Cognitive Neuroscience


Cortex; a journal devoted to the study of the nervous system and behavior




Formal publication: July 2021

Authors: Alcaide, S., Sitt, J., Horikawa, T., Romano, A., Maldonado, A. C., Ibanez, A., Sigman, M., Kamitani, Y., & Barttfeld, P.

Abstract: The brain mechanisms by which we transition from sleep to a conscious state remain largely unknown in humans, partly because of methodological challenges. Here we study a pre-existing dataset of waking up participants originally designed for a study of dreaming (Horikawa, Tamaki, Miyawaki, & Kamitani, 2013) and suggest that suddenly awakening from early sleep stages results from a two-stage process that involves a sequence of cortical and subcortical brain activity. First, subcortical and sensorimotor structures seem to be recruited before most cortical regions, followed by fast, ignition-like whole-brain activation-with frontal regions engaging a little after the rest of the brain. Second, a comparably slower and possibly mirror-reversed stage might take place, with cortical regions activating before subcortical structures and the cerebellum. This pattern of activation points to a key role of subcortical structures for the initiation and maintenance of conscious states.