Brain Stimulation Effects on Cognitive Task Performance

Transcranial magnetic stimulation (TMS) is a non-invasive form of brain stimulation that relies on rapidly changing magnetic fields to influence neuronal firing rates. TMS can be used to temporarily inhibit or enhance the firing of populations of neurons located in the cerebral cortex. TMS-induced cortical inhibition versus enhancement is increasingly being used as a tool for exploring brain-behavior relationships and for improving cognitive functioning in people experiencing cognitive deficits due to neuropsychiatric illness (e.g., dementia and schizophrenia). However, important and unresolved methodological issues in this field concern the optimal design of cognitive tasks for TMS stimulation protocols. The purpose of this study is to determine optimal design protocols for online TMS studies of cognitive processes involved in attention, learning, and memory. Research participants will complete cognitive tasks while active versus sham (i.e., non-stimulating) TMS is applied to the brain. A factorial design will be used to determine the combination of task and TMS parameters (i.e., device settings) that produce the most robust and reliable behavioral effects.