Testing some implications of the sensory physiological model of the time sense

Summary In this paper some implications of the pulse generator model of time perception have been tested. In the case of serial (re)production of an interval a lengthening effect occurs. Generally, this phenomenon is explained by assuming that the time-keeper is driven by the state of general physiological activation which decreases in the course of the task. An experiment was carried out in which EEG activity was recorded during the time estimation process. It appeared that a lengthening effect occurred, but there was no correlation between the reproduction times and the means of the EEG spectra, however. In a second experiment two series of time estimations were compared as a function of administering a placebo and methamphetamine. In the latter case the model predicts that no lengthening will occur since arousal (at least for a short period of time) is kept at a high and constant level. In fact, no differences between the regressions of the time estimation curves before and after drug administration have been found, so that the predictions of the model as regards the origin of lengthening could not be supported. It is suggested that the nature of the effect should be studied within the framework of the cognitive theory of time experience which offers various starting points in this respect.     

Sequential estimations of time

Sequential estimations of intervals stored and reproduced by either counting or not counting are compared in experiments with single and repeated presentation of the standard interval. In a non-counting condition the estimates show a negative correlation with the last occurring trial throughout the series after one presentation of the standard. Consequently, in an ongoing process the capacity for (the storage and) the recall of time appears to be limited to the most recent event corresponding with the previous estimate. Correlations are lacking when the standard is presented after every estimate because the most recent information is an external constant. The correlations with the last trial recur when relatively long intervals are used, stored on the basis of various sensory cues. When the difference between the number of these cues is minimized, the correlation disappears. Counting never shows sequential correlations since it favors the coding and storage of time as a number of subjective units. The temporal equivalent of that number is constructed from trial to trial, a representation of the complete interval is not available and the subject does not remember his counting rate.     

A Comparison of the Cross-Sectional and Sequential Designs when Assessing Longitudinal Mediation

Mediational studies are often of interest in psychology because they explore the underlying relationship between 2 constructs. Previous research has shown that cross-sectional designs are prone to biased estimates of longitudinal mediation parameters. The sequential design has become a popular alternative to the cross-sectional design for assessing mediation. This design is a compromise between the cross-sectional and longitudinal designs because it incorporates time in the model but has only 1 measurement each of X, M, and Y. As such, this design follows the recommendation of the MacArthur group approach, which stresses the importance of multiple waves of data for studying mediation. These 2 designs were compared to see whether the sequential design assesses longitudinal mediation more accurately than the cross-sectional design. Specifically, analytic expressions are derived for the bias of estimated direct and indirect effects as calculated from the sequential design when the actual mediational process follows a longitudinal autoregressive model. It was found that, in general, the sequential design does not assess longitudinal mediation more accurately than the cross-sectional design. As a result, neither design can be depended on to assess longitudinal mediation accurately.     

时距估计中的锚定效应

采用两种时距估计方法,检验时距锚定值对时距估计的影响,并探讨了时距信息的心理表征方式。63名在校大学生参加了本次实验。实验1采用口头报告法,表明较大的时距锚定值（5s,5000ms）条件下,被试估对时距的估计值较大,而较小时距锚定值（1s,1000ms）条件下被试估计的时距值较小;语义相同但表述方式不同的锚定值（1s与1000ms,5s与5000ms）条件下的时距估计值没有显著差异。实验2采用产生法,进一步表明时距表述方式对产生时距没有显著影响。以上结果表明,时距估计受时距锚定值的影响,时距信息可能以语义形式进行表征,而不是简单的数字加单位的表层表征形式     

Hindsight bias after receiving self-relevant health risk information: a motivational perspective

The phenomenon of hindsight bias was explored in the context of self-relevant health risk information. Participants in a community screening estimated their cholesterol level (foresight measure) before receiving positive or negative feedback based on their actual cholesterol level. Hindsight estimations were then assessed twice: once immediately after the feedback, and again several weeks later. While the unexpected positive feedback group showed no systematic recall bias, hindsight estimations of individuals receiving unexpectedly negative feedback showed a dynamic change over time. Immediately after the feedback, participants' recollection of their expected cholesterol level were shifted towards their actual cholesterol level (hindsight bias). In contrast, several weeks later, foresight estimations were recalled as less accurate than they had been (reversed hindsight bias). These data might reflect a change of the motivational focus from "hot affect" and fear control, which occur immediately after receiving negative feedback, to danger control, which occurs some time after the feedback, as proposed by the dual process model.     

