PhD Scientific Days 2024

Poster Session I - Neurosciences 2.

A novel pathway: the corticopetal basal forebrain somatostatin neurons

Text of the abstract

The mammalian basal forebrain (BF) cholinergic, glutamatergic and GABAergic parvalbumin neurons target cortical areas, control its rhythmic activity, and has an important role in attention, motivation, learning and memory. The RSC is thought to play an important role in the integration of cognitive processes and it controls spatial navigation, contextual memory encoding and retrieval. Here, we discovered a previously unrecognised, long-range GABAergic, somatostatin-expressing (SOM) neuron population in the BF, which targets the retrosplenial cortex (RSC). Immunohistochemistry and confocal laser scanning microscopy in transgenic mice revealed that BF SOM neurons are GABAergic and target the somata and dendrites of parvalbumin-, somatostatin- and calretinin-expressing GABAergic interneurons in the RSC. Using retrograde viral tract tracing and fibrephotometry, we found that the RSC-projecting BF SOM neurons are active during both negative and positive stimuli. Our results so far suggest that BF SOM neurons have a role in encoding valence and broadcasting it to the RSC by disinhibiting selected subpopulations of principal neurons.

This work was supported by the New National Excellence Program of the Ministry of Innovation, Hungary: ÚNKP-23-3-I-SE-48.