Research reportLack of sleep affects the evaluation of emotional stimuli
Introduction
The effects of sleep deprivation on neurocognitive processes are well documented [2]. Several studies have shown that the prefrontal cortex (PFC) is particularly sensitive to sleep loss [10], [25], [4] and that only one night of acute total sleep deprivation reduces performance on neuropsychological tasks such as those investigating working memory, decision making, task switching and attention [26], [19], [9], [7]. All these skills are subserved by the PFC. Moreover, neuroimaging studies have found that 24 h of continuous wakefulness are associated with significant reductions in metabolic activity within the prefrontal cortex, and, as a consequence, the PFC tasks performance is impaired (e.g., [25]).
The frontal lobes subserve not only the higher order cognitive abilities, but also emotion reactivity and behavioral inhibition (e.g., [18]). Amplified irritability and affective volatility are common complaints following sleepless nights [29], [24]. During prolonged sleep deprivation there is an increase in self-reported feelings of depressed mood, anger, frustration, tension and anxiety [6], [17]. In fact, a meta-analysis of consequences of sleep deprivation [23] showed that mood is more affected than performance measures following sleep deprivation.
While the effects of sleep loss on mood are well documented, on the other hand its specific impact on subjective reactivity to emotional stimuli has been surprisingly little studied. Without adequate sleep, negative reactions to adverse experiences appear to be significantly magnified, while positive reactions to pleasant events are often subdued. These effects on emotional reactivity can lead to negative consequences in real-word settings. As an example, it has been reported that sleep loss amplifies the negative emotive effects of disruptive daytime work events in medical residents [29].
Nevertheless, little is known about the specific effects of sleep loss on the subjective evaluation of emotional stimuli. It has been recently shown that sleep deprivation leads to a dysfunctionality of the MPFC–amygdala circuitry, accompanied by an increased negative evaluation of the emotional stimuli selected from the International Affective Picture System [28]. However, those pictures ranged from emotionally neutral to increasingly aversive (i.e., the pleasant pictures were discarded). Moreover, a dichotomic (unpleasant/neutral) emotionality rating was requested, instead of the typical valence rating on a continuous 1–9 scale [5].
In the present study we assessed the impact of one night of sleep deprivation on the emotional rating of a battery of affective visual stimuli selected from the International Affective Picture System (IAPS) [20], a set of static images based on a dimensional model of emotion. We hypothesized that, whether sleep deprivation causes an imbalance of the prefrontal–limbic circuitry, sleep-deprived and well-rested subjects should diverge in their evaluations of the affective stimuli. Given that judgments of emotional stimuli are not carried out in a dichotomous way, but continuously along the two dimensions of valence and arousal [5], we asked subjects to rate the pictures in terms of their ability to induce valence (unpleasant/pleasant) and arousal (calm/excited) changes.
Section snippets
Participants
Forty university students participated in this study (all females; mean age ± S.D.: 24.2 ± 4.2 years; range: 20–36 years).
None of the subjects had a history of medical, neurological or psychiatric disorders, neither of medication or drug intake. Moreover, each participant filled out the Toronto Alexithymia Scale (TAS-20) [1], to exclude alexithymic subjects (TAS-20 scores ≥61) and the Center for Epidemiological Studies Depression rating Scale (CES-D) [12] to exclude subjects with depression (CES-D
Subjective mood and alertness measures
ANOVA on Negative Mood Index (NMI) scores showed a significant main effect for Session (F1,38 = 5.73; p < 0.05), while the effect of Group only approached to significance (F1,38 = 3.41; p = 0.07). However, the Group × Session interaction was significant (F1,38 = 7.75; p < 0.01). Post hoc comparisons indicated that after one night of sleep deprivation subjects report a more negative mood than the non-deprived subjects (p < 0.01), while mood remains unchanged after a sleep night (see Fig. 1 panel A).
ANOVA on
Discussion
The purpose of this study was to investigate the effects of one night of sleep deprivation on the emotional valence and arousal subjective ratings of pleasant, neutral and unpleasant pictures in healthy humans. Different patterns of changes were observed for ratings of valence and arousal, in keeping with the view that these two dimensions reflect different aspects of emotional appraisal. Moreover, the analyses showed that valence rating was highest for unpleasant, intermediate for neutral and
Conflict of interest
The authors declare that they have no competing financial interests.
Acknowledgments
This study was supported in part by a MiUR grant to M. Ferrara (PRIN: n. 2007BNRWLP-003), and by a grant from the University of L’Aquila (Ricerche di Ateneo ex 60%).
References (29)
- et al.
The Twenty-Item Toronto Alexithymia Scale: I. Item selection and cross-validation of the factor structure
J. Psychosom. Res.
(1994) - et al.
Measuring emotion: the Self-Assessment Manikin and the Semantic Differential
J. Behav. Ther. Exp. Psychiatry
(1994) - et al.
How emotions inform judgment and regulate thought
Trends Cogn. Sci.
(2007) - et al.
Sleep deprivation alters pupillary reactivity to emotional stimuli in healthy young adults
Biol. Psychol.
(2009) - et al.
The effects of sleep deprivation on symptoms of psychopathology in healthy adults
Sleep Med.
(2007) - et al.
Effects of sleep deprivation and exercise on cognitive, motor performance and mood
Physiol. Behav.
(2006) - et al.
Behavioral and physiological consequences of sleep restriction
J. Clin. Sleep Med.
(2007) - et al.
Bad is stronger than good
Rev. Gen. Psychol.
(2001) - et al.
Patterns of performance degradation and restoration during sleep restriction and subsequent recovery: a sleep dose–response study
J. Sleep Res.
(2003) - et al.
The effects of 37 h of continuous wakefulness on the physiological arousal, cognitive performance, self-reported mood, and simulator flight performance of F-117A pilots
Mil. Psychol.
(2004)
Functional neuroimaging and behavioral correlates of capacity decline in visual short-term memory following sleep deprivation
Proc. Natl. Acad. Sci. U.S.A.
The effects of sleep and sleep deprivation on task switching performance
J. Sleep Res.
Sleep deprivation-induced reduction in cortical functional response to serial subtraction
Neuroreport
Neurocognitive consequences of sleep deprivation
Semin. Neurol.
Cited by (160)
Measurement type moderates the relationship between sleep and aggression: A meta-analytic investigation
2023, Aggression and Violent BehaviorAn experimental test of the effects of acute sleep deprivation on affect and avoidance
2022, Journal of Behavior Therapy and Experimental PsychiatrySleep and affect: A conceptual review
2022, Sleep Medicine ReviewsCitation Excerpt :For short-term self-reported duration, we found no evidence for an association with negative valence [54,65,66,68,69,87,88] and a possible null association with positive valence [54,65–67,88]. For short-term behavioral/physiological measures of duration, we found a possible null association with self-reported negative valence [49,70,76†,77†,79–82†,86†,89–92] (46% of studies involved sleep deprivation) but a negative association with behavioral/physiological measures of negative valence [49,76†,77†,90] (50% of studies involved sleep deprivation). Likewise, different findings depending on methods also emerged for arousal, where we found a possible null association with self-reported arousal [49,76†,80†,83,90,93] (33% of studies involved sleep deprivation) but a negative association with behavioral/physiological measures of arousal [76†,90,92,93] (25% of studies involved sleep deprivation).