The Diagonal Band of Broca Regulates Olfactory-mediated Social Behaviors: A Study Using USVs As Unbiased, Ethological Markers For Social Interactions
1 IEECR
2 DZNE
Sensory perception is modulated in a top-down fashion by higher brain regions to regulate the strength of its own input resulting in the adaptation of behavioral responses. In olfactory perception, the Horizontal Diagonal Band of Broca (HDB), embedded in the basal forebrain modulates olfactory information processing by recruiting Olfactory Bulb (OB) interneurons to shape excitatory OB output. Currently, little is known about how specific HDB to OB top-down signaling affects complex olfactory-mediated behaviors. Here we show that the olfactory bulb is strongly and differentially innervated by HDB projections. Light-induced silencing of HDB afferents in OB via OPN3 affected olfactory-mediated social habituation and discrimination behaviors shown by manual annotation of investigative behavior. To support these findings we used ultrasonic vocalizations (USVs) as an unbiased, reliable, and thologically relevant biomarker for the quantification of social interactions. To this end we developed DeepFisFis an AI-based algorithm for real-time detection of mouse USVs. Collectively our studies show that USVs serve as an effective biomarker for affiliative behaviors and identified the HDB as a central top-down pathway for olfactory-mediated social abituation and discrimination behaviors.