The Effects of Subthreshold Autistic Traits On Time Perception: The Regulation of Interpersonal Information Association

Background People with high subthreshold autistic traits usually show structural impairments like those with autism spectrum disorder, but with less social and cognitive impairments. The effect of autistic traits on time perception and the role of interpersonal information on this effect remains unexplored. Methods This study used a temporal bisection task between 400–1600 ms to compare the time perception of individuals with higher and lower autistic traits, and to explore the influence of interpersonal information on their time perception by establishing associations between interpersonal information and geometric figures. A total of 32 participants with high autistic traits and 31 participants with low autistic traits took part in the study. Results In the absence of identity information, people with high autistic traits tended to judge short durations as longer, and their Weber ratio was higher than those with low autistic traits, suggesting that their overestimation of short duration is due to decreased temporal sensitivity and increased internal clock frequency. With the addition of interpersonal information, individuals with high and low autistic traits had faster responses to self in the identity-figure association, and the subjective bisection point was shorter. However, it took longer for individuals with high autistic traits to build the self-association, and there was no difference in the proportion of long response and Weber ratio between individuals with high and low autistic traits when identity was involved. Conclusion These results suggest that individuals with high autistic traits have a higher central tendency, and this change is related to the decline of perceptual sensitivity. Actively guiding attention to interpersonal information can improve the time perception sensitivity of individuals with high autistic traits.

Numerical Magnitude Affects Accuracy but Not Precision of Temporal Judgments

A Theory of Magnitude (ATOM) suggests that space, time, and quantities are processed through a generalized magnitude system. ATOM posits that task-irrelevant magnitudes interfere with the processing of task-relevant magnitudes as all the magnitudes are processed by a common system. Many behavioral and neuroimaging studies have found support in favor of a common magnitude processing system. However, it is largely unknown whether such cross-domain monotonic mapping arises from a change in the accuracy of the magnitude judgments or results from changes in precision of the processing of magnitude. Therefore, in the present study, we examined whether large numerical magnitude affects temporal accuracy or temporal precision, or both. In other words, whether numerical magnitudes change our temporal experience or simply bias duration judgments. The temporal discrimination (between comparison and standard duration) paradigm was used to present numerical magnitudes (“1,” “5,” and “9”) across varied durations. We estimated temporal accuracy (PSE) and precision (Weber ratio) for each numerical magnitude. The results revealed that temporal accuracy (PSE) for large (9) numerical magnitude was significantly lower than that of small (1) and identical (5) magnitudes. This implies that the temporal duration was overestimated for large (9) numerical magnitude compared to small (1) and identical (5) numerical magnitude, in line with ATOM’s prediction. However, no influence of numerical magnitude was observed on temporal precision (Weber ratio). The findings of the present study suggest that task-irrelevant numerical magnitude selectively affects the accuracy of processing of duration but not duration discrimination itself. Further, we argue that numerical magnitude may not directly affect temporal processing but could influence via attentional mechanisms.

Identification of an Age Maturity in Time Discrimination Abilities

The aim of this study was to identify the age at which parameters of timing performance in a temporal bisection task converge on an adult-like stable level. Participants in the three- to 20-year-old range were tested using a temporal bisection task with sub-second and supra-second durations. The data were divided into two samples. In the first sample, all participants were integrated into the analysis regardless of their success. In the second sample, only performers were inserted. The point of subjective equality (PSE) and the Weber Ratio (WR) were analyzed for each participant in each sample. By fitting a mathematical model to these parameters as a function of age, we showed a large inter-individual variability in the PSE, such that it does not stabilize with increasing age, i.e., during the significant period of development. Interestingly, time sensitivity (WR) shows a similar pattern through the two samples as adult-like performance appeared at an earlier age for short than for long durations. For the first sample, the modeling of WR data suggests that the children reached an adult-like time sensitivity at the age of six years for the short durations and 8½ years for the long durations. For the second sample, the developmental curve was stable at about the same age for the long duration (seven years), and at earlier age for the short durations, i.e., before three years.

