Mice monitor their timing errors.

Animals often engage in representationally guided goal-directed behaviors. These behaviors are thus also subjected to representational uncertainty (e.g. timing uncertainty during waiting), which has been previously shown to adaptively guide behaviors normatively. These observations raise the question of whether non-human animals can track the direction and magnitude of their timing errors (i.e. temporal error monitoring). Only a few studies have investigated this question without addressing the key components of temporal error monitoring (e.g. due to differential reinforcement of metacognitive judgments and primary task representation). We conducted the critical test of temporal error monitoring in mice by developing a novel behavioral task that involved temporal production that exponentially favored temporal accuracy and minimized the contribution of sensorimotor noise. The response rate for an upcoming probabilistic reward following the timing performance was used as a proxy for confidence. We found that mice exhibited high reward expectancy after accurate and low reward expectancy after inaccurate timing performance. The reward expectancy decreased as a function of deviations from the target interval for the short and long reproductions; pointing to the symmetrical sensitivity of metacognition to shorter/longer than target responses. These findings suggest a complete temporal error monitoring ability for mice with human-like metacognitive features.

Mechanically Induced Motor Tremors Disrupt the Perception of Time.

Contemporary research has begun to show a strong relationship between movements and the perception of time. More specifically, concurrent movements serve to both bias and enhance time estimates. To explain these effects, we recently proposed a mechanism by which movements provide a secondary channel for estimating duration that is combined optimally with sensory estimates. However, a critical test of this framework is that by introducing "noise" into movements, sensory estimates of time should similarly become noisier. To accomplish this, we had human participants move a robotic arm while estimating intervals of time in either auditory or visual modalities (n = 24, ea.). Crucially, we introduced an artificial "tremor" in the arm while subjects were moving, that varied across three levels of amplitude (1-3 N) or frequency (4-12 Hz). The results of both experiments revealed that increasing the frequency of the tremor led to noisier estimates of duration. Further, the effect of noise varied with the base precision of the interval, such that a naturally less precise timing (i.e., visual) was more influenced by the tremor than a naturally more precise modality (i.e., auditory). To explain these findings, we fit the data with a recently developed drift-diffusion model of perceptual decision-making, in which the momentary, within-trial variance was allowed to vary across conditions. Here, we found that the model could recapitulate the observed findings, further supporting the theory that movements influence perception directly. Overall, our findings support the proposed framework, and demonstrate the utility of inducing motor noise via artificial tremors.

Native language background affects the perception of duration and pitch.

Estonian is a quantity language with both a primary duration cue and a secondary pitch cue, whereas Chinese is a tonal language with a dominant pitch use. Using a mismatch negativity experiment and a behavioral discrimination experiment, we investigated how native language background affects the perception of duration only, pitch only, and duration plus pitch information. Chinese participants perceived duration in Estonian as meaningless acoustic information due to a lack of phonological use of duration in their native language; however, they demonstrated a better pitch discrimination ability than Estonian participants. On the other hand, Estonian participants outperformed Chinese participants in perceiving the non-speech pure tones that resembled the Estonian quantity (i.e., containing both duration and pitch information). Our results indicate that native language background affects the perception of duration and pitch and that such an effect is not specific to processing speech sounds.

Ramping cells in the rodent medial prefrontal cortex encode time to past and future events via real Laplace transform.

In interval reproduction tasks, animals must remember the event starting the interval and anticipate the time of the planned response to terminate the interval. The interval reproduction task thus allows for studying both memory for the past and anticipation of the future. We analyzed previously published recordings from the rodent medial prefrontal cortex [J. Henke et al., eLife10, e71612 (2021)] during an interval reproduction task and identified two cell groups by modeling their temporal receptive fields using hierarchical Bayesian models. The firing in the "past cells" group peaked at the start of the interval and relaxed exponentially back to baseline. The firing in the "future cells" group increased exponentially and peaked right before the planned action at the end of the interval. Contrary to the previous assumption that timing information in the brain has one or two time scales for a given interval, we found strong evidence for a continuous distribution of the exponential rate constants for both past and future cell populations. The real Laplace transformation of time predicts exponential firing with a continuous distribution of rate constants across the population. Therefore, the firing pattern of the past cells can be identified with the Laplace transform of time since the past event while the firing pattern of the future cells can be identified with the Laplace transform of time until the planned future event.

