A resting-state EEG dataset for sleep deprivation.

To investigate the impact of sleep deprivation (SD) on mood, alertness, and resting-state electroencephalogram (EEG), we present an eyes-open resting-state EEG dataset. The dataset comprises EEG recordings and cognitive data from 71 participants undergoing two testing sessions: one involving SD and the other normal sleep. In each session, participants engaged in eyes-open resting-state EEG. The Psychomotor Vigilance Task (PVT) was employed for alertness measurement. Emotional and sleepiness were measured using Positive and Negative Affect Scale (PANAS) and Stanford Sleepiness Scale (SSS). Additionally, to examine the influence of individual sleep quality and traits on SD, Pittsburgh Sleep Quality Index (PSQI) and Buss-Perry Aggression Questionnaire (BPAQ) were utilized. This dataset's sharing may contribute to open EEG measurements in the field of SD.

Sleep loss and emotion: A systematic review and meta-analysis of over 50 years of experimental research.

In a largely sleep-deprived society, quantifying the effects of sleep loss on emotion is critical for promoting psychological health. This preregistered systematic review and meta-analysis quantified the effects of various forms of sleep loss on multiple aspects of emotional experiences. Eligible studies used experimental reductions of sleep via total sleep deprivation, partial sleep restriction, or sleep fragmentation in healthy populations to examine effects on positive affect, negative affect, general mood disturbances, emotional reactivity, anxiety symptoms, and/or depressive symptoms. In total, 1,338 effect sizes across 154 studies were included (N = 5,717; participant age range = 7-79 years). Random effects models were conducted, and all forms of sleep loss resulted in reduced positive affect (standardized mean difference [SMD] = -0.27 to -1.14), increased anxiety symptoms (SMD = 0.57-0.63), and blunted arousal in response to emotional stimuli (SMD = -0.20 to -0.53). Findings for negative affect, reports of emotional valence in response to emotional stimuli, and depressive symptoms were mixed and depended on the type of sleep loss. Nonlinear effects for the amount of sleep loss as well as differences based on the stage of sleep restricted (i.e., rapid eye movement sleep or slow-wave sleep) were also detected. This study represents the most comprehensive quantitative synthesis of experimental sleep and emotion research to date and provides strong evidence that periods of extended wakefulness, shortened sleep duration, and/or nighttime awakenings adversely influence human emotional functioning. Findings provide an integrative foundation for future research on sleep and emotion and elucidate the precise ways that inadequate sleep may impact our daytime emotional lives. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Childhood adversity is associated with heightened inflammation after sleep loss.

OBJECTIVES: To investigate whether childhood adversity exacerbates the relationship between sleep restriction and inflammation. METHODS: Participants (N = 46) were randomly assigned to an experimental sleep restriction group (n = 25) or a night of typical sleep (n = 21). Participants provided a dried blood spot sample the morning before and after the experimental night. RESULTS: A significant interaction emerged between childhood adversity and group assignment on C-reactive protein (CRP) after the experimental night (Beta = -0.02, SE = 0.01, P = .03, 95% CI: -0.05, -0.002). Sleep restriction resulted in an increase in CRP at high levels of childhood adversity (+1 SD; Effect = -0.57, SE = 0.15, P< .001; 95% CI: -0.87, -0.26) but not low levels of childhood adversity (Effect = -0.08, SE = 0.10, P = .40; 95% CI: -0.29, 0.12). CONCLUSION: Childhood adversity may amplify the effect of sleep loss on markers of inflammation.

Sleep improvements on days with later school starts persist after 1 year in a flexible start system.

Early school times fundamentally clash with the late sleep of teenagers. This mismatch results in chronic sleep deprivation posing acute and long-term health risks and impairing students' learning. Despite immediate short-term benefits for sleep, the long-term effects of later starts remain unresolved. In a pre-post design over 1 year, we studied a unique flexible school start system, in which 10-12th grade students chose daily between an 8:00 or 8:50AM-start. Missed study time (8:00-8:50) was compensated for during gap periods or after classes. Based on 2 waves (6-9 weeks of sleep diary each), we found that students maintained their ~ 1-h-sleep gain on later days, longitudinally (n = 28) and cross-sectionally (n = 79). This gain was independent of chronotype and frequency of later starts but attenuated for boys after 1 year. Students showed persistently better sleep quality and reduced alarm-driven waking and reported psychological benefits (n = 93) like improved motivation, concentration, and study quality on later days. Nonetheless, students chose later starts only infrequently (median 2 days/week), precluding detectable sleep extensions in the flexible system overall. Reasons for not choosing late starts were the need to make up lost study time, preference for extra study time and transport issues. Whether flexible systems constitute an appealing alternative to fixed delays given possible circadian and psychological advantages warrants further investigation.

