Related Experiment Video
Updated: Aug 6, 2026

Investigating the Effects of Antipsychotics and Schizotypy on the N400 Using Event-Related Potentials and Semantic Categorization
Published on: November 19, 2014
EEG spectral activity during paradoxical sleep: further evidence for cognitive processing
C Jouny1, F Chapotot, H Merica
1Division de Neuropsychiatrie, H pitaux Universitaires de Genève, Switzerland.
Abstract:
Paradoxical sleep (PS), in which periods with (phasic) and without (tonic) rapid eye movements are intermingled, is hypothesized to be related to cognitive processing and dreaming. Based on polysomnographic data from 12 healthy subjects, this study focuses on the spectral differentiation between phasic and tonic periods. Phasic PS periods exhibited decreased theta and alpha power in the posterior brain areas suggesting the interference of visual processing related to dream imagery. Phasic PS periods were also characterized by a shift from beta to gamma activity in frontal, central and occipital areas reflecting specific phasic related activation. Together, these findings bring new evidence for the existence of visual imagery and cognitive processing during phasic PS.
Related Concept Videos
Brain Waves
Sleep-Wake Cycles
NREM Sleep
NREM sleep comprises four progressive stages that seamlessly merge:
Stages of Sleep
Before sleep begins, in wakefulness, the brain exhibits primarily beta waves, which are high in frequency and low in amplitude, indicating alertness...
REM Sleep Behavior Disorder
RBD is significantly associated with...

