Special Seminar by Dr Anthony Harris

Title:
Influences of Neural Oscillation Phase on Perception: Controversies and Potential Resolutions

Abstract:

Rhythmic influences on neural processing have been shown numerous times at every level from synapse to behaviour and have inspired many theories of the role oscillations may play in neural computation. For example, neural firing probability has been shown to fluctuate across the oscillatory cycle in a number of cortical areas, with spikes being more likely to occur at some phases (e.g., troughs) and less likely at others (e.g., peaks). Despite this weight of evidence, however, the results of studies testing an association between oscillation phase and human perception and cognition are inconsistent. Recently, several null results have emerged in studies of phasic influences on perception, prompting questions about the replicability of prior work. More importantly, these results raise questions about whether oscillation phase has any impact on cognition, providing a challenge for oscillatory theories of the neural basis of cognition. In this talk I will describe my recent theoretical and empirical work exploring the boundary conditions of phase-dependence effects on perception. I will show how stimulus-induced phase resets can mask phase-dependence of behaviour, and how low oscillatory amplitude can corrupt phase estimates to a larger extent than has been previously appreciated. I will present recent evidence for robust effects of phase on perception and discuss challenges for the field going forward.