Cerebral cortex and hippocampus neural interaction during vagus nerve stimulation under in vivo large-scale imaging

Abstract

ObjectiveThe purpose of this study was to study mechanisms of VNS modulation from a single neuron perspective utilizing a practical observation platform with single neuron resolution and widefield, real-time imaging coupled with an animal model simultaneously exposing the cerebral cortex and the hippocampus.MethodsWe utilized the observation platform characterized of widefield of view, real-time imaging, and high spatiotemporal resolution to obtain the neuronal activities in the cerebral cortex and the hippocampus during VNS in awake states and under anesthesia.ResultsSome neurons in the hippocampus were tightly related to VNS modulation, and varied types of neurons showed distinct responses to VNS modulation.ConclusionWe utilized such an observation platform coupled with a novel animal model to obtain more information on neuron activities in the cerebral cortex and the hippocampus, providing an effective method to further study the mechanisms of therapeutic effects modulated by VNS.

The gut-brain vagal axis scales hippocampal memory processes and plasticity

“…Seminal articles have already shown that electrical stimulation of the whole vagus nerve (cervical level) improves learning and memory functions in both humans and rodents (Clark et al, 1999, 1998; Olsen et al, 2022; Peña et al, 2014; Sanders et al, 2019) by potentially activating the hippocampus (Xu et al, 2023) and/or by promoting hippocampal neurogenesis and plasticity-associated features (Biggio et al, 2009; Follesa et al, 2007; Olsen et al, 2022; Sanders et al, 2019). In addition, more recent studies have highlighted a clear impact of specific gut-brain vagal manipulations (selective ablations) onto hippocampal functions (O’Leary et al, 2018; Suarez et al, 2018), thus indicating that the gut represents, at least in part, a major peripheral organ with a strong vagus-mediated action onto learning and memory dynamics.…”