Temporal context effects are associated with cognitive status in advanced age

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.

Rapid calibration to dynamic temporal contexts

The prediction of future events and the preparation of appropriate behavioural reactions rely on an accurate perception of temporal regularities. In dynamic environments, temporal regularities are subject to slow and sudden changes, and adaptation to these changes is an important requirement for efficient behaviour. Bayesian models have proven a useful tool to understand the processing of temporal regularities in humans; yet an open question pertains to the degree of flexibility of the prior that is required for optimal modelling of behaviour. Here we directly compare dynamic models (with continuously changing prior expectations) and static models (a stable prior for each experimental session) with their ability to describe regression effects in interval timing. Our results show that dynamic Bayesian models are superior when describing the responses to slow, continuous environmental changes, whereas static models are more suitable to describe responses to sudden changes. In time perception research, these results will be informative for the choice of adequate computational models and enhance our understanding of the neuronal computations underlying human timing behaviour.

Validating virtual reality for time perception research: Virtual reality changes expectations about the duration of physical processes, but not the sense of time

Immersive virtual reality (VR) provides a versatile method for investigating human time perception, because it allows the manipulation and control of relevant variables (e.g., the speed of environmental changes) that cannot be modified in the real world. However, an important premise for interpreting the results of VR studies, namely that the method itself does not affect time perception, has received little attention. Here we tested this assumption by comparing timing performance in a real environment and a VR scenario. Participants performed two timing tasks, requiring the production of intervals defined either by numerical values ("eight seconds") or by a physical process ("the time it takes for a bottle to run out when turned over"). We found that the experience of immersive VR exclusively altered judgments about the duration of physical processes, whereas judgments about the duration of abstract time units were unaffected. These results demonstrate that effects of VR on timing performance are not driven by changes in time perception itself, but rather by altered expectations regarding the duration of physical processes. The present study validates the use of VR in time perception research and strengthens the interpretation of changed timing behaviour induced by manipulations within VR.

Differences between sub-second and supra-second durations for the assessment of timing deficits in amnestic mild cognitive impairment

Previous studies have often reported timing deficits in older adults with different degrees of cognitive decline, however, the exact nature of impairments in time perception is still to be elucidated. In particular, it is unclear if the deficits are more pronounced for short or long intervals, consistent with notions that different cognitive processes and neuroanatomical areas are involved in the processing of durations of different ranges. The present study aims to further investigate timing abilities in amnestic mild cognitive impairment (aMCI) patients and age-matched controls. Participants were asked to decide whether an acoustic event occurred within the first or the second half of a reference duration. The results revealed a bias towards larger PSE values and reduced precision in aMCI patients compared to healthy controls. Further analyses showed that the bias towards larger PSE values correlated with memory performance, especially when sub-second durations were tested. Overall, the results demonstrate that memory deficits in aMCI patients coincide with changes in time perception in the sub-second interval range.

Effect of tempo on the age-related changes in temporal expectation driven by rhythms

Temporal expectation refers to the capacity to allocate resources at a particular point in time, enabling us to enhance our behavior performance. Empirical evidence indicates that, among younger adults, temporal expectation can be driven by rhythm (i.e., regular sequences of stimuli). However, whether there are age-related changes in rhythm-based temporal expectation has not been clearly established. Furthermore, whether tempo can influence the relationship between rhythm-based temporal expectation and aging remains unexplored. To address these questions, both younger and older participants took part in a rhythm-based temporal expectation task, engaging three distinct tempos: 600 ms (fast), 1800 ms (moderate), or 3000 ms (slow). The results demonstrated that temporal expectation effects (i.e., participants exhibited significantly faster responses during the regular trials compared to the irregular trials) were observed in both the younger and older participants under the moderate tempo condition. However, in the fast and slow tempo conditions, the temporal expectation effects were solely observed in the younger participants. These findings revealed that rhythm-based temporal expectations can be preserved during aging but within a specific tempo range. When the tempo falls within the range of either being too fast or too slow, it can manifest age-related declines in temporal expectations driven by rhythms.

The effect of aging and emotions on time processing

BACKGROUND

Time perception is an automatic process that can be influenced by intrinsic and extrinsic factors.

AIMS

This study aimed to investigate the effect of age and emotions on the ability to keep track of short suprasecond intervals.

METHODS

Younger adults (N = 108, age range: 18-35) and older adults (N = 51, age range: 65-87) were asked to reproduce, bisect, or double the duration of facial stimuli randomly presented for 1500, 3000, and 4500 ms. The experiment included facial stimuli with positive, negative, or neutral expressions.

RESULTS

The participants across age correctly reproduced intervals but overestimated and underestimated them when asked to bisect and double the intervals, respectively. Overall, when faces were presented with a positive or negative expression, an overestimation of time intervals emerged compared to faces with neutral expressions. Emotions had a greater effect on older adults, who showed a greater overestimation of positive facial expressions and an underestimation of sad, but not angry, facial expressions.

DISCUSSION

The results provide evidence that time perception is influenced by age and emotions, with older adults showing a greater effect of emotions on time processing.

CONCLUSION

The study suggests an interaction among time processing, age, and emotions, highlighting an automatic relationship among these domains, often considered independent.

