Abstract
Reduced cortical inhibition by somatostatin-expressing (SST) interneurons has been strongly associated with treatment-resistant depression. However, whether the effects of reduced SST inhibition on microcircuit activity have signatures detectible in electroencephalography (EEG) signals remains unknown. We simulated resting-state activity and EEG using detailed models of human cortical layer 2/3 microcircuits with normal (healthy) or reduced SST inhibition (depression). Healthy microcircuit models showed emergent key features of resting-state EEG, and depression microcircuits exhibited increased theta, alpha and low beta power (4 - 15 Hz). The changes in depression involved a combination of an aperiodic broadband, and periodic theta and low beta components. In both conditions, neuronal spiking showed a spike preference for the phase preceding the EEG trough. Our study thus links SST inhibition level to features in EEG simulated from detailed human microcircuits, which can serve to better identify mechanistic subtypes of depression using EEG, and non-invasively monitor modulation of cortical inhibition.
Competing Interest Statement
The authors have declared no competing interest.
Footnotes
revised abstract