Hyperexcitable arousal circuits drive sleep instability during aging.

Sleep quality declines with age; however, the underlying mechanisms remain elusive. We found that hyperexcitable hypocretin/orexin (Hcrt/OX) neurons drive sleep fragmentation during aging. In aged mice, Hcrt neurons exhibited more frequent neuronal activity epochs driving wake bouts, and optogenetic activation of Hcrt neurons elicited more prolonged wakefulness. Aged Hcrt neurons showed hyperexcitability with lower KCNQ2 expression and impaired M-current, mediated by KCNQ2/3 channels. Single-nucleus RNA-sequencing revealed adaptive changes to Hcrt neuron loss in the aging brain. Disruption of Kcnq2/3 genes in Hcrt neurons of young mice destabilized sleep, mimicking aging-associated sleep fragmentation, whereas the KCNQ-selective activator flupirtine hyperpolarized Hcrt neurons and rejuvenated sleep architecture in aged mice. Our findings demonstrate a mechanism underlying sleep instability during aging and a strategy to improve sleep continuity.

A clinical trial to evaluate the dayzz smartphone app on employee sleep, health, and productivity at a large US employer.

Sleep deficiency is a hidden cost of our 24-7 society, with 70% of adults in the US admitting that they routinely obtain insufficient sleep. Further, it is estimated that 50-70 million adults in the US have a sleep disorder. Undiagnosed and untreated sleep disorders are associated with diminished health for the individual and increased costs for the employer. Research has shown that adverse impacts on employees and employers can be mitigated through sleep health education and sleep disorder screening and treatment programs. Smartphone applications (app) are increasingly commonplace and represent promising, scalable modalities for such programs. The dayzz app is a personalized sleep training program that incorporates assessment of sleep disorders and offers a personalized comprehensive sleep improvement solution. Using a sample of day workers affiliated with a large institution of higher education, we will conduct a single-site, parallel-group, randomized, waitlist control trial. Participants will be randomly assigned to either use the dayzz app throughout the study or receive the dayzz app at the end of the study. We will collect data on feasibility and acceptability of the dayzz app; employee sleep, including sleep behavioral changes, sleep duration, regularity, and quality; employee presenteeism, absenteeism, and performance; employee mood; adverse and safety outcomes; and healthcare utilization on a monthly basis throughout the study, as well as collect more granular daily data from the employee during pre-specified intervals. Our results will illuminate whether a personalized smartphone app is a viable approach for improving employee sleep, health, and productivity. Trial registration: ClinicalTrials.gov Identifier: NCT04224285.

The cyclic interaction between daytime behavior and the sleep behavior of laboratory dogs.

Sleep deprivation has been found to negatively affect an individual´s physical and psychological health. Sleep loss affects activity patterns, increases anxiety-like behaviors, decreases cognitive performance and is associated with depressive states. The activity/rest cycle of dogs has been investigated before, but little is known about the effects of sleep loss on the behavior of the species. Dogs are polyphasic sleepers, meaning the behavior is most observed at night, but bouts are also present during the day. However, sleep can vary with ecological and biological factors, such as age, sex, fitness, and even human presence. In this study, kennelled laboratory adult dogs' sleep and diurnal behavior were recorded during 24-h, five-day assessment periods to investigate sleep quality and its effect on daily behavior. In total, 1560 h of data were analyzed, and sleep metrics and diurnal behavior were quantified. The relationship between sleeping patterns and behavior and the effect of age and sex were evaluated using non-parametric statistical tests and GLMM modelling. Dogs in our study slept substantially less than previously reported and presented a modified sleep architecture with fewer awakenings during the night and almost no sleep during the day. Sleep loss increased inactivity, decreased play and alert behaviors, while increased time spent eating during the day. Males appeared to be more affected by sleep fragmentation than females. Different age groups also experienced different effects of sleep loss. Overall, dogs appear to compensate for the lack of sleep during the night by remaining inactive during the day. With further investigations, the relationship between sleep loss and behavior has the potential to be used as a measure of animal welfare.

