Return-to-work rates and predictors of absence duration after COVID-19 over the course of the pandemic.

OBJECTIVES: The aim of this study was to evaluate employee return-to-work (RTW) rates and examine predictors of absence duration after COVID-19. RTW rates were referenced against RTW rates after absence due to flu-like symptoms and assessed over the course of the pandemic. METHODS: Routinely collected data from a nationally operating Dutch occupational health service was used. The data were retrieved from employees who reported sick due to COVID-19 (N=30 396) or flu-like symptoms (N=15 862). Data consisted of responses to a triage survey combined with longitudinal register-based information on sickness absence. RTW rates after COVID-19 were evaluated through Kaplan-Meier estimates and compared to RTW rates for flu-like symptoms, and between three periods with different dominant virus variants. Predictors for absence duration were examined through Cox proportional hazards models. RESULTS: RTW after COVID-19 was found to be notably later than after flu-like symptoms (median RTW=10 versus 6 days, respectively). On average, 5.5% of employees who contracted COVID-19 were absent for over 12 weeks. Time-to-RTW shortened as different virus variants became dominant over time. The main predictors contributing to later RTW were older age, female sex, belonging to a risk group, and the symptoms shortness of breath and fatigue. CONCLUSIONS: Estimates of the RTW rate after COVID-19 and identification of predictors may aid healthcare professionals in gaining insight into variations in the disease course and rehabilitation process. The present findings can help employers and policy-makers grasp the impact of COVID-19 on the workplace.

Reactive and proactive cognitive control as underlying processes of number processing in children.

Cognitive control is crucial to resolve conflict in tasks such as the flanker task. Reactive control is used when conflict is rare, whereas proactive control is more efficient in situations where conflict is frequent. Macizo and Herrera (Psychological Research, 2013, Vol. 77, pp. 651-658) found that these two control processes can also underlie two-digit number comparison in adults. Specifically, they observed that the unit-decade compatibility effect decreased in a block containing many conflict trials as compared with a block containing few conflict trials (i.e., a list-wide proportion congruency effect). In the current study, we assessed whether this finding also applies to children (7-, 9-, and 11-year-olds). Participants performed a flanker task and a two-digit number comparison task. In both tasks, the proportion of conflict was manipulated (80% vs. 20%). Results from the flanker task showed a typical list-wide proportion congruency effect in reaction times in all participating age groups. In the number comparison task, we observed list-wide proportion congruency effects in both reaction times and error rates, which did not interact with age. Our findings support the assumption that children as young as 7 years can effectively use proactive and reactive control strategies. We showed that this effect is not limited to standardized artificial laboratory tasks, such as the flanker task, but also underlies more daily life tasks, such as the processing of Arabic numbers.

Embodying Stressful Events: No Difference in Subjective Arousal and Neural Correlates Related to Immersion, Interoception, and Embodied Mentalization.

Repetitive thought about oneself, including one's emotions, can lead to both adaptive and maladaptive effects. Construal level of repetitive self-referential thought might moderate this. During interoception, which engages areas such as the insula, the anterior and/or posterior cingulate cortex (PCC) and the somatosensory cortex, concrete low level construal self-referential thought is applied, which has been shown to lead to more positive emotions after upsetting events. Contrarily, during immersion, related to neural activity in the default mode network (DMN), abstract high level construal self-referential thought is applied, which is linked to depression. The current study investigated whether the integration of concrete and abstract self-referential thought by means of embodied mentalization leads to less subjective arousal, decreased DMN activity and increased somatosensory activity as compared to immersion, and to more DMN activity as compared to interoception. In the fMRI scanner, participants imagined stressful events while adopting immersion, interoception or embodied mentalization. After each imagined stressful event, participants rated their subjective arousal and how difficult it was to apply the mode of self-referential thought. Results showed that participants felt that immersion was easier to apply than embodied mentalization. However, no differences in subjective arousal or neural activity were found between immersion, interoception and embodied mentalization. Possible reasons for this lack of significant differences are discussed.

The Aha! moment: Is insight a different form of problem solving?

