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Initiated by a long stay of Valérie Doyère in the laboratory of Joseph LeDoux, a Franco-American collaborative group was formed around the topic of emotion and time perception in a comparative perspective between humans and non-human animals. Here, we discuss results from our studies on the mechanisms underlying time distortion under 2 conditions, timing of a threatening stimulus and timing of a neutral stimulus in the context of fear, with insights from neurodevelopment. Although the type of temporal distortion depends on the experimental situations, in both humans and rodents a high-arousal emotion automatically triggers acceleration of an "internal clock" system, an effect that may rely on the early maturing amygdala. Our studies, particularly in humans, also point to the role of attention and self-awareness in regulating the effect of fear on timing, relying on the prefrontal cortex, a late maturing structure. Thus, in line with LeDoux, while the amygdala may process all characteristics of events (including time) necessary to quickly trigger appropriate survival behaviors, some type of time distortions may rely on higher-order processing, some specific to humans. The extent of the network underlying threat-related time distortions remains to be explored, with species comparisons being a promising means of investigation., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

In accordance with Bud (A.D.) Craig's theories, we maintain that ascending physiological signals in their temporal dynamics are a necessary prerequisite for human time judgments. Functional neuroimaging and psychophysiological evidence have increasingly demonstrated that the subjective judgment of time is based on the physical and emotional self. The psychological literature reveals how emotions and related body feelings shape subjective time. Empirical studies of altered states of consciousness, namely meditative states, are also of prime interest as the perception of the physical state is strongly modulated and thereby affects the subjective experience of time. Our conclusion is that the sense of time is strongly embodied., (© 2024. The Author(s), under exclusive license to Springer Nature Switzerland AG.)

Affiliation is a basic human need, especially during difficult times. To what extent did the need to affiliate limit our capacity to abide by health guidelines, in particular regarding social distancing, during the COVID-19 pandemic? We investigated this issue using questionnaire data from two samples of the French population collected during the first French lockdown (April-May 2020). We found that in men, higher social comparison orientation (sensitivity to the needs of others and inclination to help) and higher perceived threat increased the frequency of reported affiliative activities. At the same time, men's reported affiliative activities were associated with a lower reported intention to abide by lockdown and protective measures and lower levels of reported compliance. This pattern was not found in women. The women in our samples, as has been observed elsewhere, were largely compliant, potentially precluding any effects of affiliative needs. Basic though they may seem, affiliative needs and reported affiliative activities may have played a significant role in the implementation of sanitary guidelines during the COVID-19 pandemic., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Dezecache et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

The ability to organize and memorize the unfolding of events over time is a fundamental feature of cognition, which develops concurrently with the maturation of the brain. Nonetheless, how temporal processing evolves across the lifetime as well as the links with the underlying neural substrates remains unclear. Here, we intend to retrace the main developmental stages of brain structure, function, and cognition linked to the emergence of timing abilities. This neurodevelopmental perspective aims to untangle the puzzling trajectory of temporal processing aspects across the lifetime, paving the way to novel neuropsychological assessments and cognitive rehabilitation strategies., (© 2024. The Author(s).)

The aim of this study was to systematically examine the effect of awe-inducing stimuli on the judgment of time. Three experiments were conducted using temporal bisection tasks in which participants viewed awe-inducing and no awe-inducing images presented for different durations and were asked to judge whether their duration was similar to a short or long anchor duration. Images of panoramic landscapes and images of the faces of well-known and admired people were used in experiments 1 and 2, respectively. In experiment 3, they did not judge the duration of the images, but that of a neutral stimulus occurring during the presentation of images. In each experiment, participants rated the awe-inducing and no-awe-inducing images according to their components: admiration, beauty, awe, emotional valence, arousal, symbolic self-size, and full-body self-size. Results consistently showed significant time distortions when participants viewed the different awe-inducing images compared to the no-awe images, although the effect was weaker for the images of faces than for those of landscapes. Time distortion took the form of temporal lengthening in Experiments 1 and 2 and shortening in Experiment 3. These different temporal distortions are consistent with attention effects due to awe-inducing stimuli which capture attention to the detriment of time processing., Competing Interests: Declaration of competing interest None., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

A central question in understanding cognition and pathology-related cognitive changes is how we process time. However, time processing difficulties across several neurological and psychiatric conditions remain seldom investigated. The aim of this review is to develop a unifying taxonomy of time processing, and a neuropsychological perspective on temporal difficulties. Four main temporal judgments are discussed: duration processing, simultaneity and synchrony, passage of time, and mental time travel. We present an integrated theoretical framework of timing difficulties across psychiatric and neurological conditions based on selected patient populations. This framework provides new mechanistic insights on both (a) the processes involved in each temporal judgement, and (b) temporal difficulties across pathologies. By identifying underlying transdiagnostic time-processing mechanisms, this framework opens fruitful avenues for future research., Competing Interests: Declaration of Competing Interest The authors declare no competing interests., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

