Neuroimaging and Neuromodulation of medial prefrontal connectivity in schizophrenia: An interventional psychiatry research using tACS and TMS-EEG (2021-Present)

​Scientific Brief: Medial prefrontal cortex (mPFC) is a major hub of default mode network and self-related networks. Literature suggests structural and functional mPFC connectivity abnormalities in schizophrenia. Current study attempts at evaluating role of mPFC in schizophrenia with a multipronged approach: cross-sectional evaluation of anatomical and functional connectivity abnormalities using neuroimaging. To understand the causal role, tACS will be used to modulate the connectivity of mPFC. The outcome of this modulation on biological markers of TMS-EEG & fMRI based cortical as well as clinical symptoms will be assessed.

​Layman Brief: Brain has an amazing array of communication network. One of the ways brain regions communicates is through brain waves or neural oscillations. The strength, frequency and duration of these electrical brain waves serve as the codes of these languages. Faulty network with faulty communication systems is known to be a reason behind schizophrenia. Transcranial alternating current stimulation (tACS) is a new treatment technique where weak intensity AC current is used. When applied at specific frequencies, these external electrical waves resonating with those of intrinsic brain wave can strengthen the communication and the communication network. tACS has shown some preliminary evidence to help reducing symptoms in patients with schizophrenia by improving these brain waves and communication networks. Specifically, a region called medial prefrontal cortex in the midline of brain deep inside the forehead is thought to be a hub of many communication networks in the brain. There seems to be a disruption in its connectivity with multiple other brain regions. We are trying to assess the anatomical and functional abnormalities of this brain region, as well as abnormalities in its connection with other brain regions. We are employing multimodal brain imaging techniques using magnetic resonance imaging (MRI) and electroencephalography (EEG) combined with its response to transcranial magnetic
pulses (TMS-EEG) to understand these abnormalities. We will be administering tACS in patients with schizophrenia for 5-10 days to see if true tACS indeed has ability to improve the symptoms of schizophrenia over and above a sham-tACS. We will also be
observing if tACS has any potential to change the abnormalities in connections of medial prefrontal cortex through this study. The study would potentially help us in understanding better about the role of medial prefrontal cortex in schizophrenia and potential of tACS stimulation at this site in improving schizophrenia symptoms.

PhD Scholar: Dr.Vanteemar S Sreeraj
Supervisor: Prof. Venkatasubramanian G.​
Funding: Candidate is supported by DBT-Wellcome Trust India Alliance funded Clinical Research Centre for Neuromodulation in Psychiatry