Stanford Psychiatry’s Ethan Solomon receives grant to research theta burst modulation of hippocampal networks in schizophrenia

We are pleased to share that Stanford Psychiatry’s Ethan Solomon, Instructor of Psychiatry and Behavioral Sciences, has received a K99 grant from the National Institute of Mental Health titled “Theta burst modulation of hippocampal-cortical rhythms in schizophrenia.”

Schizophrenia affects nearly 1% of people worldwide and manifests with disorganized thoughts, delusions, hallucinations, and profound deficits in core cognitive functions. The hippocampus, the seat of memory and relational information processing in the brain, plays a key role in the development and progression of schizophrenia. The disorder might emerge, in part, from a breakdown in the rhythmic patterns of brain activity – sometimes called brainwaves – that coordinate activity between the hippocampus and the cortex. However, we do not know if these rhythms are responsive to neuromodulation, and whether affecting these rhythms can alleviate schizophrenia symptoms.

Theta burst-stimulation (TBS) mimics the natural hippocampal theta rhythm and has been used to alter hippocampal function in healthy humans by targeting the posterior parietal node of the hippocampal-cortical network – a spot on the back of the head. Dr. Solomon’s research will explore whether connectivity-guided TBS to this parietal node can affect hippocampal neural activity and cognitive function in schizophrenia patients. The research will advance our understanding of how the brain responds to theta burst stimulation (also used in conditions like major depression) and whether this form of stimulation can be used to alter hippocampal physiology and cognitive function in patients with schizophrenia.

“Schizophrenia — marked by delusions, hallucinations, and cognitive deficits — causes the most disability of any mental health condition, but existing treatments have significant side effect burden and are often ineffective,” says Dr. Solomon. “This project will address a major gap in our understanding of hippocampal physiology, schizophrenia pathophysiology, and potential avenues to use brain stimulation as a therapeutic tool in this devastating illness.”

Dr. Solomon is a member of the Stanford Precision Neurotherapeutics Lab. The Precision Neurotherapeutics Lab studies the fundamental principles of human brain plasticity and is building transdiagnostic real-time monitoring platforms for personalized neurotherapeutics. Dr. Solomon will work with a mentoring team of world-class experts in invasive and non-invasive brain stimulation and schizophrenia, including Drs. Corey Keller, Josef Parvizi, and Jacob Ballon, along with advisors Drs. Karl Deisseroth and Fabio Ferrarelli (University of Pittsburgh). Recent publications and presentations by Dr. Solomon and colleagues include “Ketamine Increases Theta Oscillations and Cortical Connectivity of the Human Hippocampus,” presented at the Society of Biological Psychiatry, and “TMS provokes target-dependent intracranial rhythms across human cortical and subcortical sites,” published in Brain Stimulation.

More Information

For more details about this project, visit NIH RePORTER.