A Computational Model of Oxytocin Modulation of Olfactory Recognition Memory

Abstract

Social recognition in mammals depends on complex interactions between sensory and other brain areas as well as modulatory inputs by specific neuropeptides such as oxytocin (OXT). Social recognition memory specifically has been shown to depend among others on olfactory processing, and can be probed using methods similar to those used when probing non-social odor memory. We here use a computational model of two interconnected olfactory networks in the mouse, the olfactory bulb (OB) and anterior olfactory nucleus, to propose a mechanism for olfactory short-term recognition memory and its modulation in social situations. Based on previous experiments, we propose one early locus for memory to be the OB. During social encounters in mice, pyramidal cells in the anterior olfactory nucleus, themselves driven by olfactory input, are rendered more excitable by OXT release, resulting in stronger feedback to OB local interneurons. This additional input to the OB creates stronger dynamics and improves signal-to-noise ratio of odor responses in the OB proper. As a consequence, mouse social olfactory memories are more strongly encoded and their duration is modulated.

Genetic influences of autism candidate genes on circuit wiring and olfactory decoding

“…Higher-order areas, such as the ventral hippocampus, exhibit direct projections to the AON, whereby top-down input by the hippocampus on AON modulates the processing of incoming olfactory information, especially in regard to contextual processing and stored internal representations (Aqrabawi and Kim 2018;Levinson et al 2020). In this manner, the AON may act as a central hub between olfactory input and odor memory (Oettl et al 2016;Linster and Kelsch 2019;Aqrabawi and Kim 2020). To this effect, the AON is necessary for the expression of behavior relevant to the social odor memory.…”

Oxytocinergic Feedback Circuitries: An Anatomical Basis for Neuromodulation of Social Behaviors

“…The current leading hypothesis to explain OT effects on social behavior is that the neuropeptide selectively increases the saliency of socially relevant stimuli in areas enriched with OTR-expressing neurons (Shamay-Tsoory and Abu-Akel, 2015 ; Marlin and Froemke, 2016 ). This hypothesis is mainly based on results obtained in studies of the auditory and olfactory centers, where OT modulation acts on the excitation/inhibition balance of sensory circuits to increase the signal to noise ratio in favor of social stimuli and by this mechanism filter out less relevant stimuli (Marlin et al, 2015 ; Oettl et al, 2016 ; Linster and Kelsch, 2019 ). Although it is becoming clearer how OT may affect sensory systems, the mechanisms underlying targeted axonal release of OT in the socially relevant brain regions remain elusive.…”

Biological underpinnings for lifelong learning machines

“…These inputs likely provide the dynamic flexibility associated with task learning, reward association and appropriate motor response 98,99 . They allow for faster learning of new stimuli and gating of responses, including different responses to the same stimulus and stable responses in different environments 90,100,101 .…”