Showing papers on "Time perception published in 2002"
TL;DR: The findings suggest that children with ADHD perform poorly on time reproduction tasks which load heavily on impulsiveness and attentional processes and they suggest that these children may have a perceptual deficit of time discrimination, which may only be detectable in brief durations which differ by several hundred milliseconds.
Abstract: Background: Deficits have been found previously in children with ADHD on tasks of time reproduction, time production and motor timing, implicating a deficit in temporal processing abilities, which has been interpreted as either secondary or primary to core executive dysfunctions. The aim of this study was to explore further the abilities of hyperactive children in skills of time estimation, using a range of time perception tasks in different temporal domains. Method: Time estimation was tested in a verbal estimation task of 10 seconds. Time reproduction was also acquired for two time intervals of 5 and 12 seconds. A temporal discrimination task aimed to determine the idiosyncratic threshold of minimum time interval (in milliseconds) necessary to distinguish two intervals differing by approximately 300 milliseconds. Twenty-two children diagnosed with ADHD were compared to 22 healthy children, matched for age, handedness and working memory skills. Results: Children with ADHD were significantly impaired in their time discrimination threshold: on average, time intervals had to be 50 ms longer for the hyperactive children in order to be discriminated when compared with controls. Children with ADHD also responded earlier on a 12-second reproduction task, which however only approached significance after controlling for IQ and short-term memory. No group differences were found for the 5-second time reproduction or verbal time estimation tasks. Conclusions: The findings suggest that children with ADHD perform poorly on time reproduction tasks which load heavily on impulsiveness and attentional processes and they also suggest that these children may have a perceptual deficit of time discrimination, which may only be detectable in brief durations which differ by several hundred milliseconds. A temporal perception deficit in the range of milliseconds in ADHD may impact upon other functions such as perceptual language skills and motor timing.
302 citations
TL;DR: The attentional modulation of sensory neurons reflects a subject's anticipation of the timing of behaviourally relevant events and is shown to reflect the allocation of attention over time.
Abstract: Paying attention to a stimulus selectively increases the ability to process it. For example, when subjects attend to a specific region of a visual scene, their sensitivity to changes at that location increases. A large number of studies describe the behavioural consequences and neurophysiological correlates of attending to spatial locations. There has, in contrast, been little study of the allocation of attention over time. Because subjects can anticipate predictable events with great temporal precision, it seems probable that they might dynamically shift their attention when performing a familiar perceptual task whose constraints changed over time. We trained monkeys to respond to a stimulus change where the probability of occurrence changed over time. Recording from area V4 of the visual cortex in these animals, we found that the modulation of neuronal responses changed according to the probability of the change occurring at that instant. Thus, we show that the attentional modulation of sensory neurons reflects a subject's anticipation of the timing of behaviourally relevant events.
288 citations
TL;DR: The optimisation of behaviour by attention can be achieved as a consequence of distinct modulatory processes, illustrating the flexibility of attentional functions in the human brain.
172 citations
TL;DR: The delay of the offset of the sustained field was found to increase with interclick interval up to 200 ms at least, which suggests that the sustainedField offset represents a sophisticated offset-monitoring mechanism rather than simply the cessation of stimulation.
157 citations
TL;DR: The results suggest that a large portion of disabled readers suffer from diverse difficulties in auditory processing, though increased within-channel noise is consistent with the majority of the deficits found in the subgroup of poorer auditory processors.
Abstract: The nature of the auditory processing deficit of disabled readers is still an unresolved issue. The quest for a fundamental, nonlinguistic, perceptual impairment has been dominated by the hypothesis that the difficulty lies in processing sequences of stimuli at presentation rates of tens of milliseconds. The present study examined this hypothesis using tasks that require processing of a wide range of stimulus time constants. About a third of the sampled population of disabled readers (classified as "poor auditory processors") had difficulties in most of the tasks tested: detection of frequency differences, detection of tones in narrowband noise, detection of amplitude modulation, detection of the direction of sound sources moving in virtual space, and perception of the lateralized position of tones based on their interaural phase differences. Nevertheless, across-channel integration was intact in these poor auditory processors since comodulation masking release was not reduced. Furthermore, phase locking was presumably intact since binaural masking level differences were normal. In a further examination of temporal processing, participants were asked to discriminate two tones at various intervals where the frequency difference was ten times each individual's frequency just noticeable difference (JND). Under these conditions, poor auditory processors showed no specific difficulty at brief intervals, contrary to predictions under a fast temporal processing deficit assumption. The complementary subgroup of disabled readers who were not poor auditory processors showed some difficulty in this condition when compared with their direct controls. However, they had no difficulty on auditory tasks such as amplitude modulation detection, which presumably taps processing of similar time scales. These two subgroups of disabled readers had similar reading performance but those with a generally poor auditory performance scored lower on some cognitive tests. Taken together, these results suggest that a large portion of disabled readers suffer from diverse difficulties in auditory processing. No parsimonious explanation based on current models of low-level auditory processing can account simultaneously for all these results, though increased within-channel noise is consistent with the majority of the deficits found in the subgroup of poorer auditory processors.