Hindsight bias after receiving self-relevant health risk information: A motivational perspective

The phenomenon of hindsight bias was explored in the context of self-relevant health risk information. Participants in a community screening estimated their cholesterol level (foresight measure) before receiving positive or negative feedback based on their actual cholesterol level. Hindsight estimations were then assessed twice: once immediately after the feedback, and again several weeks later. While the unexpected positive feedback group showed no systematic recall bias, hindsight estimations of individuals receiving unexpectedly negative feedback showed a dynamic change over time. Immediately after the feedback, participants' recollection of their expected cholesterol level were shifted towards their actual cholesterol level (hindsight bias). In contrast, several weeks later, foresight estimations were recalled as less accurate than they had been (reversed hindsight bias). These data might reflect a change of the motivational focus from "hot affect" and fear control, which occur immediately after receiving negative feedback, to danger control, which occurs some time after the feedback, as proposed by the dual process model.     

The time-saving bias, speed choices and driving behavior

When drivers are asked to estimate how much time can be saved by increasing speed, they generally underestimate the time saved when increasing from a relatively low speed and overestimate the time saved when increasing from a relatively high speed. This time-saving bias has been demonstrated to affect drivers’ estimations of driving speed as well as drivers’ personal choice of speed. Specifically, drivers with a high time-saving bias chose unduly high speeds, which sometimes results in speeding, more frequently than drivers with a lower degree of the bias. This study sought to determine whether this relationship would be mediated by individual differences in driving behavior – including drivers’ attitudes, norms and habits regarding speeding behavior as well as their level of aberrant driving behavior (committing aggressive or ordinary violations, errors or lapses in driving, measured by the Driver Behaviour Questionnaire). The results showed that the time-saving bias predicted estimations of required speed better than any of these factors, and also better than drivers’ age, gender, education and income, as well as the number of years they have had a license and their monthly driving kilometrage, their prior speeding violations and crash involvement. In predicting drivers’ personal speed choices, the time-saving bias was second only to the frequency of committing ordinary violations.     

Time Perspective: Temporal Extension,Time Estimation,and Impulsivity

It has been proposed that time perspective is an important variable that can, in part, explain the differences between people in terms of the development of self-control. One corollary of this position is that time perspective is somehow related to systematic biases in the way people perceive the passage of time. Such a bias may or may not be augmented by an association between time perspective and impulsivity. Two studies were conducted using measures of temporal extension, time estimation, and impulsivity. In general, no consistent effects were found. Neither time perspective nor impulsivity was related to any characteristic pattern of errors. In the second study, time perspective (mediated by age) was associated with predicting very brief time estimation scores, but not longer time estimation periods. It was concluded that whatever the mechanism might be that underlies the purported effect between time perspective and self-control, it is not related to a differential ability to perceive time moving more or less quickly.     

Investigating the validity of the Perceptual Awareness Scale – The effect of task-related difficulty on subjective rating

The Perceptual Awareness Scale (PAS) is often used to probe conscious experience, but the assumptions behind the scale and its validity are rarely tested. Using a continuous colour estimation task to assess perceptual quality, we focus on how well PAS follows perceptual quality and how the presence of the estimation task affects PAS ratings. We varied the number and presentation time of stimuli in a simultaneous presentation and target position in a sequential presentation. In all experiments, PAS rating closely followed colour precision. However, it was affected by task-induced response bias, even when the possible task difficulty was judged, without performing the task itself. Still, this bias was only observed on the absolute rating level rather than the scale's ability to capture changes in perceptual quality. Reported studies shed light on factors influencing scales outside of the scale formulation and construction.     

Longitudinal changes in time estimation in affective disorders: a preliminary study

8 patients with hospital diagnoses of major affective disorder were studied by repeated measurements of time estimation using the three different methods of metronome adjustment, verbal estimation and operative estimation (production) of short time intervals. Retrospective estimations of longer intervals were also studied. The diagnoses were evaluated according to DSM III criteria. The degree of mental disturbance was rated with subscales of the Comprehensive Psychopathological Rating Scale. Earlier findings had indicated that manic patients tend to overestimate short time intervals and that some depressed patients underestimated time, but some investigators have reported different results. A longitudinal study could possibly support the earlier findings if the time estimations should vary with the clinical states of the patients. Such a variation was suggested by the results of 5 of the 8 patients. In several cases there were statistically significant correlations between the results of time estimations and the rating scores. This partly supports earlier findings. Associations between time estimations and changes in clinical state seem to be present in some cases of major affective disorders. Operative estimations were best correlated with ratings in most cases.     

