Decoding circuit neural activity in peripheral nerve and cerebral cortex with Optical Coherence Tomography of structure and birefringence

The supervisors work in an interdisciplinary neuroscience/engineering group whose
goal is to develop methods to image circuit activity over milliseconds in the peripheral
nerve and cerebral cortex. In the peripheral nerve, this occurs in compartments within
the nerve termed "fascicles". A current interest, funded by the National Institute of
Health, USA, lies in imaging activity in autonomic nerves which control internal organs
such as the heart and lungs, with a view to treating diseases such as epilepsy,
diabetes and arthritis by focused electrical stimulation from implanted microchip
devices. The function of such fascicles is not yet known; using electrophysiology, X-ray
microCT and Electrical Impedance Tomography (EIT), we have identified fascicles in
the cervical vagus nerve in the neck which supply the larynx, heart, lungs and
digestive system. We are collaborating with a group at Harvard/MGH who have
developed Optical Coherence Tomography (OCT) to trace connections between
fascicles and the organs they supply by high-resolution imaging of structure. This
project will be to utilize OCT with the other techniques to identify functional
connections. We will also extend OCT to image optical birefringence changes during
activity. Initial studies will be on the cervical vagus nerve in the anaesthetised pig and
humans. This will be extended to imaging in the brain and decoding of imaged
functional activity during physiological and pathological activity in nerve or epileptic
seizures in the brain. If successful, this would provide a groundbreaking new technique
able to image neural activity over milliseconds to a cellular level resolution of 10.