Do vagal afferents synapse at parasympathetic motor neurons within the brainstem?
The McDougall/Viscerosensory lab at the Florey Institute studies the basic neurophysiology underpinning the integration of sensory information within the brain. Our focus of study is at the level of the brain that first receives signals from visceral organs including those of the cardiorespiratory and gastrointestinal systems. This basic knowledge gained is pertinent to several disease states including; hypertension and obesity, and mental health. The primary techniques utilised within the laboratory revolve around anatomical mapping using viral tools in combination with in vitro slice electrophysiology. We possess a large skill-set and toolkit to answer a variety of experimental questions including optogenetics through to behavioural paradigms.
Background: Sensory signals from internal organs are organised and processed upon first entering the brain is ill defined. Viscerosensory signals arise from several functional modalities; baroreceptors, chemoreceptors, lung stretch afferents, gastrointestinal etc. These varied signals terminate in the solitary nucleus to initiate autonomic reflexes to change internal organ function.
Project: We have observed terminations in other brain regions too. Here you will use optogenetic tools and slice electrophysiology to determine if vagal afferents synapse at parasympathetic motor neurons. If so, this will redefine autonomic reflex circuitry as we know it.