Showing papers on "Time perception published in 2007"
TL;DR: It is outlined how these new findings can be explained within the framework of internal-clock models and described how emotional arousal and valence interact to produce both increases and decreases in attentional time sharing and clock speed.
601 citations
TL;DR: An alternate model in which cortical networks are inherently able to tell time as a result of time-dependent changes in network state is examined, showing that within this framework, there is no linear metric of time, and that a given interval is encoded in the context of preceding events.
513 citations
TL;DR: The results suggest that the posterior insula, which is a critical component of the decision-making neural network, is involved in delaying gratification and the degree of neural activation in the striatum, which plays a fundamental role in reward prediction and in time estimation, may code for the time delay.
Abstract: Delay discounting refers to the fact that an immediate reward is valued more than the same reward if it occurs some time in the future. To examine the neural substrates underlying this process, we studied 13 healthy volunteers who repeatedly had to decide between an immediate and parametrically varied delayed hypothetical reward using a delay discounting task during event-related functional magnetic resonance imaging. Subject’s preference judgments resulted in different discounting slopes for shorter (<1 year) and for longer (≥1 year) delays. Neural activation associated with the shorter delays relative to the longer delays was associated with increased activation in the head of the left caudate nucleus and putamen. When individuals selected the delayed relative to the immediate reward, a strong activation was found in bilateral posterior insular cortex. Several brain areas including the left caudate nucleus showed a correlation between the behaviorally determined discounting and brain activation for the contrast of intervals with delays <1 and ≥1 year. These results suggest that (1) the posterior insula, which is a critical component of the decision-making neural network, is involved in delaying gratification and (2) the degree of neural activation in the striatum, which plays a fundamental role in reward prediction and in time estimation, may code for the time delay.
254 citations
TL;DR: Emotional and neutral sounds rated for valence and arousal were used to investigate the influence of emotions on timing in reproduction and verbal estimation tasks, suggesting that both activation and attentional processes modulate the timing of emotional events.
Abstract: Emotional and neutral sounds rated for valence and arousal were used to investigate the influence of emotions on timing in reproduction and verbal estimation tasks with durations from 2 s to 6 s. Results revealed an effect of emotion on temporal judgment, with emotional stimuli judged to be longer than neutral ones for a similar arousal level. Within scalar expectancy theory (J. Gibbon, R. Church, & W. Meck, 1984), this suggests that emotion-induced activation generates an increase in pacemaker rate, leading to a longer perceived duration. A further exploration of self-assessed emotional dimensions showed an effect of valence and arousal. Negative sounds were judged to be longer than positive ones, indicating that negative stimuli generate a greater increase of activation. High-arousing stimuli were perceived to be shorter than low-arousing ones. Consistent with attentional models of timing, this seems to reflect a decrease of attention devoted to time, leading to a shorter perceived duration. These effects, robust across the 2 tasks, are limited to short intervals and overall suggest that both activation and attentional processes modulate the timing of emotional events.
252 citations
TL;DR: It is shown that when a sound or visual flickers is presented in conjunction with an unexpected visual stimulus, neither the pitch of the sound nor the frequency of the flicker is affected by the apparent duration dilation, demonstrating that subjective time in general is not slowed; instead, duration judgments can be manipulated with no concurrent impact on other temporal judgments.
Abstract: Events can sometimes appear longer or shorter in duration than other events of equal length. For example, in a repeated presentation of auditory or visual stimuli, an unexpected object of equivalent duration appears to last longer. Illusions of duration distortion beg an important question of time representation: when durations dilate or contract, does time in general slow down or speed up during that moment? In other words, what entailments do duration distortions have with respect to other timing judgments? We here show that when a sound or visual flicker is presented in conjunction with an unexpected visual stimulus, neither the pitch of the sound nor the frequency of the flicker is affected by the apparent duration dilation. This demonstrates that subjective time in general is not slowed; instead, duration judgments can be manipulated with no concurrent impact on other temporal judgments. Like spatial vision, time perception appears to be underpinned by a collaboration of separate neural mechanisms that usually work in concert but are separable. We further show that the duration dilation of an unexpected stimulus is not enhanced by increasing its saliency, suggesting that the effect is more closely related to prediction violation than enhanced attention. Finally, duration distortions induced by violations of progressive number sequences implicate the involvement of high-level predictability, suggesting the involvement of areas higher than primary visual cortex. We suggest that duration distortions can be understood in terms of repetition suppression, in which neural responses to repeated stimuli are diminished.
242 citations
TL;DR: A theory of prospective time perception is introduced and incorporated as a module in an integrated theory of cognition, thereby extending existing theories and allowing predictions about attention and learning.
