Neuromodulation of temporal prediction using tACS

Abstract

Abstract Predicting the onset of upcoming events and objects in the environment enables the optimisation of action and perception. Studies on temporal prediction in non-rhythmic stimulation provide evidence that low-frequency neural oscillations underlie temporal prediction processes.1 By adjusting their phase to the temporal structure of predictable environmental stimuli, the time point of the onset of relevant information might be predicted, which would facilitate sensory processing. This study aims to address the relation between oscillatory activity and temporal predictions. Based on simulations of electrical currents using a realistic three-shell head model2, we applied delta transcranial alternating current stimulation (tACS) over the left and right parietal cortex in 27 young, healthy adults. The participants had to solve a temporal prediction task while tACS was applied at six different phase lags in an intermittent experimental design. With this study, we explored the impact of the modulation of parietal regions with delta tACS on temporal prediction. Specifically, we investigated whether entrainment of neural activity by tACS leads to more consistent temporal judgements, compared to an active control condition, as reflected in an increased slope of the psychometric functions. Moreover, inter-individual phase-specific aftereffects and, thus, differences in behavioural performance for different tACS phase lags were examined. Research Category and Technology and Methods Basic Research: 8. Transcranial Alternating Current Stimulation (tACS) Keywords: tACS, phase-specificity, low-frequency oscillations, temporal prediction