Fatigue-Related Effects in the Process of Task Interruption on Working Memory

Intertemporal Decision-making and Risk Decision-making Among Habitual Nappers Under Nap Sleep Restriction: A Study from ERP and Time-frequency

Sleep restriction affects people's decision-making behavior. Nap restriction is a vital subtopic within sleep restriction research. In this study, we used EEG to investigate the impact of nap sleep restriction on intertemporal decision-making (Study 1) and decision-making across risky outcomes (Study 2) from ERP and time-frequency perspectives. Study 1 found that habitual nappers restricting their naps felt more inclined to choose immediate, small rewards over delayed, large rewards in an intertemporal decision-making task. P200s, P300s, and LPP in our nap-restriction group were significantly higher than those in the normal nap group. Time-frequency results showed that the delta band (1 ~ 4 Hz) power of the restricted nap group was significantly higher than that of the normal nap group. In Study 2, the nap-restriction group was more likely to choose risky options. P200s, N2s, and P300s in the nap deprivation group were significantly higher than in the normal nap group. Time-frequency results also found that the beta band (11 ~ 15 Hz) power of the restricted nap group was significantly lower than that of the normal nap group. The habitual nappers became more impulsive after nap restriction and evinced altered perceptions of time. The time cost of the LL (larger-later) option was perceived to be too high when making intertemporal decisions, and their expectation of reward heightened when making risky decisions-believing that they had a higher probability of receiving a reward. This study provided electrophysiological evidence for the dynamic processing of intertemporal decision-making, risky decision-making, and the characteristics of nerve concussions for habitual nappers.

Interruption science as a research field: Towards a taxonomy of interruptions as a foundation for the field

Interruptions have become ubiquitous in both our personal and professional lives. Accordingly, research on interruptions has also increased steadily over time, and research published in various scientific disciplines has produced different perspectives, fundamental ideas, and conceptualizations of interruptions. However, the current state of research hampers a comprehensive overview of the concept of interruption, predominantly due to the fragmented nature of the existing literature. Reflecting on its genesis in the 1920s and the longstanding research on interruptions, along with recent technological, behavioral, and organizational developments, this paper provides a comprehensive interdisciplinary overview of the various attributes of an interruption, which facilitates the establishment of interruption science as an interdisciplinary research field in the scientific landscape. To obtain an overview of the different interruption attributes, we conducted a systematic literature review with the goal of classifying interruptions. The outcome of our research process is a taxonomy of interruptions, constituting an important foundation for the field. Based on the taxonomy, we also present possible avenues for future research.

The rat Lux Actuating Search Task (LAST) and effects of sleep deprivation on task reversal performance

Sleep deprivation (SD) causes significant deficits in multiple aspects of cognition, including sustained attention and working memory. Investigating the neural processes underpinning these cognitive losses has proven challenging due to the confounds of current animal tasks; many employ appetitive or aversive stimuli to motivate behavior, while others lack task complexity that translates to human studies of executive function. We established the Lux Actuating Search Task (LAST) to circumvent these issues. The LAST is performed in a circular, open-field arena that requires rats to find an unmarked, quasi-randomly positioned target. Constant low-level floor vibrations motivate ambulation, while light intensity (determined by the rodent's proximity to the target destination) provides continuous visual feedback. The task has two paradigms that differ based on the relationship between the light intensity and target proximity: the Low Lux Target (LLT) paradigm and the High Lux Target paradigm (HLT). In this study, on days 1–6, the rats completed nine trials per day on one of the two paradigms. On day 7, the rats were either sleep deprived by gentle handling or were left undisturbed before undertaking the opposite (reversal) paradigm on days 7–9. Our results showed that SD significantly impeded the ability of Long Evans rats to learn the reversal paradigm, as indicated by increased times to target and increased failure percentages compared to rats whose sleep was undisturbed. Rats also showed reduced learning with the HLT paradigm, as the initial task or as the reversal task, likely due to the rodents' photophobia limiting their motivation to navigate toward a bright light, which is required to succeed.

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A continuous feedback paradigm examining the effects of sleep loss on cognitive flexibility in rats is introduced.

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Floor vibrations motivate and variable light intensity directs navigation to an unmarked location in an open field arena.

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The reversal of light intensity cues from light to dark and vice versa is disrupted by sleep deprivation.

The neuroelectrophysiological and behavioral effects of transcranial direct current stimulation on executive vigilance under a continuous monotonous condition

A prolonged period of vigilance task will lead to vigilance decrement and a drop in cognitive efficiency. Although transcranial direct current stimulation (tDCS) can be used to improve cognitive performance following vigilance decrement, the findings in this area of study are inconsistent. This study aims to identify the neuroelectrophysiological and behavioral effects of tDCS over the left dorsolateral prefrontal cortex (DLPFC) on executive vigilance under a continuous monotonous condition. We recruited 29 participants who randomly received 30 min active or sham tDCS before the vigilance task (anode electrode at the left DLPFC, cathode electrode at the right supraorbital area). Participants completed four sessions of vigilance task and five sessions of self-report sleepiness, Oddball task, and Go/Nogo task, for a total of about 5 h. EEG was acquired in real-time throughout the experiment. Repeated measures of ANOVA were utilized to analyze the evolution of each metric with task-on-time. The results demonstrated that subjective arousal state, vigilance performance, event-related potentials (ERPs), and EEG power were significantly affected by time on task. Brain stimulation did not significantly affect the evolution of subjective and objective executive vigilance performance, but significantly modulated spontaneous activity in the alpha and beta bands across the entire brain. The continuous enhancement of the prefrontal cortex increased P2 amplitude for the Oddball task, which was associated with the enhancement of the early stage of information processing. P3 amplitude had a temporary enhancement effect, which significantly decreased following a cognitive fatigue. tDCS had a continuous enhancement effect on N2 amplitude for the Go/Nogo task, which was associated with the enhanced inhibition of distracting stimuli. Together, the current data suggest that anodal tDCS over left DLPFC possibly enhances the early stage of relevant information processing and the inhibitory control of distracting stimuli during a continuous and monotonous vigilance task.