In everyday life, we mainly solve problems with a conscious solution search (non-insight). However, sometimes a perplexing problem is resolved by a quantum leap in understanding. This phenomenon is known as the Aha! experience (insight). Although insight has a distinct phenomenological and behavioral signature, its driving mechanism remains debated. Weisberg (2015) proposed an integrated theory of insight arguing that insight, like non-insight, mainly depends on conscious, cognitive operations with restructuring as a distinguishing feature of insight. However, only if those operations lead to an impasse, insight is achieved through unconscious processes. We assessed some of the premises of this theory by asking participants (N = 42) to solve 70 word puzzles (CRAT) that can either be solved with insight or non-insight. For each puzzle, participants indicated word puzzle difficulty, solution confidence, solution suddenness, and the experiences of impasse and restructuring. As expected, participants reported higher suddenness of and confidence in insight solutions than non-insightful ones. Surprisingly, we could not corroborate the otherwise consistently reported higher solution accuracy and faster solution speed for insight. Crucially, as suggested by the integrated theory of insight, impasse was not a prerequisite for insight to occur. Although restructuring, indeed, preceded insight solutions more often, it seemed a more general problem-solving skill also applied for non-insight solutions. Moreover, early on, participants reported an increased experience of problem difficulty for puzzles later solved with insight. This ability to report on the solution search of insight demonstrates that, as proposed by the theory, insight involves conscious, cognitive operations.

Cognitive Effort Modulates Connectivity between Dorsal Anterior Cingulate Cortex and Task-Relevant Cortical Areas.

Investment of cognitive effort is required in everyday life and has received ample attention in recent neurocognitive frameworks. The neural mechanism of effort investment is thought to be structured hierarchically, with dorsal anterior cingulate cortex (dACC) at the highest level, recruiting task-specific upstream areas. In the current fMRI study, we tested whether dACC is generally active when effort demand is high across tasks with different stimuli, and whether connectivity between dACC and task-specific areas is increased depending on the task requirements and effort level at hand. For that purpose, a perceptual detection task was administered that required male and female human participants to detect either a face or a house in a noisy image. Effort demand was manipulated by adding little (low effort) or much (high effort) noise to the images. Results showed a network of dACC, anterior insula (AI), and intraparietal sulcus (IPS) to be more active when effort demand was high, independent of the performed task (face or house detection). Importantly, effort demand modulated functional connectivity between dACC and face-responsive or house-responsive perceptual areas, depending on the task at hand. This shows that dACC, AI, and IPS constitute a general effort-responsive network and suggests that the neural implementation of cognitive effort involves dACC-initiated sensitization of task-relevant areas.SIGNIFICANCE STATEMENT Although cognitive effort is generally perceived as aversive, its investment is inevitable when navigating an increasingly complex society. In this study, we demonstrate how the human brain tailors the implementation of effort to the requirements of the task at hand. We show increased effort-related activity in a network of brain areas consisting of dorsal anterior cingulate cortex (dACC), anterior insula, and intraparietal sulcus, independent of task specifics. Crucially, we also show that effort-induced functional connectivity between dACC and task-relevant areas tracks specific task demands. These results demonstrate how brain regions specialized to solve a task may be energized by dACC when effort demand is high.

Context-dependent modulation of cognitive control involves different temporal profiles of fronto-parietal activity.

To efficiently deal with quickly changing task demands, we often need to organize our behaviour on different time scales. For example, to ignore irrelevant and select relevant information, cognitive control might be applied in reactive (short time scale) or proactive (long time scale) mode. These two control modes play a pivotal role in cognitive-neuroscientific theorizing but the temporal dissociation of the underlying neural mechanisms is not well established empirically. In this fMRI study, a cognitive control task was administered in contexts with mainly congruent (MC) and mainly incongruent (MI) trials to induce reactive and proactive control, respectively. Based on behavioural profiles, we expected cognitive control in the MC context to be characterized by transient activity (measured on-trial) in task-relevant areas. In the MI context, cognitive control was expected to be reflected in sustained activity (measured in the intertrial interval) in similar or different areas. Results show that in the MC context, on-trial transient activity (incongruent - congruent trials) was increased in fronto-parietal areas, compared to the MI context. These areas included dorsolateral prefrontal cortex (dlPFC) and intraparietal sulcus (IPS). In the MI context, sustained activity in similar fronto-parietal areas during the intertrial interval was increased, compared to the MC context. These results illuminate how context-dependent reactive and proactive control subtend the same brain areas but operate on different time scales.

