Edited by: Erika Gyengesi, Western Sydney University, Australia
This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
The medial septum (MS) has long been studied for its role in the generation of hippocampal theta oscillation, the dominant rhythm of the limbic system during information collecting behaviors and REM sleep (Buzsáki,
Exploration of medial septum's involvement in motivated behaviors predates the discovery of its role in hippocampal oscillogenesis. However, following the report of rhythmic bursting medial septal neurons coupled to theta activity in the hippocampus, the main focus shifted to studying how medial septum controls memory-related physiological phenomena. The review by
Glutamatergic MS neurons were shown to potently control locomotive behavior in mice; however, MS cholinergic and GABAergic neurons also show correlations with locomotion, indicating complex MS functions related to animal speed. In an original research article,
MS neurons process motion, reinforcement, memory and attentional information, prompting an update on how the MS participates in mnemonic processing.
As noted, the MS orchestrates hippocampal theta oscillations related to learning, memory, and spatial navigation, but also to anxiety and fear in the ventral hippocampus. Additionally, oscillatory control by the MS may go beyond the theta frequency band, and physiological rhythms affected by the MS are often disrupted in pathological conditions.
Network mechanisms whereby sensory inputs are transformed into the rhythmic output of the medial septum are still largely unknown. The original research by
Recent landmark discoveries unraveled fundamental mechanisms of social memory formation. The medial septum is thought to be a key coordinator of the episodic memory circuit; thus, linking its already known functions with new findings about social learning is the key objective of
We live in exciting times. The methodological revolution of neuroscience research has uncovered countless novel findings and put old discoveries into new light. The medial septum has long been known as a key center for rhythm genesis. Despite decades of research, it remained an enigmatic region holding its secrets tight to its chest. Nonetheless, novel methods enabled cracking many unknown aspects of medial septal functions. Authors of this collection of papers highlighted many new discoveries and placed them into the context of what we already know about the medial septum. Furthermore, connecting basic discoveries with clinical findings raised the intriguing possibility that this region, through its many connections, is in an ideal position whereby lost coordination of activity can be restored. Thus, many new directions of medial septum research may emanate from both long-known facts and new findings, a large part described in this article collection.
BH and VV wrote the editorial. All authors contributed to the article and approved the submitted version.
This work was supported by the NAP3.0 National Program of the Hungarian Academy of Sciences, NKFIH K135561, SPIRITS 2020 of Kyoto University, and the European Research Council Starting Grant no. 715043 to BH and NKFIH K132735 to VV.
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.