fMRI lag structure during waking up from early sleep stages.
Santiago Alcaide, Jacobo Sitt, Tomoyasu Horikawa, Alvaro Romano, Ana Carolina Maldonado, Agustin Ibanez, Mariano Sigman, Yukiyasu Kamitani, Pablo Barttfeld
Cortex; a journal devoted to the study of the nervous system and behavior September 1, 2021 DOI: 10.1016/j.cortex.2021.06.005 via PubMed
Summary
AI-generated from the abstractWaking up from early sleep involves a two-stage brain process. First, subcortical and sensorimotor structures activate before most cortical regions, followed by rapid whole-brain activation, with frontal regions engaging slightly later. A second, slower stage may then occur, where cortical regions activate before subcortical structures and the cerebellum. This pattern suggests subcortical structures play a key role in initiating and maintaining conscious states.
Study at a glance
| Characteristics | Analysis of pre-existing dataset Peer reviewed |
|---|---|
| Keywords | Consciousness Waking up FMRI |
| Citations | 13 |
| Key finding | Suddenly awakening from early sleep stages involves a two-stage process: first subcortical and sensorimotor structures activate before most cortical regions, followed by fast whole-brain activation, with frontal regions engaging later. |
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.