Discrepancy between subjective symptomatology and objective neuropsychological performance in insomnia.
OBJECTIVE
While daytime impairment is a defining feature of primary insomnia (PI), prior research using objective measures has not yielded clear and reliable evidence of global or specific deficits. In this investigation subjective and neuropsychological measures of daytime impairment were concurrently evaluated in subjects with primary insomnia (PIs) and in healthy good sleeper subjects (GSs). The goals for the study were to assess (1) whether PIs differ from GSs on subjective and/or objective measures and (2) the extent to which subjective and objective measures provide discordant information.


METHODS
Subjects were evaluated on multiple self-report measures of sleep and daytime performance and were administered a comprehensive set of neuropsychological tests.


METHODS
The University of Rochester Sleep and Neurophysiology Research Laboratory (Rochester, NY).


METHODS
Forty-nine subjects (32 PIs and 17 GSs). Seventy-one percent of the sample was female; average age 39 +/- 11 yrs.


RESULTS
Overall, PIs reported worse sleep, diminished activity levels, and a greater number and severity of daytime complaints. However, PIs did not show deficits on neuropsychological tests. Additionally, neuropsychological measures were not associated with severity of daytime complaints. Objectively measured sleep was found to be associated with performance (motor speed), while prospective and objective sleep measures were associated with level of daytime complaint.


CONCLUSIONS
The discrepancy between subjective daytime complaints and objective performance in individuals with insomnia is common, but poorly understood. This discordance may suggest that daytime impairment corresponds less to "output" and more to attentional bias or to the realistic appraisal that "effort" is required to maintain normal performance.
Orff
Henry J
HJ
Joint Doctoral Program in Clinical Psychology, San Diego State University and University of California, San Diego, CA, USA.
Drummond
Sean P A
SP
Nowakowski
Sara
S
Perils
Michael L
ML
D000328:Adult; D003071:Cognition; D003072:Cognition Disorders / Q000175:diagnosis / Q000209:etiology*; D005260:Female; D006801:Humans; D008297:Male; D008568:Memory; D008875:Middle Aged; D009483:Neuropsychological Tests; D010465:Perception; D017286:Polysomnography; D011597:Psychomotor Performance; D011930:Reaction Time; D007319:Sleep Initiation and Maintenance Disorders / Q000150:complications*; D013647:Task Performance and Analysis