Size judgment: The presence of a standard increases the exponent of the power law

Ss judged the size of circles by the methods of magnitude estimation and magnitude production, with or without a standard figure present. The presence of the standard raised the exponent of the power law. The effect was largely independent of the position of the standard in the range of stimuli. It is argued that the standard’s effect was not mediated by a difference in apparent size between perceived and remembered standards, a change in Ss’ response strategies, a decrease in sequential dependencies, or other previously identified bias effects.     

Static images with different induced intensities of human body movements affect subjective time

Modulation of subjective time was examined using static images eliciting perceptions of different intensities of body movement. Undergraduate students were exposed to photographs of dancer sculptures in different dance positions for 36 sec. and asked to estimate the exposure duration. Lower movement intensities were related to shorter estimated durations. Mean durations for images of unmoving dancers were underestimated and for dancers taking a ballet step were overestimated. Temporal estimations were also related to the order of presentation of the stimuli, which suggested that subjective time estimations were influenced by the experimental context. Subjective time is related not only to the visual perception of moving images, but also of elicited perceptions of movement in static images, suggesting an embodiment effect on subjective time estimation.     

Asymmetries in visuomotor recalibration of time perception: Does causal binding distort the window of integration?

The recalibration of perceived visuomotor simultaneity to vision-lead and movement-lead temporal discrepancies is marked by an underlying causal asymmetry, if the movement (button press) is voluntary and self-initiated; a visual stimulus lagging the button press may be interpreted as causally linked sensory feedback (intentional or causal binding), a leading visual stimulus not. Here, we test whether this underlying causal asymmetry leads to directional asymmetries in the temporal recalibration of visuomotor time perception, using an interval estimation paradigm. Participants were trained to the presence of one of three temporal discrepancies between a motor action (button press) and a visual stimulus (flashed disk): 100 ms vision-lead, simultaneity, and 100 ms movement-lead. By adjusting a point on a visual scale, participants then estimated the interval between the visual stimulus and the button press over a range of discrepancies. Comparing the results across conditions, we found that temporal recalibration appears to be implemented nearly exclusively on the movement-lead side of the range of discrepancies by a uni-lateral lengthening or shortening of the window of temporal integration. Interestingly, this marked asymmetry does not lead to a significantly asymmetrical recalibration of the point of subjective simultaneity or to significant differences in discriminability. This seeming contradiction (symmetrical recalibration of subjective simultaneity and asymmetrical recalibration of interval estimation) poses a challenge to common models of temporal order perception that assume an underlying time measurement process with Gaussian noise. Using a two-criterion model of the window of temporal integration, we illustrate that a compressive bias around perceived simultaneity (temporal integration) even prior to perceptual decisions about temporal order would be very hard to detect given the sensitivity of the psychophysical procedures commonly used.     

Response Form, Force, And Number: Effects On Concurrent-schedule Performance

Six hens responded on concurrent variable-interval (key-peck) variable-interval (door-push) schedules of reinforcement in which the second-order (fixed-ratio) requirements on the alternatives (Experiment 1) or the required door forces (Experiment 2) were varied. The key-peck and door-push response (measured as fixed-ratio completion) and time data were well described by the generalized matching law. However, the manipulations of fixed-ratio requirement and required response force differed in their effects. The manipulations of fixed-ratio size affected the response and time measures differently, producing fairly constant, multiplicative biases only in terms of response allocation. It was argued that variations in fixed-ratio size necessarily change the time allocated to that response unit, and thus changes in time bias were not necessarily a fundamental effect of changing the ratio. In contrast, the changes in response bias were a fundamental result of changes in ratio size. The response-force manipulations produced similar bias shifts in terms of response and time allocation, but they appeared to combine with relative reinforcement rate to affect choice interactively. Specifically, behavior appeared to be biased towards the least effortful (i.e., key-peck) response, but the increases in door force had a larger effect on bias when the hens were making this response infrequently (on a lean schedule). The different effects of the fixed-ratio and response-force manipulations on concurrent performance were partially accounted for by the differing times required to complete each response unit under those manipulations, but this would not account for the interaction. The interaction would be consonant with increased response effort decreasing the effective value of the associated reinforcement schedule.     

Eliminating subjective biases in judging the loudness of a 1-kHz tone

It is possible to eliminate most of the known subjective biases that affect judgments of sensory magnitude using numbers. Experiments are described which do this, and which also investigate some of the biases. The least biased estimate for doubling the loudness of a 1-kHz tone is found to be about 11.5 dB. This value is still slightly affected by the logarithmic bias, although the bias could be eliminated. It is also affected by the stimulus equalizing bias, produced by the inequality between the finite range of loudnesses to which the ears are sensitive and the infinite range of numbers to which the loudnesses are matched. This last bias cannot be eliminated completely in direct magnitude estimation.     