Mental time travel in animals: the 'when' of mental time travel.

While many aspects of cognition have been shown to be shared between humans and non-human animals, there remains controversy regarding whether the capacity to mentally time travel is a uniquely human one. In this paper, we argue that there are four ways of representing when some event happened: four kinds of temporal representation. Distinguishing these four kinds of temporal representation has five benefits. First, it puts us in a position to determine the particular benefits these distinct temporal representations afford an organism. Second, it provides the conceptual resources to foster a discussion about which of these representations is necessary for an organism to count as having the capacity to mentally time travel. Third, it enables us to distinguish stricter from more liberal views of mental time travel that differ regarding which kind(s) of temporal representation is taken to be necessary for mental time travel. Fourth, it allows us to determine the benefits of taking a stricter or more liberal view of mental time travel. Finally, it ensures that disagreement about whether some species can mentally time travel is not merely the product of unrecognized disagreement about which temporal representation is necessary for mental time travel. We argue for a more liberal view, on the grounds that it allows us to view mental time travel as an evolutionarily continuous phenomenon and to recognize that differences in the ways that organisms mentally time travel might reflect different temporal representations, or combinations thereof, that they employ. Our ultimate aim, however, is to create a conceptual framework for further discussion regarding what sorts of temporal representations are required for mental time travel.This article is part of the theme issue 'Elements of episodic memory: lessons from 40 years of research'.

The recursive grammar of mental time travel.

One apparent feature of mental time travel is the ability to recursively embed temporal perspectives across different times: humans can remember how we anticipated the future and anticipate how we will remember the past. This recursive structure of mental time travel might be formalized in terms of a 'grammar' that is reflective of but more general than linguistic notions of absolute and relative tense. Here, I provide a foundation for this grammatical framework, emphasizing a bounded (rather than unbounded) recursive function that supports mental time travel to a limited temporal depth and to actual and possible scenarios. Anticipated counterfactual thinking, for instance, entails three levels of mental time travel to a possible scenario ('in the future, I will reflect on how my past self could have taken a different future action') and is centrally implicated in complex human decision-making. This perspective calls for further research into the mechanisms, ontogeny, functions and phylogeny of recursive mental time travel, and revives the question of links with other recursive forms of thinking such as theory of mind. This article is part of the theme issue 'Elements of episodic memory: lessons from 40 years of research'.

Insights into the interaction between time and reward prediction on the activity of striatal tonically active neurons: A pilot study in rhesus monkeys.

Prior studies have documented the role of the striatum and its dopaminergic input in time processing, but the contribution of local striatal cholinergic innervation has not been specifically investigated. To address this issue, we recorded the activity of tonically active neurons (TANs), thought to be cholinergic interneurons in the striatum, in two male macaques performing self-initiated movements after specified intervals in the seconds range have elapsed. The behavioral data showed that movement timing was adjusted according to the temporal requirements. About one-third of all recorded TANs displayed brief depressions in firing in response to the cue that indicates the interval duration, and the strength of these modulations was, in some instances, related to the timing of movement. The rewarding outcome of actions also impacted TAN activity, as reflected by stronger responses to the cue paralleled by weaker responses to reward when monkeys performed correctly timed movements over consecutive trials. It therefore appears that TAN responses may act as a start signal for keeping track of time and reward prediction could be incorporated in this signaling function. We conclude that the role of the striatal cholinergic TAN system in time processing is embedded in predicting rewarding outcomes during timing behavior.

Age-related changes in time perception: Effects of immersive virtual reality and spatial location of stimuli.

The perception of time is subject to various environmental influences and exhibits changes across the lifespan. Studies on time perception have often been conducted using abstract stimuli and artificial scenarios, and recent claims for more naturalistic paradigms and realistic stimuli pose the question as to whether immersive virtual reality set-ups differently affect the timing abilities of older versus younger adults. Here, we tested the hypotheses that naturalistic 3D stimuli presented in immersive virtual reality (as opposed to abstract 2D stimuli presented on a computer screen) and the spatial location of those stimuli (left vs. right) affect the perceived time point of their occurrence. Our results demonstrate that a naturalistic presentation of stimuli leads to a bias towards earlier time points in younger, but not older participants. Furthermore, this bias was associated with lower scores of memory capacity. Contrary to our hypothesis that right-sided stimuli are perceived as later than left-sided stimuli, no spatial influences on temporal processing were observed. These results show that older and younger adults are differently affected by an increase in the realism and the immersiveness of experimental paradigms, and highlight the importance of task design in studies on human time perception.