Changes in ventromedial prefrontal cortex functional connectivity are correlated with increased risk-taking after total sleep deprivation.

There is evidence indicating that people are more likely to take risks when they are sleep-deprived than during resting wakefulness (RW). The ventromedial prefrontal cortex (vmPFC) could have a crucial psychophysiological role in this phenomenon. However, the intrinsic patterns of functional organization of the human vmPFC and their relationship with risk-taking during sleep deprivation (SD) are unclear. This study investigated the relationship between functional connectivity in the vmPFC and cerebral cortex and the risk-taking tendency after SD. The study participants were 21 healthy college students who underwent functional magnetic resonance imaging twice in the resting state, once during RW and once after 36 h of SD. The vmPFC was analyzed bilaterally for functional connectivity between the regions of interest. Correlation analysis was performed to evaluate changes in functional connectivity between the vmPFC and the cerebral cortex and risk-taking before and after SD. A single night of SD produced a definite deficit in functional connectivity between the vmPFC and thalamus bilaterally and an increase in functional connectivity between the vmPFC and dorsolateral prefrontal cortex (dlPFC) and the parietal lobe. We also found that the likelihood of risk-taking was positively correlated with increased functional connectivity between the vmPFC and dlPFC and negatively correlated with decreased functional connectivity between the vmPFC and thalamus bilaterally. These results demonstrate that lack of sleep substantially impairs functional connectivity between the vmPFC and the cerebral cortex, which in turn predicts the risk-taking behavior found after SD.

Ion concentrations in cerebrospinal fluid in wakefulness, sleep and sleep deprivation in healthy humans.

Sleep is controlled by a circadian rhythmicity, via a reduction of arousal-promoting neuromodulatory activity, and by accumulation of somnogenic factors in the interstitial fluid of the brain. Recent experiments in mice suggest that a reduced neuronal excitability caused by a reduced concentration of potassium in the brain, concomitant with an increased concentration of calcium and magnesium, constitutes an important mediator of sleep. In the present study, we examined whether such changes in ion concentrations could be detected in the cerebrospinal fluid of healthy humans. Each subject underwent cerebrospinal fluid collection at three occasions in a randomized order: at 15:00 hours-17:00 hours during waking, at 06:00 hours-07:00 hours immediately following 1 night of sleep, and at 06:00 hours-07:00 hours following 1 night of sleep deprivation. When compared with wakefulness, both sleep and sleep deprivation produced the same effect of a small (0.1 mm, about 3%), but robust and highly significant, reduction in potassium concentration. Calcium and magnesium concentrations were unchanged. Our results support a circadian modulation of neuronal excitability in the brain mediated via changes of the interstitial potassium concentration.

Effects of sleep deprivation of various durations on novelty-related object recognition memory and object location memory in mice.

Sleep is essential for important physiological functions. Impairment of learning and memory function caused by lack of sleep is a common physiological phenomenon of which underlying changes in synaptic plasticity in the hippocampus are not well understood. The possible different effects of sleep deprivation (SD) lasting for various durations on learning and memory function and hippocampal synaptic plasticity are still not completely clear. In this study, we used a modified multiple platform method (MMPM) to induce rapid eye movement SD (REM SD), lasting for 24 h, 48 h, and 72 h, separately. The novel place recognition (NPR) and novel object recognition (NOR) tasks were used to test the novelty-related object recognition memory (ORM) and object location memory (OLM) of mice. Then, hippocampal synaptic plasticity was evaluated after all behavioural experiments. The results showed that REM SD played a key role in OLM but not in ORM. Specifically, 24 h REM SD improved novelty-related OLM, accompanied by a significantly increased hippocampal synaptic plasticity, including gain of dendritic spines, increased expression of hippocampal GluA1, and enhanced long-term potentiation (LTP), whereas 48 h REM SD showed no effect on OLM or the hippocampal synaptic plasticity mentioned above; however, 72 h REM SD impaired novelty-related OLM and weakened hippocampal synaptic plasticity, including serious loss of dendritic spines, decreased expression of hippocampal GluA1, and significantly attenuated LTP. Our results suggest that REM SD of various durations has different effects on both novelty-related OLM and hippocampal synaptic plasticity.

