Predicting the stream of consciousness from activity in human visual cortex.
Current biology : CB July 26, 2005 John-Dylan Haynes, Geraint Rees
The stream of conscious experience, even when it changes rapidly and spontaneously, can be predicted from brain activity alone. Using binocular rivalry to induce frequent, involuntary shifts in perception without altering what the eyes see, researchers measured brain activity with fMRI. Multivariate pattern analysis of signals from visual cortex accurately tracked participants' reported conscious experience as it fluctuated. Prediction in primary visual cortex relied on eye-based signals, while higher visual areas reflected the color of the percept. Accurate prediction was also possible using signals recorded during stable viewing, showing the method generalizes across conditions and does not depend on motor responses.