Abstract
Learning to interact with challenging sensory environments is a key visual function. One form of challenge comes when observers are asked to identify a target object that is obscured by irrelevant, distracting information. Brain oscillations (i.e. periodic modulation of neural excitability) are known to contribute to the minimisation of distractor impact. Entrainment of such oscillations has been shown to modulate perceptual and attentional processes in the visual system. Here, we tested whether a flicker entrainment intervention targeting an individual’s specific alpha frequency (8-12Hz) facilitates learning to detect a target in noise. Participants (n=80) were assigned to one of four groups. For the first 2 groups, entrainment pulses were presented at the individual alpha frequency for each participant and target stimuli were then aligned either to the peak (group 1) or the trough (group 2) of the induced oscillation. Group 3 was tested with the entrainment frequency mismatched (i.e. +/- 1 Hz) with the individual participant’s alpha frequency, while Group 4 was tested with non-periodic pulses (no entrainment control group). We found significantly higher learning rates for group 2 compared to all other groups; that is, when entrainment pulses matched the participant’s individual alpha and the stimuli were aligned with the trough of the oscillation. Further, we tested the effect of individualised entrainment on brain oscillations as measured by electroencephalography (EEG) data during training. Phase of stimulus presentation (group 1 vs. group 2) elicited differences in the early stimulus-locked response, related to stimulus processing, while individualized rate of entrainment (group 2 vs. group 3; matched vs mismatched) produced differences in cross-frequency band synchronisation. These results suggest a cascade of neural interactions related to learning and propose an important role for individualized entrainment in learning interventions.