Reducing the tendency for chronometric counting in duration discrimination tasks

Chronometric counting is a prevalent issue in the study of human time perception as it reduces the construct validity of tasks and can conceal existing timing deficits. Several methods have been proposed to prevent counting strategies, but the factors promoting those strategies in specific tasks are largely uninvestigated. Here, we modified a classical two-interval duration discrimination task in two aspects that could affect the tendency to apply counting strategies. We removed the pause between the two intervals and changed the task instructions: Participants decided whether a short event occurred in the first or in the second half of a reference duration. In Experiment 1, both classical and modified task versions were performed under timing conditions, in which participants were asked not to count, and counting conditions, in which counting was explicitly instructed. The task modifications led to (i) a general decrease in judgment precision, (ii) a shift of the point of subjective equality, and (iii) a counting-related increase in reaction times, suggesting enhanced cognitive effort of counting during the modified task version. Precision in the two task versions was not differently affected by instructed counting. Experiment 2 demonstrates that—in the absence of any counting-related instructions—participants are less likely to engage in spontaneous counting in the modified task version. These results enhance our understanding of the two-interval duration discrimination task and demonstrate that the modifications tested here—although they do not significantly reduce the effectiveness of instructed counting—can diminish the spontaneous tendency to adopt counting strategies.

Explicit and implicit timing in older adults: Dissociable associations with age and cognitive decline

This study aimed to test two common explanations for the general finding of age-related changes in the performance of timing tasks within the millisecond-to-second range intervals. The first explanation is that older adults have a real difficulty in temporal processing as compared to younger adults. The second explanation is that older adults perform poorly on timing tasks because of their reduced cognitive control functions. These explanations have been mostly contrasted in explicit timing tasks that overtly require participants to process interval durations. Fewer studies have instead focused on implicit timing tasks, where no explicit instructions to process time are provided. Moreover, the investigation of both explicit and implicit timing in older adults has been restricted so far to healthy older participants. Here, a large sample (N = 85) comprising not only healthy but also pathological older adults completed explicit (time bisection) and implicit (foreperiod) timing tasks within a single session. Participants’ age and cognitive decline, measured with the Mini-Mental State Examination (MMSE), were used as continuous variables to explain performance on explicit and implicit timing tasks. Results for the explicit timing task showed a flatter psychometric curve with increasing age or decreasing MMSE scores, pointing to a deficit at the level of cognitive control functions rather than of temporal processing. By contrast, for the implicit timing task, a decrease in the MMSE scores was associated with a reduced foreperiod effect, an index of implicit time processing. Overall, these findings extend previous studies on explicit and implicit timing in healthy aged samples by dissociating between age and cognitive decline (in the normal-to-pathological continuum) in older adults.

Benefits of Adaptive Learning Transfer From Typing-Based Learning to Speech-Based Learning

Memorising vocabulary is an important aspect of formal foreign-language learning. Advances in cognitive psychology have led to the development of adaptive learning systems that make vocabulary learning more efficient. One way these computer-based systems optimize learning is by measuring learning performance in real time to create optimal repetition schedules for individual learners. While such adaptive learning systems have been successfully applied to word learning using keyboard-based input, they have thus far seen little application in word learning where spoken instead of typed input is used. Here we present a framework for speech-based word learning using an adaptive model that was developed for and tested with typing-based word learning. We show that typing- and speech-based learning result in similar behavioral patterns that can be used to reliably estimate individual memory processes. We extend earlier findings demonstrating that a response-time based adaptive learning approach outperforms an accuracy-based, Leitner flashcard approach in learning efficiency (demonstrated by higher average accuracy and lower response times after a learning session). In short, we show that adaptive learning benefits transfer from typing-based learning, to speech based learning. Our work provides a basis for the development of language learning applications that use real-time pronunciation assessment software to score the accuracy of the learner’s pronunciations. We discuss the implications for our approach for the development of educationally relevant, adaptive speech-based learning applications.

Age-related changes in time perception: The impact of naturalistic environments and retrospective judgements on timing performance

Reduced timing abilities have been reported in older adults and are associated with pathological cognitive decline. However, time perception experiments often lack ecological validity. Especially the reduced complexity of experimental stimuli and the participants' awareness of the time-related nature of the task can influence lab-assessed timing performance and thereby conceal age-related differences. An approximation of more naturalistic paradigms can provide important information about age-related changes in timing abilities. To determine the impact of higher ecological validity on timing experiments, we implemented a paradigm that allowed us to test (1) the effect of embedding the to-be-timed stimuli within a naturalistic visual scene and (2) the effect of retrospective time judgements, which are more common in real life than prospective judgements. The results show that compared with out-of-context stimuli, younger adults benefit from a naturalistic embedding of stimuli (reflected in higher precision and less errors), whereas the performance of older adults is reduced when confronted with naturalistic stimuli. Differences between retrospective and prospective time judgements were not modulated by age. We conclude that, potentially driven by difficulties in suppressing temporally irrelevant environmental information, the contextual embedding of naturalistic stimuli can affect the degree to which age influences the performance in time perception tasks.