Citation

Yong Z, Tan JH, Hsieh PJ. J. Neurophysiol. 2019; ePub(ePub): ePub.

Affiliation

National Taiwan University, Taiwan.

Copyright

(Copyright © 2019, American Physiological Society)

DOI

10.1152/jn.00825.2018

PMID

31553690

Abstract

Microsleeps are brief episodes of arousal level decrease manifested through behavioral signs. Brain activity during microsleep in the presence of external stimulus remain poorly understood. In this study, we sought to understand neural responses to auditory stimulation during microsleep. We gave participants the simple task of listening to audios of different pitches and amplitude modulation frequencies during early afternoon fMRI scans. We found that: 1. Microsleep was associated with cortical activations in broad motor and sensory regions and deactivations in thalamus, irrespective of auditory stimulation. 2. High and low pitch audios elicited different activity patterns in the auditory cortex during awake but not microsleep state. 3. During microsleep, spatial activity patterns in broad brain regions were similar regardless of the presence or types of auditory stimulus (i.e. stimulus-invariant). These findings show that the brain is highly active during microsleep, but the activity patterns across broad regions are unperturbed by auditory inputs.

Language: en

Keywords

Arousal fluctuation; MVPA; activity pattern; microsleep; stimulus invariant