Selective Targeting of Cognitive Control Subnetworks with Spatiotemporally Optimized Transcranial Electrical Stimulation - 7 Project Summary/Abstract Cognitive control is a critical brain function essential for successful daily living that is affected in aging and disease. Cognitive control can be functionally and anatomically subdivided across two brain networks: a fronto-parietal net- work implicated in flexible behaviors (“task-switching”), and a cingulo-opercular network implicated in response conflict management. Activity in the theta-band among these areas has been associated with cognitive control, but the computational correlates and causal role of those oscillations remain unknown. Previous research has shown that cognitive control is susceptible to modulation by transcranial electrical stimulation (tES), but those ef- fects have been inconsistent to date, and their specificity and selectivity remain unknown. Refined spatiotemporal patterning of tES could permit selective targeting of cognitive control subnetworks (and thus selective interven- tion in cognitive control subfunctions), but lack of theory linking tES to neural activity at the population/network level has been a barrier to progress. This work will measure the effect of tES on neural population activity across large-scale brain networks in monkeys performing cognitive control tasks. Specifically, it will test spatially optimized stimuli predicted to focally target nodes of large-scale brain networks implicated in two, disso- ciable forms of cognitive control. It will furthermore systematically test temporal patterns of stimulation, with the aim of testing the hypothesis that long-range coordination of neural activity in the ⇠5-7 Hz theta band is a key mechanism for cognitive control. The conceptual innovation of this proposal is to tackle the question of how to selectively and specifically target cognitive control sub-functions through tES, while the technical innovation is to use spatiotemporally patterned tES, combined with neural population recordings in multiple brain areas. The successful completion of this proposed project will result in (1) an explanatory model linking tES protocols to resultant population patterns of neural activity within and between nodes of cognitive control sub-networks, and (2) specific stimulation protocols to selectively intervene in cognitive control sub-functions critical for successful daily living. The long-term goal of this work is to develop a comprehensive neurophysiological theory link- ing tES protocols to behavioral outcomes so that personalized, targeted interventions to affect cognition (including cognitive control, but also other cognitive functions of interest) can be developed on demand for basic research and clinical practice.