A genetic signature for the neurons that control ingestion

Air breathing animals share a common passage for eating, drinking and breathing. This creates a precarious situation where solids and liquids can be mis-directed into the lungs during transfer from the mouth to the throat. This risk is further exacerbated in humans due to the unusually low position of the voice box, needed for production of complex speech. The swallowing movement that protects the airway during feeding is one of the most complex series of muscular contractions performed by the body, requiring the precisely timed contraction of roughly 26 pairs of muscles. These many moving parts render swallowing prone to failure, and such swallowing difficulties are common and devasting feature of many neurodegenerative diseases. While it is known that swallowing is a fully automatic behaviour, generated in the ancient medullary hindbrain, the specific neurons and neural connections responsible for its programming remain virtually unknown. This project will produce new insights into the genetic identity of these neurons and the connectivity schemes within the brain that orchestrate swallowing, improving our understanding of the neurobiology of feeding. Potential benefits include generating a new anatomical marker and genetic tools by which swallowing control centres can be identified and studied in the mammalian nervous system. Identifying these new swallowing brain regions and cell types will lead to a more complete understanding of the mechanisms that underpin the generation of the swallowing motor pattern and reveal potential candidates that underpin the failure of swallowing in dyspagia. This will have direct consequences in the refinement of education in the biological fields, most importanly anatomy and physiology, and provide cellular targets within the brain for future studies focused on drug development to address swallowing disorders in humans.