Decoding the dynamics of conscious perception: The temporal generalization method

Abstract

Parsing a cognitive task into a sequence of successive operations is a central problem in cognitive neuroscience. A major advance is now possible thanks to the application of pattern classifiers to time-resolved recordings of brain activity [electro-encephalography (EEG), magneto-encephalography (MEG), or intracranial recordings]. The method determines precisely when a specific mental content becomes explicitly represented in brain activity. Most importantly, the ability of these pattern classifiers to generalize across time and experimental conditions sheds light on the temporal organization of information-processing stages. To illustrate these ideas, we show how the decoding of MEG and EEG recordings can be used to track the fate of conscious and unconscious brain processes during simple masking and auditory novelty tasks. The experimental results yield converging results, suggesting that conscious perception is associated with the late formation of a distributed and stable neural assembly that encodes the content of subjective perception.