Bias in memory predicts bias in estimation of future task duration

Both anecdotal accounts and experimental evidence suggest that people underestimate how long it will take them to complete future tasks. A possible reason for this tendency is that people remember tasks as taking less time than they actually did, with these biased memories causing a corresponding bias in prediction. Two experiments were performed to determine whether or not a systematic bias in memory could explain a similar systematic bias in prediction. In support, it was found that (1) the tendency to underestimate future duration disappears when the task is novel, (2) there is similar bias in estimation of both past and future durations, and (3) variables that affect memory of duration, such as level of experience with the task and duration of delay before estimation, affect prediction of duration in the same way. It appears that, at least in part, people underestimate future event duration because they underestimate past event duration.     

Prospective and retrospective time perception are related to mental time travel: Evidence from Alzheimer’s disease

Unlike prospective time perception paradigms, in which participants are aware that they have to estimate forthcoming time, little is known about retrospective time perception in normal aging and Alzheimer’s disease (AD). Our paper addresses this shortcoming by comparing prospective and retrospective time estimation in younger adults, older adults, and AD patients. In four prospective tasks (lasting 30 s, 60 s, 90 s, or 120 s) participants were asked to read a series of numbers and to provide a verbal estimation of the reading time. In four other retrospective tasks, they were not informed about time judgment until they were asked to provide a verbal estimation of four elapsed time intervals (lasting 30 s, 60 s, 90 s, or 120 s). AD participants gave shorter verbal time estimations than older adults and younger participants did, suggesting that time is perceived to pass quickly in these patients. For all participants, the duration of the retrospective tasks was underestimated as compared to the prospective tasks and both estimations were shorter than the real time interval. Prospective time estimation was further correlated with mental time travel, as measured with the Remember/Know paradigm. Mental time travel was even higher correlated with retrospective time estimation. Our findings shed light on the relationship between time perception and the ability to mentally project oneself into time, two skills contributing to human memory functioning. Finally, time perception deficits, as observed in AD patients, can be interpreted in terms of dramatic changes occurring in frontal lobes and hippocampus.     

Human choice in concurrent ratio-interval schedules of reinforcement.

Seven undergraduates participated in a concurrent-choice experiment with monetary reinforcers. Response-independent analogues of variable-interval and variable-ratio schedules were used to assess whether subjects would maximize reinforcement rate. The optimal pattern of behavior, in terms of maximizing reinforcement rate, involved a large bias toward the ratio alternative, with only occasional sampling of the interval schedule. Most experiments with pigeons, however, demonstrate matching of response rates to reinforcement rates, with only slight biases for the ratio schedule. Although subjects in the present experiment allocated more time to the ratio alternative than required by matching, the magnitude of the bias did not approximate that predicted by a maximizing account. After exposure to clock stimuli correlated with the operation of each schedule, 1 subject's behavior did show a substantial level of bias, increasing the total number of reinforcers obtained, and lay at a point between the predictions of matching and maximizing. The other subjects, however, continued to respond less optimally. The present results can be accounted for by a view of matching that incorporates the effects of delayed reinforcement.     

Expecting a break in time estimation: attentional time-sharing without concurrent processing

The interference from nontemporal processing on concurrent time estimation is usually attributed to disruption in timing caused by attentional requirements of nontemporal processing. Here, we examined interruption in timing without concurrent nontemporal processing. Empty breaks of various durations, during time-interval production, lengthened produced intervals. Moreover, an effect of break location was observed: Intervals lengthened proportionally to prebreak duration. When cued and uncued uninterrupted trials were introduced, the lengthening was proportional to the duration for which a break was expected. It was concluded that attentional time-sharing between time estimation and expectation of its interruption contributed to the interference effect in time-estimation research, independently of any concurrent processing requirements during time estimation.     

Learning effects of knowledge of results upon time estimation

College students of both sexes served as their own controls to test three hypotheses in each of two separate experiments designed to assess the learning effects of knowledge of results upon time estimation. The results indicated that (1) knowledge of results in the form of feedback to the nearest hundredth of a second significantly increased the mean accuracy of time estimations obtained by the method of production, (2) that knowledge of results significantly decreased the variance of the time estimations, and (3) that sex difference as a main effect was not significant in either experiment. A major conclusion of the present study was that variance represents an authentic and independent measure of learning.