The Effect of Emotional Spoken Words on Time Perception Depends on the Gender of the Speaker

The aim of the present study was to investigate the influence of the emotional content of words marking brief intervals on the perceived duration of these intervals. Three independent variables were of interest: the gender of the person pronouncing the words, the gender of participants, and the valence (positive or negative) of the words in conjunction with their arousing properties. A bisection task was used and the tests, involving four different combinations of valence and arousing conditions (plus a neutral condition), were randomized within trials. The main results revealed that when the valence is negative, participants responded ‘short’ more often when words were pronounced by women rather than by men, and this effect occurred independently of the arousal condition. The results also revealed that overall, males responded ‘longer’more often than females. Finally, in the negative and low arousal condition, the Weber ratio was higher (lower sensitivity) when a male voice was used than when a female voice was used. This study shows that the gender of the person producing the stimuli whose duration is to be judged should be taken into account when analyzing the effect of emotion on time perception.

Executive processes and timing: Comparing timing with and without reference memory

Temporal perception is influenced by executive function. However, performance on different temporal tasks is often associated with different executive functions. This study examined whether using reference memory during a task influenced how performance was associated with executive resources. Participants completed temporal generalisation and bisection tasks, in their normal versions involving reference memory and in episodic versions without reference memory. Each timing task had two difficulty levels: easy and hard. Correlations between performance on these tasks and measures of executive function (updating, inhibition, task switching, and access to semantic memory) were assessed. Accuracy on the temporal generalisation task was correlated with memory access for all versions of the task. Updating correlated with accuracy only for the reference memory-based version of the task. Temporal bisection performance presented a different pattern of correlations. The bisection point was negatively correlated with inhibition scores, except for the easy episodic condition. The Weber ratio, considered a measure of temporal sensitivity, was negatively correlated with memory access only in the hard episodic condition. Together, the findings suggest that previous models of generalisation and bisection may not accurately reflect the underlying cognitive processes involved in the tasks.

Stronger cortisol response to acute psychosocial stress is correlated with larger decrease in temporal sensitivity

As a fundamental dimension of cognition and behavior, time perception has been found to be sensitive to stress. However, how one’s time perception changes with responses to stress is still unclear. The present study aimed to investigate the relationship between stress-induced cortisol response and time perception. A group of 40 healthy young male adults performed a temporal bisection task before and after the Trier Social Stress Test for a stress condition. A control group of 27 male participants completed the same time perception task without stress induction. In the temporal bisection task, participants were first presented with short (400 ms) and long (1,600 ms) visual signals serving as anchor durations and then required to judge whether the intermediate probe durations were more similar to the short or the long anchor. The bisection point and Weber ratio were calculated and indicated the subjective duration and the temporal sensitivity, respectively. Data showed that participants in the stress group had significantly increased salivary cortisol levels, heart rates, and negative affects compared with those in the control group. The results did not show significant group differences for the subjective duration or the temporal sensitivity. However, the results showed a significant positive correlation between stress-induced cortisol responses and decreases in temporal sensitivity indexed by increases in the Weber ratio. This correlation was not observed for the control group. Changes in subjective duration indexed by temporal bisection points were not correlated with cortisol reactivity in both the groups. In conclusion, the present study found that although no significant change was observed in time perception after an acute stressor on the group-level comparison (i.e., stress vs. nonstress group), individuals with stronger cortisol responses to stress showed a larger decrease in temporal sensitivity. This finding may provide insight into the understanding of the relationship between stress and temporal sensitivity.

A new car following model from the perspective of visual imaging

The paper proposes a car following model from the perspective of visual imaging (VIM), where the visual imaging size of the preceding vehicle on a driver's retina is considered as the stimuli and determines the driving behaviors. NGSIM trajectory data are applied to calibrate and validate the VIM under two scenarios, i.e. following the car and following the truck, whose fitting performance outperforms that of visual angle car following model (VAM). Through linear stability analyses for VIM, it can be drawn that the asymmetry in traffic flow is preserved; the larger vehicle width, vehicle length and vehicle apparent size all benefit enlarging the traffic flow stable region; the traffic flow unstable region when following the car tends to fall in the relatively small distance headway range compared with that when following the truck. After that, numerical experiments demonstrate that the visual imaging information applied in VIM is more contributive to the traffic flow stability than the visual angle information in VAM when following the truck in the relatively large distance headway or involving the driver's perception threshold, i.e. Weber ratio; introducing Weber ratio would break the originally stable traffic flow or deteriorate the traffic fluctuation, which however can be alleviated by increasing drivers' sensitivity, e.g., decreasing Weber ratio. Finally, VIM is verified to be able to satisfy the consistency criteria well from the theoretical aspect.