Abstract: A theory of prospective time perception is introduced and incorporated as a module in an integrated theory of cognition, thereby extending existing theories and allowing predictions about attention and learning. First, a time perception module is established by fitting existing datasets (interval estimation and bisection and impact of secondary tasks on attention). The authors subsequently used the module as a part of the adaptive control of thought--rational (ACT-R) architecture to model a new experiment that combines attention, learning, dual tasking, and time perception. Finally, the model predicts time estimation, learning, and attention in a new experiment. The model predictions and fits demonstrate that the proposed integrated theory of prospective time interval estimation explains detailed effects of attention and learning during time interval estimation.
221 citations
TL;DR: It is argued that the extent of the timing "network" has been significantly over-estimated in the past and that only these three relatively small regions can safely be regarded as being directly concerned with duration judgements.
220 citations
TL;DR: It is determined that the cerebellum is essential in explicit temporal processing of millisecond time intervals using repetitive transcranial magnetic stimulation (rTMS), and cerebellar involvement in millisecondsond time processing was evident when the time intervals were encoded but not when they were retrieved from memory.
Abstract: Time processing is important in several cognitive and motor functions, but it is still unclear how the human brain perceives time intervals of different durations. Processing of time in millisecond and second intervals may depend on different neural networks and there is now considerable evidence to suggest that these intervals are possibly measured by independent brain mechanisms. Using repetitive transcranial magnetic stimulation (rTMS), we determined that the cerebellum is essential in explicit temporal processing of millisecond time intervals. In the first experiment, subjects' performance in a time reproduction task of short (400-600 ms) and long (1,600-2,400 ms) intervals, were evaluated immediately after application of inhibitory rTMS trains over the left and right lateral cerebellum (Cb) and the right dorsolateral prefrontal cortex (DLPFC). We found that rTMS over the lateral cerebellum impaired time perception in the short interval (millisecond range) only; for the second range intervals, impaired timing was found selectively for stimulation of the right DLPFC. In the second experiment, we observed that cerebellar involvement in millisecond time processing was evident when the time intervals were encoded but not when they were retrieved from memory. Our results are consistent with the hypothesis that the cerebellum can be considered as an internal timing system, deputed to assess millisecond time intervals.
202 citations
TL;DR: This study is the first to systematically assess the impact of psilocybin on timing performance on standardized measures of temporal processing, and indicates that the serotonin system is selectively involved in duration processing of intervals longer than 2 to 3 seconds and in the voluntary control of the speed of movement.
Abstract: Hallucinogenic psilocybin is known to alter the subjective experience of time. However, there is no study that systematically investigated objective measures of time perception under psilocybin. Therefore, we studied dose-dependent effects of the serotonin (5-HT)(2A/1A) receptor agonist psilocybin (4-phosphoryloxy-N,N-dimethyltryptamine) on temporal processing, employing tasks of temporal reproduction, sensorimotor synchronization and tapping tempo. To control for cognitive and subjective changes, we assessed spatial working memory and conscious experience. Twelve healthy human volunteers were tested under placebo, medium (115 mu g/kg), and high (250 mu g/kg) dose conditions, in a double-blind experimental design. Psilocybin was found to significantly impair subjects' ability to (1) reproduce interval durations longer than 2.5 sec, (2) to synchronize to inter-beat intervals Longer than 2 sec and (3) caused subjects to be slower in their preferred tapping rate. These objective effects on timing performance were accompanied by working-memory deficits and subjective changes in conscious state, namely increased reports of 'depersonalization' and 'derealization' phenomena including disturbances in subjective 'time sense.' Our study is the first to systematically assess the impact of psitocybin on timing performance on standardized measures of temporal processing. Results indicate that the serotonin system is selectively involved in duration processing of intervals longer than 2 to 3 seconds and in the voluntary control of the speed of movement. We speculate that psilocybin's selective disruption of longer intervals is likely to be a product of interactions with cognitive dimensions of temporal processing presumably via 5-HT2A receptor stimulation.
166 citations
TL;DR: Altered time processing in SDI could explain why SDI have difficulty delaying gratification, one which can be explained by increased impulsivity.
163 citations
TL;DR: Although timing is more automatic for auditory than visual signals in both children and young adults, children have greater difficulty in keeping the switch in the closed state during the timing of visual signals, consistent with a developmental difference in the operation of the "attentional switch" used to transfer pulses from the pacemaker into the accumulator.
TL;DR: Six experiments are presented in which the relation between numbers and spatial attention was examined using a temporal order judgment task to index attentional allocation, demonstrating that one important consequence of numerical processing is the automatic allocation of spatial attention, which affects the perception of the temporal order of visual events.