Reciprocal regulation of chaperone-mediated autophagy and the circadian clock.

Circadian rhythms align physiological functions with the light-dark cycle through oscillatory changes in the abundance of proteins in the clock transcriptional programme. Timely removal of these proteins by different proteolytic systems is essential to circadian strength and adaptability. Here we show a functional interplay between the circadian clock and chaperone-mediated autophagy (CMA), whereby CMA contributes to the rhythmic removal of clock machinery proteins (selective chronophagy) and to the circadian remodelling of a subset of the cellular proteome. Disruption of this autophagic pathway in vivo leads to temporal shifts and amplitude changes of the clock-dependent transcriptional waves and fragmented circadian patterns, resembling those in sleep disorders and ageing. Conversely, loss of the circadian clock abolishes the rhythmicity of CMA, leading to pronounced changes in the CMA-dependent cellular proteome. Disruption of this circadian clock/CMA axis may be responsible for both pathways malfunctioning in ageing and for the subsequently pronounced proteostasis defect.

Right stellate ganglion block improves learning and memory dysfunction and hippocampal injury in rats with sleep deprivation.

BACKGROUND: Sleep deprivation (SD) often leads to complex detrimental consequences, though the mechanisms underlying these dysfunctional effects remain largely unknown. We investigated whether the right stellate ganglion block in rats can improve the spatial learning and memory dysfunction induced by sleep deprivation by alleviating the damage of hippocampus in rats. METHODS: Sixty four male Sprague Dawley rats were randomly divided into four groups: Control, SD (sleep deprivation), SGB (stellate ganglion block) and SGB + SD (stellate ganglion block+ sleep deprivation) (n = 16). The SGB and SD + SGB groups were subjected to right stellate ganglion block through posterior approach method once per day. SD and SD + SGB groups were treated with modified multi-platform water environment method for 96 h sleep deprivation in rats and their body weights were analyzed. Histopathological changes of hippocampal neurons in rats and the expression of Caspase-3 in hippocampus of rats was detected by western blotting. ELISA was used to detect the content of IL-6, IL-1 in hippocampus and serum melatonin levels. RESULTS: Compared with the group SD, the spatial learning and memory function of the group SD + SGB was improved, the weight loss was alleviated, the pathological damage of the hippocampus was reduced and the expression of IL-6, IL-1ß and Caspase-3 in the hippocampus was decreased. The content of rat serum melatonin was also increased. CONCLUSIONS: The right stellate ganglion block can improve the spatial learning and memory dysfunction of rats with sleep deprivation, and the underlying mechanism may be related to alleviating the apoptosis and inflammation of hippocampus of rats with sleep deprivation.

Hippocampal neurons' cytosolic and membrane-bound ribosomal transcript profiles are differentially regulated by learning and subsequent sleep.

The hippocampus is essential for consolidating transient experiences into long-lasting memories. Memory consolidation is facilitated by postlearning sleep, although the underlying cellular mechanisms are largely unknown. We took an unbiased approach to this question by using a mouse model of hippocampally mediated, sleep-dependent memory consolidation (contextual fear memory). Because synaptic plasticity is associated with changes to both neuronal cell membranes (e.g., receptors) and cytosol (e.g., cytoskeletal elements), we characterized how these cell compartments are affected by learning and subsequent sleep or sleep deprivation (SD). Translating ribosome affinity purification was used to profile ribosome-associated RNAs in different subcellular compartments (cytosol and membrane) and in different cell populations (whole hippocampus, Camk2a+ neurons, or highly active neurons with phosphorylated ribosomal subunit S6 [pS6+]). We examined how transcript profiles change as a function of sleep versus SD and prior learning (contextual fear conditioning; CFC). While sleep loss altered many cytosolic ribosomal transcripts, CFC altered almost none, and CFC-driven changes were occluded by subsequent SD. In striking contrast, SD altered few transcripts on membrane-bound (MB) ribosomes, while learning altered many more (including long non-coding RNAs [lncRNAs]). The cellular pathways most affected by CFC were involved in structural remodeling. Comparisons of post-CFC MB transcript profiles between sleeping and SD mice implicated changes in cellular metabolism in Camk2a+ neurons and protein synthesis in highly active pS6+ (putative "engram") neurons as biological processes disrupted by SD. These findings provide insights into how learning affects hippocampal neurons and suggest that the effects of SD on memory consolidation are cell type and subcellular compartment specific.

