tACS- What goes on inside? The neural consequences of transcranial alternating current stimulation

There is considerable evidence for clinical and behavioral efficacy of transcranial alternating current stimulation (tACS). The effects range from suppressing Parkinsonian tremors to augmenting human learning and memory. Despite widespread use, the neurobiological mechanism of actions of tACS on the brain is unclear. We have taken a threefold approach to probe tACS mechanisms. First, we examined the behavioral effects of tACS on human motion perception. Second, we used known motion models to generate predictions about neural mechanisms that could produce the effects. Third, we tested these predictions by directly measuring tACS-induced neural activity changes in the macaque brain.