Neuroimaging, neurophysiological and neuroimmune correlates of Vagus Nerve modulation in schizophrenia: An Investigative tVNS study (2020-Present)
Scientific Abstract: Aetiopathological research in schizophrenia reveal autonomic, inflammatory and attentional dysfunction. The vagus nerve may be a common link between these. Recent advances have enabled safe and feasible trans-auricular stimulation of the vagus nerve. We plan to assess the autonomic function through heart-rate variability and pupil dilation, inflammatory system by blood inflammatory markers such as interleukins (IL-1beta and IL-6) and their epigenetics (promoter regions of IL-1beta and IL-6), and attention (exteroception and interoception) through evoked response potentials (P300), auditory steady state response (gamma oscillations) and heartbeat evoked potentials. We will evaluate the changes in these parameters before and after a single session of trans-auricular vagus nerve stimulation and compare these between healthy controls and those with schizophrenia.
Layman Brief: We understand the outside world through our sense organs like eyes, ears, nose etc, which relay such signals to the brain. However, the brain also receives many different signals from within our body. These maybe simple things like the heartbeat, hunger, need to go to the toilet, feeling feverish and sleepiness, to complex issues like our intuition, “gut feeling”, mood fluctuations and identity of self. Where do these signals come from, who carries them, who interprets them and who regulates them? Moreover, many of these are disturbed in those who suffer from mental disorders, especially from schizophrenia. One ideal candidate which can answer these questions is our vagal nerve. It is the longest nerve in our body and serves various related functions. However, stimulating the nerve is difficult as it is inside our body. Luckily, a part of the nerve is present in our ears and new methods have emerged by which we can stimulate a portion of our ears and thereby stimulate the vagus nerve, without even pricking the ear. We plan to understand what happens when the vagus nerve is stimulated and we plan to use various scientific modalities like our eye movements, brain waves, heart rates, and blood tests to evaluate these. We plan to study these in healthy people and those who suffer from schizophrenia.
PhD Scholar: Dr. Swarnabuddha Nayok
Supervisor: Prof. Venkatasubramanian G.
Funding: Indian Council of Medical Research (ICMR) & DBT-Wellcome Trust India Alliance funded Clinical Research Centre for Neuromodulation in Psychiatry (Ref:IA/CRC/19/1/610005)