Patterns of performance degradation and restoration during sleep restriction and subsequent recovery: a sleep dose‐response study

Abstract

SUMMAR Y Daytime performance changes were examined during chronic sleep restriction or augmentation and following subsequent recovery sleep. Sixty-six normal volunteers spent either 3 (n ¼ 18), 5 (n¼ 16), 7 (n ¼ 16), or 9 h (n ¼ 16) daily time in bed (TIB) for 7 days (restriction ⁄ augmentation) followed by 3 days with 8 h daily TIB (recovery). In the 3-h group, speed (mean and fastest 10% of responses) on the psychomotor vigilance task (PVT) declined, and PVT lapses (reaction times greater than 500 ms) increased steadily across the 7 days of sleep restriction. In the 7-and 5-h groups speed initially declined, then appeared to stabilize at a reduced level; lapses were increased only in the 5-h group. In the 9-h group, speed and lapses remained at baseline levels. During recovery, PVT speed in the 7-and 5-h groups (and lapses in the 5-h group) remained at the stable, but reduced levels seen during the last days of the experimental phase, with no evidence of recovery. Speed and lapses in the 3-h group recovered rapidly following the first night of recovery sleep; however, recovery was incomplete with speed and lapses stabilizing at a level comparable with the 7-and 5-h groups. Performance in the 9-h group remained at baseline levels during the recovery phase. These results suggest that the brain adapts to chronic sleep restriction. In mild to moderate sleep restriction this adaptation is sufficient to stabilize performance, although at a reduced level. These adaptive changes are hypothesized to restrict brain operational capacity and to persist for several days after normal sleep duration is restored, delaying recovery.k e y w o r d s chronic sleep

Response surface mapping of neurobehavioral performance: Testing the feasibility of split sleep schedules for space operations

“…In agreement with the results of earlier dose-response studies of chronic sleep restriction [2,3], psychomotor vigilance task performance, digit symbol substitution task performance, and subjective assessments of sleepiness were observed to be primarily a function of total time in bed per 24 h, with less total time in bed consistently resulting in greater accumulation of performance impairment and subjective sleepiness across days. For psychomotor vigilance performance and subjective sleepiness, the rate of impairment across days was found to be approximately linearly related to total time in bed per 24 h. For psychomotor vigilance, the current findings are in agreement with the results of an earlier dose-response study [2]; however the previous study did not explicitly model the relationship of rate of change to daily time in bed for subjective sleepiness.…”

“…One such reduced model assumed that there was no interaction between anchor and nap sleep: (2) Here, the rate of change of neurobehavioral performance across sleep restriction days is no longer idiosyncratic for each condition, but depends on the TIB for anchor sleep (through β) independent of nap sleep duration and vice versa on the TIB for nap sleep (through γ) independent of anchor sleep duration. A further reduced model assumed linearity over conditions: (3) where β and γ are now rate constants (e.g., for every hour of additional anchor sleep, the rate of change of neurobehavioral performance across sleep restriction days is altered by β); and α is an overall intercept.…”

“…Objective evidence from virtually all NASA space missions indicates that astronaut sleep is restricted in space flight, averaging between 4h and 6.5h per day, as a result of endogenous disturbances of sleep (e.g., motion sickness, circadian desynchrony), environmental disruptions, and frequently, curtailment of sleep due to the work demands [1]. Ground based experiments indicate that cognitive performance deficits progressively worsen (i.e., accumulate) over consecutive days when sleep is restricted to levels experienced by astronauts [2,3]. The detrimental consequences of sleep restriction manifest in a range of critical functions including increased lapses of attention, degradation of response times, deficits in complex problem solving, reduced learning, increased negative mood, and disruption of essential endocrine, metabolic, and immune responses [4,5].…”

Sleep and performance in simulated Navy watch schedules

“…3, left panel). This is in agreement with earlier laboratory studies demonstrating cumulative performance impairment due to sustained sleep restriction (Belenky et al, 2003;Van Dongen et al, 2003Mollicone et al, 2008). Furthermore, there was more variability in psychomotor impairment across the 24 h of the day in the 5/15 watch schedule than in the 3/9 watch schedule (see Fig.…”

Dawn simulation light impacts on different cognitive domains under sleep restriction

“…Chronic sleep restriction (SR) has deleterious effects not only on daytime alertness but also on cognitive performance [4,5].…”