153 citations
TL;DR: The findings suggest that the integrity of the right hemisphere seems to be critical for temporal reproduction of intervals longer than 2-3 s, and that patients with right-hemispheric lesions appear to be impaired in reproductions of stimuli longer than 1-2 s.
118 citations
TL;DR: Discrimination of sound duration, as for discrimination of sound intensity, involves two cerebral networks: a supramodal right fronto-parietal cortical network responsible for allocation of sensory attentional resources, and a network of regions such as the basal ganglia, cerebellum, and right prefrontal cortex, more specifically involved in the temporal aspects of the discrimination task.
112 citations
TL;DR: The case of a patient who had a selective impairment in the perception of events’ duration is described, a 49-year-old man who reported mental confusion and difficulty with concentration and Neurologic examination showed very mild left hemiparesis that regressed in a few days.
Abstract: The neural systems underlying subjective perception of time are of increasing interest for neuroscientists. Previous studies in humans and in animals have documented a role of the cerebellum and basal ganglia as an internal clock of discrete temporal units.1,2⇓ Recent data from focal lesion investigations have suggested that the frontal and the parietal lobes also are critical for time perception, especially for their role in attention and in maintaining the representation of subjective time in the working memory.3,4⇓ Neuropsychological and functional imaging studies have supported the importance of the prefrontal cortex in the perception and in the comparison of time intervals.5
We describe the case of a patient who had a selective impairment in the perception of events’ duration.
A 49-year-old man reported mental confusion and difficulty with concentration. Neurologic examination showed very mild left hemiparesis that regressed in a few days. After this acute episode, …
108 citations
TL;DR: The results reveal that, in addition to reduced audibility of slow and fast envelope cues, some dyslexic children show poor encoding fidelity for these cues (as measured by the discrimination tasks).
Abstract: Speech intelligibility depends heavily on the accurate perception of auditory temporal envelope cues, that is the slower amplitude modulations present in the speech waveform. In a previous study, McAnally and Stein demonstrated that dyslexics may show impaired audibility (i.e. detectability) of thes
75 citations
TL;DR: Results were independent of the presence of ADHD and suggest that children with RD have a deficit in phoneme perception that correlates with reading and phonological processing ability.
73 citations
TL;DR: Judgement of time showed that the auditory system is also susceptible to chronostasis, which is consistent with theories of time perception that emphasize a single, multimodal clock for duration estimation rather than a mechanism that is dependent on motor acts.
TL;DR: Time estimation data suggest that patients with schizophrenia exhibit deficits in differentiating subtle differences in intervals in the tens of milliseconds range, compared to their normal control peers on both auditory and visual perception tasks.
Abstract: Introduction. Characteristics of time perception have not been well documented in patients with schizophrenia. The current study investigated time estimation to (1) test whether visual and auditory time perception varied between patients and controls, (2) assess the degree to which patients and controls can differentiate changes in experimental intervals, and (3) explore whether the temporal deficits suggest a general time perception deficit versus modality-specific differences. Methods. Participants were asked to decide whether temporal intervals were shorter or longer than standard intervals on computer-based auditory and visual temporal perception tasks. Data are presented for a sample of 10 patients with schizophrenia and 10 normal controls. Results. Data suggest that patients with schizophrenia exhibit deficits in differentiating subtle differences in intervals in the tens of milliseconds range, compared to their normal control peers on both auditory (p <.01) and visual perception tasks (p <.01). Con...
TL;DR: Functional MRI data from Thai and English subjects collected in a speeded-response, selective attention paradigm demonstrate that encoding of complex auditory signals is influenced by their functional role in a particular language.
