus, Stria medullaris of thalamus, Edinger–Westphal nucleus, Fornix (neuroanatomy), Terminal nerve
Collection: Cerebrum, Limbic System, Neuroanatomy
Publisher: World Heritage Encyclopedia

Septal nuclei

Septal area
Latin nuclei septales
NeuroNames hier-241
Anatomical terms of neuroanatomy

The septal nuclei (medial olfactory area) are a set of structures that lie below the rostrum of the corpus callosum, anterior to the lamina terminalis (the layer of gray matter in the brain connecting the optic chiasma and the anterior commissure where the latter becomes continuous with the rostral lamina). The septal nuclei are composed of medium-size neurons which are classified into medial, lateral, and posterior groups. The septal nuclei receive reciprocal connections from the olfactory bulb, hippocampus, amygdala, hypothalamus, midbrain, habenula, cingulate gyrus, and thalamus. The septal area (medial olfactory area) has no relation to the sense of smell, but it is considered a pleasure zone in animals. The septal nuclei play a role in reward and reinforcement along with the nucleus accumbens. In the 1950s, Olds & Milner showed that rats with electrodes implanted in this area will self-stimulate repeatedly (i.e. press a bar to receive electrical current that will stimulate the neurons).[1] Experiments on the septal area of man have taken place since the 1960's.[2][3][4][5]

Connections with other structures

The dorsal septum projects to the lateral preoptic area, lateral hypothalamus, periventricular hypothalamus and midline thalamus.

Fibers from the ventral half of the septum project topographically to the hippocampal formation, thalamus, hypothalamus and midbrain. Specifically, neurons located along the midline in the vertical limb of the diagonal band of Broca project through the dorsal fornix to all CA fields of the dorsal hippocampus and adjacent subicular cortex. Other fibers from this region project through the stria medullaris to the medial and lateral habenular nuclei, the paratenial and anteromedial nucleus of the thalamus, and through the medial forebrain bundle to the pars posterior of the medial mammillary nucleus.

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. These cells also send fibers through the stria medullaris to the lateral habenular nucleus and mediodorsal thalamic nucleus. Other axons arising from these cells descend through the medial forebrain bundle to terminate in a region dorsal to the interpeduncular nucleus.

The lateral septum is a relay center for connections from the CA3 of the hippocampus to the ventral tegmental area. These connections help link reward signals with the context in which they occur.[6]

Fibers from the most lateral part of the ventral septum (i.e., bed nucleus of the anterior commissure) project through the stria terminalis to the ventral subiculum. 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.


  1. ^ Olds, J; Milner, P (December 1954). "Positive reinforcement produced by electrical stimulation of septal area and other regions of rat brain.". Journal of comparative and physiological psychology 47 (6): 419–27.  
  2. ^ Heath, R.G. (December 1, 1963) Electrical self-stimulation of the brain in man. American Journal of Psychiatry 120: 571-577.
  3. ^ 3: 23-30.Journal of Behavior Therapy and Experimental PsychiatryMoan, C.E., & Heath, R.G. (1972) Septal stimulation for the initiation of heterosexual activity in a homosexual male.
  4. ^ "Controversial Surgery for Addiction Burns Away Brain’s Pleasure Center" Author Maia Szalavitz. Dec. 13, 2012
  5. ^ "China Bans Irreversible Brain Procedure" Author Zamiska Nicholas. April 28, 2008. The Wall Street Journal
  6. ^ Luo, A. H.; Tahsili-Fahadan, P.; Wise, R. A.; Lupica, C. R.; Aston-Jones, G. (14 July 2011). "Linking Context with Reward: A Functional Circuit from Hippocampal CA3 to Ventral Tegmental Area". Science 333 (6040): 353–357.  
  • Neuroanatomy book of mansoura faculty of medicine (Egypt)

External links

  • Stained brain slice images which include the "septal%20nuclei" at the BrainMaps project
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.