Self and time in individuals with schizophrenia: A motor component?

Phenomenology suggests a disruption in the experience of time in individuals with schizophrenia, related to disorders of the sense of self. Patients themselves relate a fragmentation of their temporal experience and of their sense of self. Temporal expectations help relate the present moment to the future and we have previously shown that temporal expectations are fragile in patients, and relate to disorders of the self. Here, we investigate whether patients' performance is still impaired when the motor response to the expected event can be prepared in advance. In two different experiments participants (41 patients vs. 43 neurotypicals in total) responded to a visual target occurring at a variable interval (or "foreperiod") after an initial warning signal. Moreover, in Experiment 1 we measured the sense of self with the EASE scale. We observed the usual benefit of the passage of time: the longer the waiting period, the better the preparation, and the faster the responses. However, this effect also comprises sequential (surprise) effects, when a target occurs earlier than on the preceding trial. We evaluated the effect of the passage of time, by isolating trials that followed a trial with the same foreperiod. The benefit of long, versus short, foreperiods was still observed in controls but disappeared in patients. The results suggest that the benefit of the passage of time is diminished in patients and relates to self disorders, even when the task allows for motor preparation. The results suggest that a non-verbal impairment sub-tends disorders of the sense of self.

Time perspective and attachment predict perceived stress in Lebanese undergraduates: The mediating role of trait emotional intelligence.

BACKGROUND: Lebanese university students experience high levels of stress, which are linked to poor academic and health outcomes. Therefore, understanding the psychological predictors of this stress is crucial. The present study examines the roles of emotional, cognitive, and interpersonal factors in predicting perceived stress, namely trait emotional intelligence (trait EI), time perspective, and attachment. METHODS: The sample included 283 Lebanese undergraduate university students aged 18 to 33 years (M = 19.89, SD = 1.87). The main variables were assessed using the Trait Emotional Intelligence Questionnaire - Short Form, The Zimbardo Time Perspective Inventory, The Revised Adult Attachment Scale - Close Relationships Version, and the Perceived Stress Scale. RESULTS: Path analysis showed that trait EI mediated the relationship between time perspective and attachment (predictors) and perceived stress (outcome). In particular, the Past Positive and Future time perspectives positively predicted trait EI, while insecure attachment negatively predicted it. In turn, higher trait EI predicted lower perceived stress. CONCLUSION: The findings help inform theory and application, suggesting that managing stress and mitigating its impact on well-being can be achieved through interventions targeting time perspective, attachment, and trait EI.

Mechanism of Duration Perception in Artificial Brains Suggests New Model of Attentional Entrainment.

While cognitive theory has advanced several candidate frameworks to explain attentional entrainment, the neural basis for the temporal allocation of attention is unknown. Here we present a new model of attentional entrainment guided by empirical evidence obtained using a cohort of 50 artificial brains. These brains were evolved in silico to perform a duration judgment task similar to one where human subjects perform duration judgments in auditory oddball paradigms. We found that the artificial brains display psychometric characteristics remarkably similar to those of human listeners and exhibit similar patterns of distortions of perception when presented with out-of-rhythm oddballs. A detailed analysis of mechanisms behind the duration distortion suggests that attention peaks at the end of the tone, which is inconsistent with previous attentional entrainment models. Instead, the new model of entrainment emphasizes increased attention to those aspects of the stimulus that the brain expects to be highly informative.

The sands of time: Discontinuity in time production, or inadequacy of psychophysical fit?

In a recent study employing time production, a number of participants presented aberrant data, which normally would have marked them as being outliers. Given the ongoing discussion in the literature regarding the illusory nature of the flow of time, in this paper we consider whether their data may indicate discontinuity in time perception. We analyze the log-log plots for these outliers, investigating to what degree linearity is preserved for all the data points, as opposed to achieving a better fit using bisegmental regression. The current results, though preliminary, can contribute to the debate regarding the non-linearity of subjective time. It would seem that with longer target durations, the ongoing experience of time can be either one of a subjective slowing down of time (longer time units, increase in slope), or of a subjective speeding up of time (shorter time units, decrease in slope).