In this French longitudinal study, we assessed judgment of the passage of time in current life and the predictors of this judgment 2 years after the onset of the COVID-19 pandemic, i.e., at a time when there was no lockdown and no protective measures. We then compared these measures with the same participants' passage-of-time judgments assessed during each of the past three French lockdowns. We also assessed their memory representations of the passage of time in the past, i.e., for the various lockdowns. The results showed the persistence of the feeling of time slowing down outside of lockdown. However, this was no longer linked to external factors (lack of activity, disruption of everyday routines) as found in the previous studies conducted during the lockdowns, but to an individual internal factor, namely a high level of depression in the general population. Moreover, the results revealed that the experience of the passage of time for the past lockdowns was compressed in memory, being judged to be faster than it actually was. This time compression tended to be greater in depressed people. It was also associated with a positive bias for all the other examined factors (e.g., sleep quality, life routine, boredom, happiness). We assumed that this time compression would be related to processes involved in the recall of unfolding events, with certain moments being omitted or forgotten during recall, as well as to the process of reconstruction in autobiographical memory. Our study therefore shows the long-lasting effect of lockdowns on mental health of the general population, which was expressed by the persistent feeling of a slowing down of time. It is therefore necessary to take care of this psychologically fragile population and to avoid further lockdowns in response to a new health crisis, that they cannot cope with., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Droit-Volet et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

When people say that time is passing faster or slower, they are referring to the clock time. What exactly is the role of this reference to clock time in the awareness of the passage of time? Three experiments were conducted to examine this question. In Experiment 1, participants performed an easy and a difficult task in a condition with or without an external clock. In Experiment 2, the external clock was introduced after several trials of the easy task performed by the same participants. In Experiment 3, the speed of the clock hands was manipulated. Eye movements towards the clock were recorded by an eye tracker. The results showed that time was judged to pass faster with the external clock, thus reducing the distortion of the sense of time. Indeed, participants noticed that time passed faster than they initially thought. However, our results also showed that this was an occasional and short-lived adjustment of subjective time to objective time, with a greater acceleration in the presence of the fast clock. Indeed, the clock quickly lost its effect after a few trials, the feeling of the passage remaining based on the emotion felt, i.e., the boredom felt in the easy task. Our experiments thus showed that the feeling of the passage of time is primarily grounded in the emotional affect experienced (Embodiment), and that knowledge of clock time had only a small and transient corrective effect., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

The present study aimed to evaluate the effects of age and sex on the rating of perceived exertion (RPE) during high-intensity exercise and determine whether mechanical and physiological parameters could be predictors of RPE during childhood and adolescence. Forty-three boys and 36 girls performed a 60-s all-out test on a rowing ergometer and were categorized by age group (10.0-11.9; 12.0-13.9; 14.0-15.9; 16.0-17.9 years) and sex. Ratings of perceived exertion were assessed using the 6-20 RPE and CR-10 scales and analyzed with respect to mechanical work rate (W tot ), post-exercise peak blood lactate concentration ([La] peak ), and peak minute ventilation (V̇E peak ). Multilevel regression modeling revealed a significant influence of W tot , [La] peak and V̇E peak on 6-20 RPE and CR-10 scores (r 2  = .34 and .36, p < .001, respectively). However, while boys perceived high-intensity exercise as being subjectively more difficult than girls at all ages (p < .05) except 12.0-13.9 years, significant higher mechanical work rate and greater associated metabolic responses in boys than girls were only found from the age of 14 years (W tot and V̇E peak ) or 16 years ([La] peak ), suggesting that the association between RPE and mechanical/physiological parameters could not be held before the age of 12 years. To conclude, RPE increased with increasing age, with boys exhibiting higher scores than girls at all ages except 12.0-13.9 years. This finding is probably explained by the higher W tot and greater concomitant metabolic responses in boys at the time of puberty. However, other factors should be considered at least in children before the age of 12 years., (© 2023 Society for Psychophysiological Research.)