Sleep Disruption Worsens Seizures: Neuroinflammation as a Potential Mechanistic Link.

Sleep disturbances, such as insomnia, obstructive sleep apnea, and daytime sleepiness, are common in people diagnosed with epilepsy. These disturbances can be attributed to nocturnal seizures, psychosocial factors, and/or the use of anti-epileptic drugs with sleep-modifying side effects. Epilepsy patients with poor sleep quality have intensified seizure frequency and disease progression compared to their well-rested counterparts. A better understanding of the complex relationship between sleep and epilepsy is needed, since approximately 20% of seizures and more than 90% of sudden unexpected deaths in epilepsy occur during sleep. Emerging studies suggest that neuroinflammation, (e.g., the CNS immune response characterized by the change in expression of inflammatory mediators and glial activation) may be a potential link between sleep deprivation and seizures. Here, we review the mechanisms by which sleep deprivation induces neuroinflammation and propose that neuroinflammation synergizes with seizure activity to worsen neurodegeneration in the epileptic brain. Additionally, we highlight the relevance of sleep interventions, often overlooked by physicians, to manage seizures, prevent epilepsy-related mortality, and improve quality of life.

An altered balance of integrated and segregated brain activity is a marker of cognitive deficits following sleep deprivation.

Sleep deprivation (SD) leads to impairments in cognitive function. Here, we tested the hypothesis that cognitive changes in the sleep-deprived brain can be explained by information processing within and between large-scale cortical networks. We acquired functional magnetic resonance imaging (fMRI) scans of 20 healthy volunteers during attention and executive tasks following a regular night of sleep, a night of SD, and a recovery nap containing nonrapid eye movement (NREM) sleep. Overall, SD was associated with increased cortex-wide functional integration, driven by a rise of integration within cortical networks. The ratio of within versus between network integration in the cortex increased further in the recovery nap, suggesting that prolonged wakefulness drives the cortex towards a state resembling sleep. This balance of integration and segregation in the sleep-deprived state was tightly associated with deficits in cognitive performance. This was a distinct and better marker of cognitive impairment than conventional indicators of homeostatic sleep pressure, as well as the pronounced thalamocortical connectivity changes that occurs towards falling asleep. Importantly, restoration of the balance between segregation and integration of cortical activity was also related to performance recovery after the nap, demonstrating a bidirectional effect. These results demonstrate that intra- and interindividual differences in cortical network integration and segregation during task performance may play a critical role in vulnerability to cognitive impairment in the sleep-deprived state.

Obesity and Sleep.

Sleep is often misunderstood in its impact on many chronic diseases including obesity. Obesity and restorative sleep are intertwined processes. Poor sleep negatively affects the key hormones of weight and appetite regulation, thereby potentially increasing weight via mechanisms that increase hunger and lower metabolism, thereby making the successful treatment of obesity more difficult. Clinicians should consider a comprehensive sleep history and proper treatment or referral to a sleep specialist in conjunction with obesity treatment. Adequate restorative sleep is integral to a comprehensive obesity treatment program.

Effects of sleep habits on acute myocardial infarction risk and severity of coronary artery disease in Chinese population.