Persistent modification of cognitive control through attention training.

An important aspect of cognitive control is to direct attention towards relevant information and away from distracting information. This attentional modulation is at the core of several influential frameworks, but its trainability and generalisability remain unclear. To address this issue, two groups of subjects were invited to the lab on three consecutive days. On Day 2, they performed an arrow priming task which trained them to adopt an attentional bias towards (prime-attended group) or away from (prime-diverted group) a potentially conflicting prime. Direct generalisation of the attention training was measured by assessing task performance on the same task without the attentional manipulation directly after training (Day 2) and the next day (Day 3), and comparing it to baseline (Day 1). Performance on this direct transfer task showed a difference in attentional modulation between groups directly after training that persisted the next day. No cross-task generalisation was found to two other tasks that were closely or more remotely related to the trained task. Together, these results are in accordance with cognitive control frameworks that limit attentional modulation to the specific features of the trained task.

Ultra-short term heart rate variability as a tool to assess changes in valence.

Heart rate variability (HRV) is an index that has been extensively used in fields such as clinical cardiology, psychiatry, and psychology to assess affective experiences. Although traditionally The European Society of Cardiology and The North American Society of Pacing and Electrophysiology recommended to use either a recording length of 24-h (long-term) or five minutes (short-term), recent advances in the field have suggested the use of ultra-short term (<5 min) HRV measurements. In this study, we investigated whether ultra-short term HRV measurements can be used to investigate the temporal dynamics of experimentally induced emotions using pictures from the International Affective Picture System. We took electrocardiogram recordings from thirty-nine participants, and analyzed the root mean square of the successive differences of the R-R interval using a thirty-second moving window. No significant differences in HRV during positive and negative emotion induction were found. These results call into question the use of ultra-short term HRV as a tool for psychologists to measure changes in valence in affective studies.

Beyond trial-by-trial adaptation: A quantification of the time scale of cognitive control.

The idea that adaptation to stimulus or response conflict can operate over different time scales takes a prominent position in various theories and models of cognitive control. The mechanisms underlying temporal variations in control are nevertheless poorly understood, which is partly due to a lack of appropriate empirical measures. Inspired by reinforcement learning models, we developed a method to quantify the time scale of control behaviorally, by computing trial-by-trial effects that go beyond the preceding trial. Briefly, we extended the congruency sequence effect from 1 trial to multiple trials into the past and quantified the influence of previous trials on current-trial performance as a function of trial distance. The rate at which this influence changes across trials was taken as a measure of the time scale of control. We applied the method to a flanker task with different conflict frequencies and volatility. Results showed that the time scale of control was smaller in rare-conflict and volatile contexts, compared to frequent-conflict and neutral contexts. This is in agreement with theories differentiating transient from sustained control. The method offers new opportunities to reveal temporal differences in control modes and can easily be applied to various empirical paradigms. (PsycINFO Database Record

About the Distinction between Working Memory and Short-Term Memory.

The theoretical concepts short-term memory (STM) and working memory (WM) have been used to refer to the maintenance and the maintenance plus manipulation of information, respectively. Although they are conceptually different, the use of the terms STM and WM in literature is not always strict. STM and WM are different theoretical concepts that are assumed to reflect different cognitive functions. However, correlational studies have not been able to separate both constructs consistently and there is evidence for a large or even complete overlap. The emerging view from neurobiological studies is partly different, although there are conceptual problems troubling the interpretation of findings. In this regard, there is a crucial role for the tasks that are used to measure STM or WM (simple and complex span tasks, respectively) and for the cognitive load reflected by factors like attention and processing speed that may covary between and within these tasks. These conceptual issues are discussed based on several abstract models for the relation between STM and WM.