This study examined the relationships between the awareness of the speed of the passage of time, the judgment of durations and experiential factors in children aged 4-9 years. They were asked to judge the duration and the speed of the passage of time for different intervals (second and minutes), and to rate their feelings (arousal, happiness, sadness, and task difficulty) during each interval. The results indicated that 8-9-year-olds' judgment of the passage of time is extremely flexible and context-dependent, representing the duration and/or the individual changes in subjective experience (emotion). In contrast, young children's judgment of the passage of time was not related to duration. However, their judgments were not given randomly. They judged that time passed more quickly when they felt happier and more alert. The passage-of-time judgment was therefore initially grounded in emotional and sensory-motor experience, i.e., in their perception of changes (acceleration and deceleration) in self-movement (successions of states and their extension). Therefore, duration judgment and passage-of-time judgment initially develop separately and are later combined when children understand the logical link between speed and duration., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Martinelli and Droit-Volet.)

The aim of this study in the field of computational neurosciences was to simulate and predict inter-individual variability in time judgements with different neuropsychological properties. We propose and test a Simple Recurrent Neural Network-based clock model that is able to account for inter-individual variability in time judgment by adding four new components into the clock system: the first relates to the plasticity of the neural system, the second to the attention allocated to time, the third to the memory of duration, and the fourth to the learning of duration by iteration. A simulation with this model explored its fit with participants' time estimates in a temporal reproduction task undertaken by both children and adults, whose varied cognitive abilities were assessed with neuropsychological tests. The simulation successfully predicted 90% of temporal errors. Our Cognitive and Plastic RNN-Clock model (CP-RNN-Clock), that takes into account the interference arising from a clock system grounded in cognition, was thus validated., (© 2023. The Author(s).)

The study investigated participants' verbal duration judgment and judgment of passage of time (PoT) when presented with an image for a few seconds (20 to 45 s) or minutes (80 to 180 s) with prospective and retrospective temporal judgment instruction, with their level of attention devoted to time tested. Their self-reported levels of emotion and attention were also assessed, as well as their individual impulsivity traits. Structural equation analyses showed that the best predictor of PoT judgment was emotion (boredom) regardless of duration range. For duration judgment, the best predictor for short durations was attention-related factors. However, for long durations, these factors ceased to be significant and were replaced by emotion, in the same way as for the PoT judgment. Indeed, these analyses suggested that duration judgment and PoT judgment were related for long durations of more than one minute, whereas they were not related for short durations of a few seconds., (© 2022. The Author(s).)

The aim of this study was to examine the factors that explain variations in the conscious experience of time. The level of difficulty of the task, emotional valence and duration of stimuli were tested in three different experiments with two ranges of durations, one of seconds and the other one of minutes. The results showed that the passage of time was judged faster with durations in the seconds than in the minutes range. However, for all duration values, each change in the features of the task produced changes in the judgment of the passage of time. The subjective feeling of an acceleration of the passage of time, therefore, increased linearly with the increase in the level of difficulty of the task and with the positive valence of the emotional stimuli. It also varied linearly with the length of real time, increasing in the same proportion as the decrease in stimulus duration, regardless of the associated range (seconds or minutes). Our theory is that the judgment of the passage of time might be a generic way of describing the most salient internal or external contextual changes experienced., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The aim of the present study was to test how the perception of an emotional stimulus colors the temporal context of judgment and modifies the participant's perception of the current neutral duration. Participants were given two ready-set-go tasks consisting of a distribution of short (0.5-0.9 s) or long sample intervals (0.9-1.3 s) with an overlapping 0.9-s interval. Additional intervals were introduced in the temporal distribution. These were neutral for the two temporal tasks in a control condition and emotional for the short, but not the long temporal task in an emotion condition. The results indicated a replication of a kind of Vierordt's law in the control condition, i.e., the temporal judgment toward the mean of the distribution of sample intervals (central tendency effect). However, there was a shift in the central tendency effect in the emotion condition indicating a general bias in the form of an overestimation of current intervals linked to the presence of a few emotional stimuli among the previous intervals. This finding is entirely consistent with timing mechanisms driven by prior duration context, particularly experience of prior emotional duration., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Droit-Volet and Gil.)