BACKGROUND: Growing evidence indicates that poor sleep harms health. Early to bed and early to rise is considered as a healthy lifestyle in Chinese population. The current study aimed to examine the effects of sleep habits on acute myocardial infarction (AMI) risk and severity of coronary artery disease (CAD) in Chinese population from two centers. METHODS: A total of 873 patients including 314 AMI cases and 559 controls were recruited from the inpatient cardiology department of the Affiliated Jiangning Hospital and the First Affiliated Hospital of Nanjing Medical University. 559 controls included 395 CAD cases and 164 non-CAD cases. We used a 17-item sleep factors questionnaire (SFQ) to evaluate sleep habits comprehensively by face-to-face interview. The severity of CAD was assessed by Gensini score in AMI and CAD groups. The effects of sleep factors on AMI risk and Gensini score were examined by unconditional logistic regression. RESULTS: After mutually adjustment for other sleep factors and demographic characteristics, the timing of sleep (24:00 and after) and morning waking (after 7:00) and sleep duration (< 6 h) were associated with increased risk of AMI (OR = 4.005, P < 0.001, OR = 2.544, P = 0.011 and OR = 2.968, P < 0.001, respectively). Lower level of light exposure at night was correlated with reduced risk of AMI (OR = 0.243, P = 0.009). In subgroup analysis by age, both late sleep timing and short sleep duration were associated with increased risk of AMI regardless of age. In subjects with age ≤ 65 years, daytime napping was related to reduced risk of AMI (OR = 0.645, P = 0.046). In subjects with age > 65 years, the frequency of night-time waking (3 times) was associated with increased risk of AMI (OR = 3.467, P = 0.035). Short sleep duration was correlated with increased risk of high Gensini score (OR = 2.374, P < 0.001). CONCLUSION: Sleep insufficiency is an important risk factor both for AMI risk and CAD severity. Late sleeping is also associated with increased risk of AMI. In young and middle-aged people, regular naps may have a protective effect.

Sleep deprivation affects gait control.

Different levels of sleep restriction affect human performance in multiple aspects. However, it is unclear how sleep deprivation affects gait control. We applied a paced gait paradigm that included subliminal rhythm changes to analyze the effects of different sleep restriction levels (acute, chronic and control) on performance. Acute sleep deprivation (one night) group exhibited impaired performance in the sensorimotor synchronization gait protocol, such as a decrease in the Period Error between the footfalls and the auditory stimulus as well as missing more frequently the auditory cues. The group with chronic sleep restriction also underperformed when compared to the control group with a tendency to a late footfall with respect to the RAC sound. Our results suggest that partial or total sleep deprivation leads to a decrease in the performance in the sensorimotor control of gait. The superior performance of the chronic sleep group when compared to the acute group suggests that there is a compensatory mechanism that helps to improve motor performance.

A MULTIFACTORIAL APPROACH FOR IMPROVING THE SURGICAL PERFORMANCE OF NOVICE VITREORETINAL SURGEONS.

PURPOSE: To quantitatively analyze and compare the novice vitreoretinal surgeons' performance after various types of external exposures. METHODS: This prospective, self-controlled, cross-sectional study included 15 vitreoretinal fellows with less than 2 years of experience. Surgical performance was assessed using the Eyesi simulator after each exposure: Day 1, placebo, 2.5, and 5 mg/kg caffeine; Day 2, placebo, 0.2, and 0.6 mg/kg propranolol; Day 3, baseline simulation, breathalyzer reading of 0.06% to 0.10% and 0.11% to 0.15% blood alcohol concentration; Day 4, baseline simulation, push-up sets with 50% and 85% repetition maximum; Day 5, 3-hour sleep deprivation. Eyesi-generated total scores were the main outcome measured (0-700, worst to best). RESULTS: Performances worsened after increasing alcohol exposure based on the total score (χ2 = 7; degrees of freedom = 2; P = 0.03). Blood alcohol concentration 0.06% to 0.10% and 0.11% to 0.15% was associated with diminished performance compared with improvements after propranolol 0.6 and 0.2 mg/kg, respectively (∆1 = -22 vs. ∆2 = +13; P = 0.02; ∆1 = -43 vs. ∆2 = +23; P = 0.01). Propranolol 0.6 mg/kg was positively associated with the total score, compared with deterioration after 2.5 mg/kg caffeine (∆1 = +7 vs. ∆2 = -13; P = 0.03). CONCLUSION: Surgical performance diminished dose dependently after alcohol. Caffeine 2.5 mg/kg was negatively associated with dexterity, and performance improved after 0.2 mg/kg propranolol. No changes occurred after short-term exercise or acute 3-hour sleep deprivation.

Protocol for Drosophila sleep deprivation using single-chip board.

Sleep behavior is characterized by long-term quiescence and increased arousal threshold, and it is homeostatically regulated. The sleep rebound after deprivation is utilized to verify the abilities to maintain homeostasis. This protocol shows how to build a programmed mechanic oscillation system and detailed procedures to conduct sleep deprivation in Drosophila. This deprivation system is featured by its programming flexibility. The knowledge of electronic circuits and a certain level of programming are both required to fulfill this protocol. For complete details on the use and execution of this protocol, please refer to Jin et al. (2021).