TL;DR: This finding suggests that patients may require longer time intervals between two distinct events before being able to perceive them as "one-after-the-other", and the possible involvement of anatomical disconnectivity in schizophrenia which would specifically affect the time integration properties of neural assemblies.
TL;DR: The results indicate that attention can indeed speed up neural processes during visual perception, thereby providing the first electrophysiological support for the existence of prior entry.
Abstract: The speeding-up of neural processing associated with attended events (i.e., the prior-entry effect) has long been proposed as a viable mechanism by which attention can prioritize our perception and action. In the brain, this has been thought to be regulated through a sensory gating mechanism, increasing the amplitudes of early evoked potentials while leaving their latencies unaffected. However, the majority of previous research has emphasized speeded responding and has failed to emphasize fine temporal discrimination, thereby potentially lacking the sensitivity to reveal putative modulations in the timing of neural processing. In the present study, we used a cross-modal temporal order judgment task while shifting attention between the visual and tactile modalities to investigate the mechanisms underlying selective attention electrophysiologically. Our results indicate that attention can indeed speed up neural processes during visual perception, thereby providing the first electrophysiological support for the existence of prior entry.
TL;DR: A pivotal role for a right hemisphere fronto-parietal network in the accurate perception of multisecond durations is suggested, adding to a growing body of literature suggesting that neglect cannot be understood simply in terms of a bias in orienting attention to one side of space.
Abstract: Recent neuroimaging and neuropsychological studies have suggested that the right hemisphere, particularly frontal regions, is important for the perception of the passage of time. We examined the ability to estimate durations of up to 60 sec in a group of eight patients with unilateral neglect. When estimating multisecond intervals, neglect patients grossly underestimated all durations. On average, healthy controls (HC) demonstrated reasonably accurate estimates of all durations tested. Although the right hemisphere lesioned control patients without neglect also tended to underestimate durations, these underestimations were significantly better than the performance of the neglect group. These findings suggest a pivotal role for a right hemisphere fronto-parietal network in the accurate perception of multisecond durations. Furthermore, these findings add to a growing body of literature suggesting that neglect cannot be understood simply in terms of a bias in orienting attention to one side of space. Additional deficits of the kind demonstrated here are likely to be crucial in determining the nature and extent of the loss of conscious awareness for contralesional events.
TL;DR: The bisection procedure may be a useful tool in identifying timing impairments in PD and reaffirm the hypothesised role of the basal ganglia in temporal perception at the level of the attentionally mediated internal clock as well as memory retrieval and/or decision-making processes.
TL;DR: Auditory cortex plasticity associated with short-term perceptual learning was manifested as an enhancement of auditory cortical responses to trained acoustic features only in the trained task and functional plasticity in auditory cortex is here interpreted as the product of bottom-up and top-down modulations.
Abstract: The discrimination of temporal information in acoustic inputs is a crucial aspect of auditory perception, yet very few studies have focused on auditory perceptual learning of timing properties and associated plasticity in adult auditory cortex. Here, we trained participants on a temporal discrimination task. The main task used a base stimulus (four tones separated by intervals of 200 ms) that had to be distinguished from a target stimulus (four tones with intervals down to ∼180 ms). We show that participants' auditory temporal sensitivity improves with a short amount of training (3 d, 1 h/d). Learning to discriminate temporal modulation rates was accompanied by a systematic amplitude increase of the early auditory evoked responses to trained stimuli, as measured by magnetoencephalography. Additionally, learning and auditory cortex plasticity partially generalized to interval discrimination but not to frequency discrimination. Auditory cortex plasticity associated with short-term perceptual learning was manifested as an enhancement of auditory cortical responses to trained acoustic features only in the trained task. Plasticity was also manifested as induced non-phase–locked high gamma-band power increases in inferior frontal cortex during performance in the trained task. Functional plasticity in auditory cortex is here interpreted as the product of bottom-up and top-down modulations.
TL;DR: The results showed that the minimal interval necessary to correctly resolve audiotactile temporal order was larger after Exposure to the desynchronized streams than after exposure to the synchronous streams, suggesting the existence of a mechanism to compensate for audiotactic asynchronies that results in a widening of the temporal window for multisensory integration.
TL;DR: Support is provided for the hypothesis that some timing information is represented in a task-dependent manner across broad cortical and subcortical networks and for a classic prefrontal-parietal-temporal working memory network active only during continuation.
TL;DR: The performance of subjects with cerebellar disease in predictive motor timing is investigated using a task that involved mediated interception of a moving target and the findings demonstrate that the cerebellum may have properties that would facilitate the processing or storage of internal models of motor behavior.