Tool behavior might be based on two strategies associated with specific cognitive mechanisms: cued-learning and technical-reasoning strategies. We aimed to explore whether these strategies coexist in young children and whether they are manifest differently through development. We presented 216 3- to 9-year-olds with a vertical maze task consisting in moving a ball from the top to the bottom of a maze. Two tool-use/mechanical actions were possible: rotating action and sliding action. Three conditions were tested, each focused on a different strategy. In the Opaque-Cue condition (cued-learning strategy), children could not see the mechanical action of each tool. Nevertheless, a cue was provided according to the tool needed to solve the problem. In the Transparent-No Cue condition (technical-reasoning strategy), no cue was presented. However, children could see the mechanical actions associated with each tool. In the Transparent-Cue condition (cued-learning and/or technical-reasoning strategies) children saw both the mechanical actions and the cues. Results indicated that the Opaque-Cue and Transparent-Cue conditions were easier than the Transparent-No-Cue condition in all children. These findings stress that children can use either cued learning or technical reasoning to use tools, according to the available information. The behavioral pattern observed in the Transparent-Cue condition suggests that children might be inclined to use technical reasoning even when the task can be solved through cued learning., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Children from 5 to 8 years of age, as well as adults, performed a temporal reproduction task in both a solo-timing condition and a multi-timing condition, with different durations presented simultaneously. In the multi-timing condition, all durations were processed because the participants did not know in advance which stimulus needed to be judged. In a first experiment, two or three durations were presented with a synchrony of their onset. In a second experiment, two durations were presented simultaneously with asynchrony of their offset, different lengths of the concurrent duration, and different presentation orders. In addition, the participants' cognitive abilities in terms of selective attention, as well as short-term and working memory, were assessed with different neuropsychological tests. The results of both experiments showed that children and adults alike were able to process multiple durations simultaneously. However, the simultaneous presentation of different durations generated a temporal interference effect in children and adults, resulting in longer and more variable time estimates. This temporal interference effect was nevertheless higher in children due to their limited attention capacities. Therefore, a developmental improvement in the ability to process different durations simultaneously is related to the cognitive development of attention capacities., (Copyright © 2021 Elsevier Inc. All rights reserved.)

The home confinement imposed on people to fight the COVID-19 pandemic interrupted the flow of time by disrupting daily life, making them feel that time was passing slowly. The aim of this longitudinal study was to evaluate the evolution over time of this subjective experience of time and its significant predictors (boredom, decreased happiness, life rhythm, and sleep quality). Twso samples of French participants were followed up: the first for several weeks during the first lockdown (April 2020) and then 1year later (April 2021; Study 1), and the second during the first lockdown (April 2020) and then 6months (November 2020) and 1year later (April 2021; Study 2). Our study shows that the French participants have the feeling that time has passed slowly since the beginning of the first lockdown and that it has not resumed its normal course. This is explained by a persistent feeling of boredom characteristic of a depressive state that has taken hold in the population. The findings therefore suggest that the repeated contexts of confinement did not contribute to re-establishing a normal perception of time, to which a subjective acceleration of time would have testified., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Droit-Volet, Martinelli, Chevalère, Belletier, Dezecache, Gil and Huguet.)

This study investigated the difficulties experienced by people suffering from depression in coping with the stressful context of the COVID-19 pandemic and the lockdown. Two large samples of the French population were classified on the basis of their depressive symptoms and completed an online questionnaire on their emotions and their behaviors during the lockdown. Results showed that, compared to participants with no or mild mental health-related symptoms, participants with moderate to severe depressive symptoms suffered from greater psychological effects of the pandemic and the lockdown (fear, anxiety, sadness, sleep quality, loss of daily routine). However, health risk behaviors (smoking, drinking, non-compliance with lockdown and barrier gestures) and perceived vulnerability did not differ between the participant groups, although more severely depressed participants tended to be less respectful of health guidelines. In addition, the most heightened effects on the depressed participants were boredom and the feeling of social isolation, which was not compensated by the search for social affiliation. Supporting people with depression should be a public health priority because they suffer psychologically more than others from the pandemic and the lockdown.

The present study evaluates the updating of long-term memory for duration. After learning a temporal discrimination associating one lever with a standard duration (4 sec) and another lever with both a shorter (1-sec) and a longer (16-sec) duration, rats underwent a single session for learning a new standard duration. The temporal generalization gradient obtained 24 h later showed a modification in long-term memory for durations longer than the standard but only when the new duration was longer than the one initially learned. The effect was confirmed for another set of durations (0.5-2-8 sec). Our study demonstrates asymmetry in updating long-term memory for time., (© 2021 Derouet et al.; Published by Cold Spring Harbor Laboratory Press.)

To fight against the spread of the coronavirus disease, more than 3 billion people in the world have been confined indoors. Although lockdown is an efficient solution, it has had various psychological consequences that have not yet been fully measured. During the lockdown period in France (April 2020), we conducted two surveys on two large panels of participants to examine how the lockdown disrupted their relationship with time and what this change in their experiences of time means. Numerous questions were asked about the experience of time but also the nature of life during the lockdown: the emotions felt, boredom, the activities performed, sleep quality, and the daily rhythm. The participants also completed a series of self-reported scales used to assess depression, anxiety, and impulsivity. The results showed that time seemed to pass more slowly during the lockdown compared to before. This feeling of a slowing down of time has little to do with living conditions during the lockdown and individual psychological characteristics. The main predictor of this time experience was boredom and partly mediated by the lack of activity. The feeling of being less happy and the presence of sleep disturbance also explained this specific experience of time albeit to a lesser extent., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Martinelli, Gil, Belletier, Chevalère, Dezecache, Huguet and Droit-Volet.)