Is life going too fast? Exploring the unique and joint contributions of mindfulness, temperament, task load, and metacognitions about time.

BACKGROUND: Previous research has shown that mindfulness is associated with slower passage of time in everyday life, and with lower self-reported time pressure. This study investigates some of the potential mechanisms behind these relationships. METHODS: 318 participants submitted their responses to an online survey which collected data regarding passage of time judgments, time pressure, trait mindfulness, temperament, task load, and metacognitions about time. Using commonality and dominance analyses, we explored how these variables contributed, either alone or jointly, to predicting how fast (or slow) time seems to pass for participants, or how pressed for time they felt. RESULTS: Mindfulness and temperament had some overlaps in their ability to predict passage of time judgments and time pressure for durations at the month and 2-month scales. The temperamental trait of extraversion/surgency, as well as the Non-judging and Non-reacting facets of mindfulness were among the best predictors of passage of time judgments and time pressure. Attention-related variables were mainly related to time perception via their involvement in joint effects with other variables. Results also suggested that metacognitions about time interacted with other variables in predicting passage of time judgments, but only at the month scale. Finally, among all the variables included in this study, task load had the highest degree of involvement in predictions of self-reported time pressure at the week and month scales, but it contributed relatively little to predicting passage of time judgments. CONCLUSIONS: Results suggest that mindfulness relates to passage of time through its involvement in inferential processes. The data also shows how different factors are related to PoTJ at different time scales. Finally, results suggest the existence of both similarities and differences in how passage of time and time pressure relate to the other included variables.

Time consciousness: Silence, mindfulness, and subjective time perception.

Although recent theories of consciousness have emerged to define what consciousness is, an under-represented aspect within this field remains: time consciousness. However, the subjective passage of time is modulated by changing experiences within different situational contexts and by self-awareness. The experience of silence influences our awareness of self, space, and time, and it impacts on psychological well-being. The present review describes how self and time are influenced by different situations of silence (pure silence indoors and outdoors, the "just thinking" situation, and the combination of silence with deep relaxation). Also, the changes in time experience during a "forced" waiting situation due to the COVID-19 lockdown are presented in order to highlight the role of boredom in waiting situations and in situations in which we are alone with "our thoughts." Finally, in the context of the importance of creating silence through meditation practices, the alterations to one's sense of self and time during mindfulness meditation are reviewed. These studies are discussed within the framework of the cognitive models of prospective time perception, such as the attentional-gate model and the model of self-regulation and self-awareness.

Temporal context modulates cross-modality time discrimination: Electrophysiological evidence for supramodal temporal representation.

Although the peripheral nervous system lacks a dedicated receptor, the brain processes temporal information through different sensory channels. A critical question is whether temporal information from different sensory modalities at different times forms modality-specific representations or is integrated into a common representation in a supramodal manner. Behavioral studies on temporal memory mixing and the central tendency effect have provided evidence for supramodal temporal representations. We aimed to provide electrophysiological evidence for this proposal by employing a cross-modality time discrimination task combined with electroencephalogram (EEG) recordings. The task maintained a fixed auditory standard duration, whereas the visual comparison duration was randomly selected from the short and long ranges, creating two different audio-visual temporal contexts. The behavioral results showed that the point of subjective equality (PSE) in the short context was significantly lower than that in the long context. The EEG results revealed that the amplitude of the contingent negative variation (CNV) in the short context was significantly higher (more negative) than in the long context in the early stage, while it was lower (more positive) in the later stage. These results suggest that the audiovisual temporal context is integrated with the auditory standard duration to generate a subjective time criterion. Compared with the long context, the subjective time criterion in the short context was shorter, resulting in earlier decision-making and a preceding decrease in CNV. Our study provides electrophysiological evidence that temporal information from different modalities inputted into the brain at different times can form a supramodal temporal representation.

Exploring the interplay between addiction and time perception: A systematic review and meta-analysis.

