Event-related potential measures of gap detection threshold during natural sleep

• Published in: Clinical neurophysiology Vol. 125; no. 8; pp. 1647 - 1652
• Main Authors: Muller-Gass, Alexandra, Campbell, Kenneth
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ireland Ltd 01.08.2014
• Subjects: Acoustic Stimulation; Adult; Differential Threshold; Electroencephalography; ERPs; Evoked Potentials; Evoked Potentials, Auditory - physiology; Female; Gap detection; Humans; Male; Neurology; Objective threshold detection; Reaction Time - physiology; Reference Values; Sleep; Sleep - physiology; Sleep Stages - physiology; Sleep, REM - physiology; Speech Perception - physiology; Wakefulness - physiology; Young Adult; ERPs; Gap detection; P2; Sleep; N1; Objective threshold detection
• ISSN: 1388-2457; 1872-8952; 1872-8952
• DOI: 10.1016/j.clinph.2013.11.043

•Event-related potentials were used to provide an estimate of the gap detection threshold during sleep.•Gap detection thresholds could be accurately estimated while the subject was awake using the amplitude of N1, peaking at about 100ms and also during stage N2 of sleep using the amplitude of P2, peaking at about 200ms.•Only larger suprathreshold gaps were able to elicit N1 and P2 during REM sleep. The minimum time interval between two stimuli that can be reliably detected is called the gap detection threshold. The present study examines whether an unconscious state, natural sleep affects the gap detection threshold. Event-related potentials were recorded in 10 young adults while awake and during all-night sleep to provide an objective estimate of this threshold. These subjects were presented with 2, 4, 8 or 16ms gaps occurring in 1.5 duration white noise. During wakefulness, a significant N1 was elicited for the 8 and 16ms gaps. N1 was difficult to observe during stage N2 sleep, even for the longest gap. A large P2 was however elicited and was significant for the 8 and 16ms gaps. Also, a later, very large N350 was elicited by the 16ms gap. An N1 and P2 was significant only for the 16ms gap during REM sleep. ERPs to gaps occurring in noise segments can therefore be successfully elicited during natural sleep. The gap detection threshold is similar in the waking and sleeping states.