This study examined the effect of emotion on the judgment of durations of several minutes compared with that of durations of a few seconds. Three experiments were performed on the temporal judgment of emotional stimuli lasting from 2 s to 6 min (Experiment 1) or from 2 to 6 min (Experiment 2 and 3). These involved emotional sounds (Experiment 1 and 2) or virtual reality emotional films (Experiment 3). The results showed an increase in the lengthening of the perceived duration as the level of arousal and negative valence of the emotional stimuli increased, both for the long durations of several minutes and for the shorter durations. However, the magnitude of the time distortion tended to decrease as the length of the duration increased because the affects experienced by the participants lost their intensity over time. Nonetheless, when the exposure to emotional stimuli was limited and the stimuli were sufficiently arousing, as in Experiments 2 and 3, people overestimated time across durations ranging from seconds to minutes., (Copyright © 2020 Elsevier B.V. All rights reserved.)

A lockdown of people has been used as an efficient public health measure to fight against the exponential spread of the coronavirus disease (Covid-19) and allows the health system to manage the number of patients. The aim of this study (clinicaltrials.gov NCT00430818) was to evaluate the impact of both perceived stress aroused by Covid-19 and of emotions triggered by the lockdown situation on the individual experience of time. A large sample of the French population responded to a survey on their experience of the passage of time during the lockdown compared to before the lockdown. The perceived stress resulting from Covid-19 and stress at work and home were also assessed, as were the emotions felt. The results showed that people have experienced a slowing down of time during the lockdown. This time experience was not explained by the levels of perceived stress or anxiety, although these were considerable, but rather by the increase in boredom and sadness felt in the lockdown situation. The increased anger and fear of death only explained a small part of variance in the time judgment. The conscious experience of time therefore reflected the psychological difficulties experienced during lockdown and was not related to their perceived level of stress or anxiety., Competing Interests: No authors have competing interests.

Using an out-of-body paradigm, the present study provided further empirical evidence for the theory of embodied time by suggesting that the body-self plays a key role in time judgments. Looking through virtual reality glasses, the participants saw the arm of a mannequin instead of their own arm. They had to judge the duration of the interval between two (perceived) touches applied to the mannequin's body after a series of strokes had been viewed being made to the mannequin and tactile strokes had been administered to the participants themselves. These strokes were administered either synchronously or asynchronously. During the interval, a pleasant (touch with a soft paintbrush) or an unpleasant stimulation (touch with a pointed knife) was applied to the mannequin. The results showed that the participants felt the perceived tactile stimulations in their own bodies more strongly after the synchronous than the asynchronous stroking condition, a finding which is consistent with the out-of-body illusion. In addition, the interval duration was judged longer in the synchronous than in the asynchronous condition. This time distortion increased the greater the individual out-of-body experience was. Our results therefore highlight the importance of the awareness of the body-self in the processing of time, i.e., the significance of embodied time., Competing Interests: The authors declare there are no competing interests., (©2020 Droit-Volet et al.)

We examined the role of action in motor and perceptual timing across development. Adults and children aged 5 or 8 years old learned the duration of a rhythmic interval with or without concurrent action. We compared the effects of sensorimotor versus visual learning on subsequent timing behaviour in three different tasks: rhythm reproduction (Experiment 1), rhythm discrimination (Experiment 2) and interval discrimination (Experiment 3). Sensorimotor learning consisted of sensorimotor synchronization (tapping) to an isochronous visual rhythmic stimulus (ISI = 800 ms), whereas visual learning consisted of simply observing this rhythmic stimulus. Results confirmed our hypothesis that synchronized action during learning systematically benefitted subsequent timing performance, particularly for younger children. Action-related improvements in accuracy were observed for both motor and perceptual timing in 5 years olds and for perceptual timing in the two older age groups. Benefits on perceptual timing tasks indicate that action shapes the cognitive representation of interval duration. Moreover, correlations with neuropsychological scores indicated that while timing performance in the visual learning condition depended on motor and memory capacity, sensorimotor learning facilitated an accurate representation of time independently of individual differences in motor and memory skill. Overall, our findings support the idea that action helps children to construct an independent and flexible representation of time, which leads to coupled sensorimotor coding for action and time., (© 2019 John Wiley & Sons Ltd.)