Ultradian rhythms in the perception of two apparent motions.
Fourteen young adults were tested  on the spiral after-effect every 5 min and on the beta movement every 20 min for 8 continuous hrs. Time series analysis revealed significant 100-min rhythms in the perception of the two illusions, which also appeared to be sychronized across the experimental periods.
D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D009039:Motion Perception / Q000502:physiology*; D010507:Periodicity; D012890:Sleep / Q000502:physiology; D012895:Sleep, REM / Q000502:physiology