Plain Language Summary
Previous research suggests that vigilant attention deficits may be the general factor underlying cognitive impairments following sleep deprivation. However, the detrimental effect of sleep loss on inhibition control and its relationship to vigilant attention impairment after sleep deprivation remains unclear. Here we examined the extent to which performance deficits in the Go/No-Go task are explained by vigilant attention impairments after TSD and PSR. The results demonstrate that both TSD and PSR significantly impair inhibition control, which can be partly explained by vigilant attention deficits. These findings support the fundamental role of vigilant attention in maintaining neurobehavioral function during insufficient sleep.
Sleep accounts for about a third of our time and is an indispensable part of human life. However, with the development of science and technology, and the acceleration of the pace of life, the phenomenon of sleep loss has become a significant public health concern. Partial sleep restriction (PSR) and total sleep deprivation (TSD) are two common forms of sleep deprivation. Many previous studies demonstrate that both forms of sleep loss can negatively affect an individual’s cognition, mood, and physical health.1–8
Inhibition control refers to the ability to choose appropriate responses while suppressing inappropriate and unwanted behavior. It is a core component of executive function and is essential for controlling human behavior.9,10 Deficient inhibition control may negatively affect individuals’ career goals and social relationships.11 Poor inhibition control is generally associated with the attentional deficits shown by attention deficit hyperactivity disorder patients, violence, drug addiction, and suicidal behavior.12 One of the most commonly used paradigm for measuring inhibition control is the Go/No-Go task, which requires individuals to respond as quickly as possible to select stimuli while withholding a response to all other stimuli.13
Due to the prevalence of sleep loss and the importance of inhibition control, many researchers have explored the effects of sleep disturbance or sleep deprivation on inhibition control.14 For example, one previous event-related potentials (ERP) study found that poor sleep affects the speed to inhibit a motor response as well as the intensity of pre-motor inhibitory processes and task-relevant information processing,15 while a more recent study found that sleep deprivation impairs memory control with sleep-deprived participants showing more unsuccessful suppression of intrusions of emotionally negative and neutral scenes than rested participants.16 However, the effects of both total and partial sleep deprivation on inhibition control are not consistent. In TSD experiments, some studies have found that inhibition control is significantly diminished from baseline after TSD,17–22 while others found no significant changes.23 Similarly, some studies using PSR have found that inhibition control is decreased significantly after sleep loss.24–28 However, some other studies found no significant changes in inhibition control after PSR.29,30
Several factors may contribute to the inconsistencies in the literature. For example, some sleep deprivation studies were conducted outside of the laboratory,24,27,28 and many confounding variables (eg, room temperature, noise, interactions with family members) may not have been well controlled. Moreover, different task paradigms and lengths of sleep deprivation or sleep restriction protocols have been used in previous studies.25–31 For example, one ERP study used the Go/No-Go ERP paradigm and found that accuracy of detection of the rarely occurring Go and No-Go stimuli significantly declined after 24 h and 36 h of continued wakefulness. Moreover, the amplitudes of both the Go and No-Go P300 components were also significantly reduced after 24 h and 36 h of continuous wakefulness, suggesting that sleep deprivation may not have a specific effect on inhibition.32 In contrast, another study explored the effect of noise-induced sleep disturbances on inhibition functions in a visual Go/No-Go task and found that decision processes underlying overt responses were less vulnerable to disturbed sleep than inhibition processes.33 Since the underlying mechanisms that drive the adverse effects of TSD and PSR may not be the same,34 more rigorous laboratory studies are needed to investigate the effects of both TSD and PSR on inhibition control.
In addition to inhibition control, many studies have consistently demonstrated the detrimental effects of sleep loss on a range of other cognitive domains, such as attention and working memory. Although the sensitivity of cognitive tasks to sleep deprivation varies widely,35 previous studies have shown that both TSD and PSR yield significant impairments in vigilant attention.2,7,8,36–39 Because vigilant attention is essential for high-level cognition functions and is most susceptible to sleep deprivation, it has been proposed that vigilant attention may be the fundamental factor that explains much of the variance in other cognitive deficits following sleep deprivation.40 This hypothesis highlights the importance of vigilant attention and suggests that high-level cognitive functions will be impaired if an individual is not sufficiently vigilant to perform a task.40–42 Although this hypothesis has existed for years, few studies have explicitly examined the relationships between vigilant attention and performance on the inhibition control tasks under conditions of sleep loss.
The aims of the present study were to examine the effects of both TSD and PSR on inhibition control and determine whether impairments in inhibition control induced by TSD and PSR can be explained by deficits in vigilant attention, testing the Vigilance Hypothesis.33 The data for the current analyses were derived from two separate sleep deprivation experiments. Experiment 1 examined the effects of one night of TSD on inhibition control and the relationship between inhibition control and vigilant attention following TSD. We hypothesized that (1) after a night of TSD, inhibition control and vigilant attention would be significantly impaired when compared to baseline sleep; and that (2) changes in inhibition control would be correlated with changes in vigilant attention after TSD. Experiment 2 investigated the effects of two nights of PSR on inhibition control and the relationship between inhibition control and vigilant attention. Similarly, we hypothesized that (1) compared with baseline, the level of individual inhibition control and vigilant attention would decrease under PSR, with greater deficits observed after two nights of PSR; and that (2) deficits in individual inhibition control would also be correlated with deficits in vigilant attention after PSR.
Materials and Methods
Experiment 1: Effects of TSD on Inhibition Control
A total of 65 healthy adults participated in the experiment. Forty-nine of these adults (mean age 34.1 ± 8.7 years, 18 females, all right-handed) participated in the TSD condition, and 16 (mean age 35.7 ± 8.6 years, seven females, all right-handed) participated in the control group study. All participants were nonsmokers and had no acute or chronic medical and psychological conditions. As assessed by circadian rhythm questionnaires43 and actigraphy, all participants had a regular bedtime (22:00–00:00) and wake time (06:00–09:00) with a total sleep time duration of 6.5 to 8 hours, and no habitual napping. Individuals were excluded if they participated in shift work, traveled across time zones, or had irregular sleep-wake routines in the 60 days before the study. Individuals with sleep disorders were excluded by a night of laboratory polysomnography and oximetry measurements. Bedtimes and wake times of enrolled participants were assessed by actigraphy, sleep logs, and…
Read More:Total sleep deprivation and partial sleep restriction | NSS