Prior studies have investigated the immediate impacts of substances on temporal perception, the impact of temporal outlook, and the consequences of modified temporal perception on addictive behaviors. These inquiries have provided valuable perspectives on the intricate associations between addiction and time perception, enriching the groundwork for forthcoming research and therapeutic strategies. This comprehensive review aims to further explore intricate correlation among diverse addictive substances-namely alcohol, cannabis, nicotine, opioids-and non-substance addictions such as internet gaming, elucidating their influence on temporal perception. Adhering to the PICOS method and adhering to PRISMA guidelines, we systematically reviewed and critically evaluated all existing research concerning temporal perception in individuals with substance and non-substance use disorders. Specifically, our analyses involved 31 pertinent articles encompassing six unique groups-alcohol, nicotine, cannabis, stimulants, opioids, and internet-related addictions-sourced from a pool of 551 papers. The findings revealed differences in time perception between addicts and control groups, as indicated by medium to large effect sizes (Hedge's g = 0.8, p < 0.001). However, the nature of these differences-whether they predominantly involve time overestimation or underestimation-is not yet definitively clear. This variability underscores the complexity of the relationship between addiction and temporal perception, paving the way for further research to unravel these intricate dynamics.

The impact of temporal processing on reading in dyslexia with rapid automatized naming deficits.

In the present study, we aimed to investigate the different impacts of temporal processing on reading by Chinese children with and without dyslexia. In total, 27 children with dyslexia who had a deficit in rapid automatized naming (RAN) (D_R), 37 children with dyslexia who had deficits in both RAN and phonological awareness (PA) (D_RP), and 40 typically developing children (TD) were recruited in Taiwan. The children were asked to complete non-verbal intelligence, PA, RAN, Chinese character reading tasks and an auditory temporal order judgement (ATOJ) task. Our results of a multiple regression model showed that the ATOJ accounted for unique variances in the reading differences between the children in the D_R and TD groups; performance was controlled for non-verbal intelligence, PA and RAN tasks. Theoretically, we provide possible explanations for the controversial findings in the field of Chinese children with dyslexia and, practically, suggest different interventions should be provided for children with dyslexia with different underlying impairments.

Musical Expertise Influences the Processing of Short and Long Auditory Time Intervals: An Electroencephalography Study.

Musical expertise has been proven to be beneficial for time perception abilities, with musicians outperforming nonmusicians in several explicit timing tasks. However, it is unclear how musical expertise impacts implicit time perception. Twenty nonmusicians and 15 expert musicians participated in an EEG recording during a passive auditory oddball paradigm with 0.8- and 1.6-sec standard time intervals and deviant intervals that were either played earlier or delayed relative to the standard interval. We first confirmed that, as was the case for nonmusicians, musicians use different neurofunctional processes to support the perception of short (below 1.2 sec) and long (above 1.2 sec) time intervals: Whereas deviance detection for long intervals elicited a N1 component, P2 was associated with deviance detection for short time intervals. Interestingly, musicians did not elicit a contingent negative variation (CNV) for longer intervals but show additional components of deviance detection such as (i) an attention-related N1 component, even for deviants occurring during short intervals; (ii) a N2 component for above and below 1.2-sec deviance detection, and (iii) a P2 component for above 1.2-sec deviance detection. We propose that the N2 component is a marker of explicit deviance detection and acts as an inhibitory/conflict monitoring of the deviance. This hypothesis was supported by a positive correlation between CNV and N2 amplitudes: The CNV reflects the temporal accumulator and can predict explicit detection of the deviance. In expert musicians, a N2 component is observable without CNV, suggesting that deviance detection is optimized and does not require the temporal accumulator. Overall, this study suggests that musical expertise is associated with optimized implicit time perception.

Anticipation of sexually arousing visual event leads to overestimation of elapsed time.

Subjective estimates of duration are affected by emotional expectations about the future. For example, temporal intervals preceding a threatening event such as an electric shock are estimated as longer than intervals preceding a non-threatening event. However, it has not been unequivocally shown that such temporal overestimation occurs also when anticipating a similarly arousing but appealing event. In this study, we examined how anticipation of visual erotic material influenced perceived duration. Participants did a temporal bisection task, where they estimated durations of visual cues relative to previously learned short and long standard durations. The color of the to-be-timed visual cue signalled either a chance of seeing a preferred erotic picture at the end of the interval or certainty of seeing a neutral grey bar instead. The results showed that anticipating an appealing event increased the likelihood of estimating the cue duration as long as compared to the anticipation of a grey bar. Further analyses showed that this temporal overestimation effect was stronger for those who rated the anticipated erotic pictures as more sexually arousing. The results thus indicate that anticipation of appealing events has a similar dilating effect on perceived duration as does the anticipation of aversive events.