TL;DR: In this paper, the effect of attentional distraction on temporal bisection performance in 5-and 8-year-old children was investigated. But the effect was not as strong in the 8-and 5-year olds.
Abstract: The purpose of the present study was to test the effect of attentional distraction on temporal bisection performance in 5- and 8-year-old children. During a first learning phase, children were trained to discriminate on a temporal bisection task a short standard duration (2 sec) from a long one (8 sec), presented as visual stimuli. Later, in a second testing phase, intermediate durations (3, 4, 5, 6, 7 s), including the standard durations, were presented. Children's task still was to report if it was a short standard duration or a long one. In addition, during the non-standard duration, a distracter either did or did not appear. Results showed increasing proportions of “it is the long standard duration” (response “long”) with increasing stimulus durations in both distracter and non-distracter conditions. However, psychophysical functions were flatter in the 5-year-olds than in the 8-year-olds, revealing their lower sensibility to time. Nevertheless, the 5-year-olds' proportion of long responses was higher...
TL;DR: The temporal granularity of consciousness may be far less fine than the real-time information processing mechanisms that underlie the authors' sensitivity to small temporal differences.
TL;DR: The results suggest that perception of deviations from regularity engages context-sensitive timing processes, probably related to conscious awareness, that are not involved in sensorimotor synchronization.
Abstract: In three experiments, the effects of contextual temporal variation on the perception of timing and on sensorimotor synchronization were examined. Experiment 1 showed that exposure to a variably timed auditory precursor sequence reduces the detectability of deviations from isochrony in a musical test sequence. By contrast, in Experiment 2 there was only a small and transient effect of identical precursor sequences on the variability of finger taps that were synchronized with a similar test sequence. Moreover, the precursor did not impede phase error correction following deviations from isochrony in the test sequence. Experiment 3 employed a within-subjects design that required simultaneous detection of irregularities in and synchronization with nonmusical auditory sequences. Precursor variability impaired only detection, not synchronization performance. These results suggest that perception of deviations from regularity engages context-sensitive timing processes, probably related to conscious awareness, that are not involved in sensorimotor synchronization.
TL;DR: Two experiments indicate that prospective judgments of a temporal target are influenced by nontarget temporal features, and show that the duration of an irrelevant cue can influence judgment of the target interval, as if it were also timed without appropriate control.
TL;DR: Patients with auditory extinction perceived two acoustic events as being 'simultaneous' when the contralesional sound was leading by 270 ms, and the magnitude of this asynchrony was quite similar to that measured previously in the visual modality.
TL;DR: The appeal to differences in physiological latency to explain the FLE runs the risk of oversimplification, given the many shortcomings that hypothesis must contend with.
TL;DR: In this article, the authors incorporate the evidence for a rate-biased subjective time perception into a classic model of optimal foraging, the marginal value theorem, and show that animals follow the predictions of this model exactly.
Journal Article•
TL;DR: Time estimation was tested in young adults screened for attention deficit, based on scores of a self-report questionnaire for attention problems, using a prospective reproduction paradigm suggesting that males with attention deficits and both groups of females made larger underestimations of time judgement than control males.
TL;DR: Individual response variability, group response variability and response magnitude represent dissociable features of performance on these time perception tasks and KR provides guidance for these behaviors.
TL;DR: In this article, the authors investigated the relationship between Eysenck's basic dimensions of personality and performance on temporal processing of auditory intervals in the range of milliseconds (i.e. time perception) and seconds (e.g. time estimation) and found that performance on time estimation was significantly associated with the personality dimension of psychoticism.
TL;DR: A review of studies on age-related changes concerning slowing of an internal timekeeping mechanism, effects of attentional and memory deficits on temporal processing, and effects of practice in preserving accurate rhythmic performance can be found in this article.
