NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Time-on-task decrements in "steer clear" performance of patients with sleep apnea and narcolepsyLoss of attention with time-on-task reflects the increasing instability of the waking state during performance in experimentally induced sleepiness. To determine whether patients with disorders of excessive sleepiness also displayed time-on-task decrements indicative of wake state instability, visual sustained attention performance on "Steer Clear," a computerized simple RT driving simulation task, was compared among 31 patients with untreated sleep apnea, 16 patients with narcolepsy, and 14 healthy control subjects. Vigilance decrement functions were generated by analyzing the number of collisions in each of six four-minute periods of Steer Clear task performance in a mixed-model analysis of variance and linear regression equations. As expected, patients had more Steer Clear collisions than control subjects (p=0.006). However, the inter-subject variability in errors among the narcoleptic patients was four-fold that of the apnea patients, and 100-fold that of the controls volunteers; the variance in errors among untreated apnea patients was 27-times that of controls. The results of transformed collision data revealed main effects for group (p=0.006), time-on-task (p=0.001), and a significant interaction (p=0.022). Control subjects showed no clear evidence of increasing collision errors with time-on-task (adjusted R2=0.22), while apnea patients showed a trend toward vigilance decrement (adjusted R2=0.42, p=0.097), and narcolepsy patients evidenced a robust linear vigilance decrement (adjusted R2=0.87, p=0.004). The association of disorders of excessive somnolence with escalating time-on-task decrements makes it imperative that when assessment of neurobehavioral performance is conducted in patients, it involves task durations and analyses that will evaluate the underlying vulnerability of potentially sleepy patients to decrements over time in tasks that require sustained attention and timely responses, both of which are key components in safe driving performance.
Document ID
20040141812
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Findley, L. J.
(Sleep Disorders Center of Northern Colorado Loveland, United States)
Suratt, P. M.
Dinges, D. F.
Date Acquired
August 22, 2013
Publication Date
September 15, 1999
Publication Information
Publication: Sleep
Volume: 22
Issue: 6
ISSN: 0161-8105
Subject Category
Life Sciences (General)
Funding Number(s)
CONTRACT_GRANT: HL42236
CONTRACT_GRANT: NR04281
Distribution Limits
Public
Copyright
Other
Keywords
NASA Discipline Space Human Factors
Non-NASA Center

Available Downloads

There are no available downloads for this record.
No Preview Available