Abstract: The ability to precisely time events is essential for both perception and action. There is evidence that the cerebellum is important for the neural representation of time in a variety of behaviors including time perception, the tapping of specific time intervals, and eye-blink conditioning. It has been difficult to assess the contribution of the cerebellum to timing during more dynamic motor behavior because the component movements themselves may be abnormal or any motor deficit may be due to an inability to combine the component movements into a complete action rather than timing per se. Here we investigated the performance of subjects with cerebellar disease in predictive motor timing using a task that involved mediated interception of a moving target, and we tested the effect of movement type (acceleration, deceleration, constant), speed (slow, medium, fast), and angle (0°, 15° and 30°) on performance. The subjects with cerebellar damage were significantly worse at interception than healthy controls even when we controlled for basic motor impairments such as response time. Our data suggest that subjects with damage to the cerebellum have a fundamental problem with predictive motor timing and indicate that the cerebellum plays an essential role in integrating incoming visual information with motor output when making predictions about upcoming actions. The findings demonstrate that the cerebellum may have properties that would facilitate the processing or storage of internal models of motor behavior.
TL;DR: The results showed that the perceived duration of presentation for apparently larger circles was longer than that of apparently smaller circles, although the actual area remained invariant across all circles, which concluded that the time perception process receives input from later visual processing.
Abstract: National Institute of Advanced Industrial Science and Technology, Tsukuba, Japan The perception of time spent looking at a stimulus is lengthened or shortened when its physical attributes, such as area, differ from those of a comparison stimulus. We measured the perceived presentation duration of a visual object whose apparent area was altered by the Ebbinghaus illusion while its physical size remained invariant, so that a central circle surrounded by larger inducers appeared smaller than a same-size central circle surrounded by smaller inducers. The results showed that the perceived duration of presentation for apparently larger circles was longer than that of apparently smaller circles, although the actual area remained invariant across all circles. We concluded that the time perception process receives input from later visual processing.
TL;DR: Results indicate a directional bias in time perception induced by manipulation of spatial attention and could argue for a mental linear representation of time intervals.
TL;DR: This study provides further support for the existence of a generic time perception deficit, which is probably due to the involvement of a dysfunctional fronto-striato-cerebellar network in this capacity, especially the presence of deficits in basic internal timing mechanisms.
TL;DR: No association between the degree of visual and auditory hemi-inattention was observed amongst the patients, suggesting that there is a certain degree of independence between the mechanisms subserving spatial attention across sensory modalities.
Journal Article•
TL;DR: These findings, documenting for the first time the role of each temporal lobe in duration estimation within the range of minutes, are discussed in light of memory-based and attentional models of time.
Abstract: This study examined the role of medial temporal lobe structures in verbal estimation and production of time intervals Left medial temporal lobe lesions produced deficits in both tasks, whereas right medial temporal lobe lesions only disturbed time production Although both tasks require adequate use of chronometric units, they seem to be subserved by distinct cognitive processing and to depend on different neural substrates Verbal estimation of intervals in retrospect seems to depend mainly on contextual memory, and production of intervals depends more specifically on the mental load devoted to time These findings, documenting for the first time the role of each temporal lobe in duration estimation within the range of minutes, are discussed in light of memory-based and attentional models of time
01 Mar 2007
TL;DR: It will be argued that the functional properties of two different kinds of sensorimotor neurons found in the inferior parietal lobe show the limits and abstractness of any strict dichotomy between perception and action, and pave the way to a requalification of some relevant philosophical perspectives on these issues.
Abstract: For long time perception and action have been considered as separated and peripheral processes, devoid of any intrinsic cognitive value. Over the last years, however, this view has been challenged by several neurophysiological data. The aim of this paper is to provide an overview of some recent studies on the cortical visual and motor systems. In particular, we’ll focus on the discovery (in the inferior parietal lobe and in the premotor cortex) of two different kinds of sensorimotor neurons that not only are involved in the motor control of actions, but also play an essential role in object categorizing and in action understanding.We’ll argue that the functional properties of these kinds of neurons show the limits and abstractness of any strict dichotomy between perception and action, and pave the way to a requalification of some relevant philosophical perspectives on these issues.
TL;DR: Results support the proposition that explicit time information is coded by neural units tuned to specific temporal intervals with broad overlapping tuning curves and it appears that there is a single timing mechanism for each incoming sensory mode, but distinct timers for different modes.
TL;DR: The authors investigated whether the perception of simultaneity for pairs of nociceptive and visual stimuli was dependent upon the focus of participants' attention to a particular sensory modality (either pain or vision).
TL;DR: The results indicate that recorded activity at prefrontal and parietal association cortices is tightly linked to task parameters and behavioral performances.