Abstract: The capacity to perceive and produce rhythmic patterns accurately is an important element of musical skill. As people age, deficits in some cognitive functions may lead to less accurate rhythmic performance. This article reviews studies on age-related changes concerning slowing of an internal timekeeping mechanism, effects of attentional and memory deficits on temporal processing, and effects of practice in preserving accurate rhythmic performance. The assumption of a slower pacemaker in older people is supported by experiments using isochronous tasks. Slowing in polyrhythmic tasks, implicating the role of attentional workload factors, suggests that timing in music involves more than automatic processes. Studies of the estimation of short temporal intervals generally converge to show that temporal judgments of elderly are less accurate than those of young adults, particularly in attentional sharing conditions. Mere changes in the rate of the internal timekeeping mechanisms are insufficient to explain those results and suggest an interaction between more general changes in cognitive processes, such as reduction in attentional resources, and deficits in working-memory. Studies of the benefits of continued practice in older professional musicians demonstrate that high levels of experience and practice preserve accurate rhythmic performance, thus partially compensating for age-related decline in processing speed and memory. Temporal and Nontemporal Information Processing in Music Music often is considered the "art of time." Indeed, "time enters into both the production and perception of musical events" (Jones, 1990, p. 213). Music perception and performance as cognitively demanding activities require that several categories of information be simultaneously processed. Some of them are more related to temporal processes than others, for example, rhythm versus melody. Musical time speaks to traditional psychological issues that are concerned with the production and perception of time. A number of researchers studying psychological time (Church, 1984;Michon, 1972;Treisman, 1963) have proposed that temporal information processing in humans is subserved by an internal clock-like mechanism. According to the internal clock model, time perception relies on an accumulation process, activated when the subject attends to time, and which counts the number of pulses produced by means of an internal time base during the interval to be evaluated. This model accounts principally for perception of the duration of external stimuli. Wing and Kristofferson (1973) proposed a two-process model to account for the performance of rhythmic tapping: An internal timekeeper emits pulses (timing process), each of which triggers a motor response (motor process). Thus the production of time intervals depends not only on actual physical duration but also on a variety of nontemporal factors, such as those related to motor implementation, Similarly, duration judgments cannot center on use of abstracted and isolated time intervals. For example, the so-called "filled interval effect" reveals that two identical time intervals may be perceived as different because of the information that fills them. This effect emphasizes the influence of nontemporal information on time judgments. Generally, studies examining the relationship between nontemporal factors and time perception and production often lead to different and contradictory results. The great variety of methodological approaches often makes the comparison of findings difficult. Nevertheless, good agreement exists between researchers that the judgment of duration cannot only be accounted for in terms of biological clocks or pacemakers and that a number of cognitive variables could affect a putative biological mechanism. As stressed by Craik and Hay ( 1999), a reasonable middle ground can be found in current models that embrace both biological and psychological factors. Thus, "attentional" models, which are basically extensions of models postulating the existence of an internal timer (pacemaker-accumulator), add an attentional component, assuming that the internal timer requires attention to operate (B lock & Zakay, 1996; Zakay, 1989). …
TL;DR: It was examined whether stimulus modality affects the retrieval of subjective duration from memory and found discrimination was more accurate if the training and testing stimuli were of the same modality than if they were of opposite modalities.
TL;DR: A new study has reported a seemingly related phenomenon --chronostasis---in which one's perception of time also undergoes an illusory distortion during rapid movements of the eyes.
01 Nov 2002
TL;DR: Why the older the authors get, the more they perceive the speed of time to increase-there is a clinical reason for this nature-related aging phenomenon, and it is shown that nurture-related or experiential factors can also affect their perception of time.
Abstract: "I don't believe it: another year has flown by-it seems that time is going by at an ever-faster rate." This often-expressed perception of time, actually the speed of time, is both qualitatively and quantitatively explored herein. While the speed of time is clearly invariant (at least on earth and at speeds that are orders of magnitude below the speed of light), there is ample and plausible evidence that serves to contribute to our perception of a faster moving time. More specifically, it seems that both nature and nurture impact or influence our perception of time, in particular, the speed of time. In this paper, we briefly review the cognitive and related literature to understand why the older we get, the more we perceive the speed of time to increase-there is a clinical reason for this nature-related aging phenomenon. We then show that nurture-related or experiential factors can also affect our perceived speed of time. More specifically, time series data that concern factors which impact our daily lives can be used to model or correlate with our perception of time. It is suggested that nurture reinforces and about doubles nature's impact; that is, the older we get, the more we perceive time to be speeding up. Interestingly, when age is controlled, the experiential data suggests, for example, that a 62-year-old in 1997 perceived time to be about 7.69 times as fast as that perceived by a 62-year-old in 1897; this phenomenon is less extreme for younger aged persons. Finally, it should be noted that understanding the way we perceive the speed of time over time is not only an important endeavor in its own right, but it also has a potentially significant impact on our ability to cope, on our work productivity, on our lifestyle, indeed on all aspects of our life.