Subjectivity of time perception: a visual emotional orchestration.

The aim of the present study was to examine how visual emotional content could orchestrate time perception. The experimental design allowed us to single out the share of emotion in the specific processing of content-bearing pictures, i.e.

Time is more than a sensory feature: Attending to duration triggers specific anticipatory activity.

Time processing requires the estimation of events' duration per se, but also seems to trigger attentional and memory processes. To isolate attentional processes, we investigated neural correlates of anticipatory attention when estimating stimulus duration. Magneto-encephalographic (MEG) activity was recorded in fourteen healthy right-handed volunteers, who were cued to attend to either the duration or the intensity of a visual stimulus.

The role of physiological arousal in time perception: psychophysiological evidence from an emotion regulation paradigm.

Time perception, crucial for adaptive behavior, has been shown to be altered by emotion. An arousal-dependent mechanism is proposed to account for such an effect. Yet, physiological measure of arousal related with emotional timing is still lacking.

Ageing affects brain activity in highly educated older adults: An ERP study using a word-stem priming task.

In this event-related evoked potentials (ERP) study, the neural correlates of a group of highly educated older adults were compared with those of a group of young adults while performing a word-stem completion priming task under semantic and lexical encoding conditions. The results revealed that both age groups exhibited robust priming. The older participants showed better performance than the young adults.

ERPs in anterior and posterior regions associated with duration and size discriminations.

The main objective of the present study was to determine whether event-related potentials (ERPs) predominant in prefrontal cortex (PFC) respond in a similar fashion to ERPs predominant in posterior parietal cortex (PPC) in duration and size discrimination tasks. The results indicate that contingent negative variation (CNV) and P300 components changed according to task demands. In the time-related task, amplitudes and duration of both components increased as a function of stimulus duration and easier discriminability.

The effect of age on word-stem cued recall: a behavioral and electrophysiological study.

The present study investigated the effects of aging on behavioral cued-recall performance and on the neural correlates of explicit memory using event-related potentials (ERPs) under shallow and deep encoding conditions. At test, participants were required to complete old and new three-letter word stems using the letters as retrieval cues. The main results were as follows: (1) older participants exhibited the same level of explicit memory as young adults with the same high level of education.

Cortico-striatal representation of time in animals and humans.

Interval timing in the seconds-to-minutes range is crucial to learning, memory, and decision-making. Recent findings argue for the involvement of cortico-striatal circuits that are optimized by the dopaminergic modulation of oscillatory activity and lateral connectivity at the level of cortico-striatal inputs. Striatal medium spiny neurons are proposed to detect the coincident activity of specific beat patterns of cortical oscillations, thereby permitting the discrimination of supra-second durations based upon the reoccurring patterns of subsecond neural firing.

Brain activity during interval timing depends on sensory structure.

Precise timing is crucial for accurate perception and action in the range of hundreds of milliseconds. One still unresolved question concerns the influence of sensory information content on timing mechanisms. Numerous studies have converged to suggest that the CNV (Contingent Negative Variation), a slow negative wave that develops between two events, notably reflects temporal processing of the interval between these two events.

How emotional auditory stimuli modulate time perception.

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.

Role of the medial temporal lobe in time estimation in the range of minutes.

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.

Differential effects of the stimulus sequence on CNV and P300.

During the presentation of stimulus sequences in oddball paradigms, participants tend to implicitly evaluate the conditional probability of target occurrence. It is not sure, however, if subjective estimation of conditional probabilities modulates target expectancy and target processing in the same manner. In the present experiment, the amplitudes of CNV and P300 were studied separately to compare preparatory and decision mechanisms and their sensitivity to variations in target probability.

Age-related changes in duration reproduction: involvement of working memory processes.

The aim of the present research was to study age-related changes in duration reproduction by differentiating the working memory processes underlying this time estimation task. We compared performances of young and elderly adults in a duration reproduction task performed in simple and concurrent task conditions. Participants were also administered working memory tests to measure storage and central executive functions.

Differential involvement of internal clock and working memory in the production and reproduction of duration: a study on older adults.

The present study uses the inter-individual variability in time perception of a group of elderly participants to differentiate the processes underlying time production and time reproduction. Participants performed duration production and reproduction tasks. They were also administered working memory tests and a spontaneous motor tempo task.

The effect of encoding manipulation on word-stem cued recall: an event-related potential study.

The purpose of the present study was to find out whether the neural correlates of explicit retrieval from episodic memory would vary according to conditions at encoding when the words were presented in separate study/test blocks. Event-related potentials (ERPs) were recorded while participants performed a word-stem cued-recall task. Deeply (semantically) studied words were associated with higher levels of recall and faster response times than shallowly (lexically) studied words.

Does priming with awareness reflect explicit contamination? An approach with a response-time measure in word-stem completion.

The present experiment investigates the involvement of awareness in functional dissociations between explicit and implicit tests. In the explicit condition, participants attempted to recall lexically or semantically studied words using word stems. In the implicit condition, they were instructed to complete each stem with the first word which came to mind.

Neural correlates of word-stem priming.

The purpose of this study was to identify the neural correlates of implicit memory in a word-stem completion task. Given that both explicit and implicit retrieval tend to occur in this type of memory task, conventional analyses of old/new event-related potential effects are equivocal. To overcome this problem, depth of processing was manipulated and subjective awareness measured.

Relationship between CNV and timing of an upcoming event.

This study reports an analysis of the Contingent Negative Variation (CNV) recorded on the human scalp during the comparison of a test duration with a previously memorized duration. Results show that CNV activity peaks at the end of the memorized duration, and that its slope varies inversely with the length of this duration. These features of CNV activity are similar to those of climbing neuronal activity observed through intracerebral recordings in animals, and suggest that both activities reflect how the brain encodes the timing of an upcoming event.

Auditory/visual duration bisection in patients with left or right medial-temporal lobe resection.

Patients with unilateral (left or right) medial temporal lobe lesions and normal control (NC) volunteers participated in two experiments, both using a duration bisection procedure. Experiment 1 assessed discrimination of auditory and visual signal durations ranging from 2 to 8 s, in the same test session. Patients and NC participants judged auditory signals as longer than equivalent duration visual signals.

Effects of internal clock and memory disorders on duration reproductions and duration productions in patients with Parkinson's disease.

Patients with Parkinson's disease (PD) exhibit deficits in perceptual and motor timing as well as impairments in memory and attentional processes that are related to dysfunction of dopaminergic systems in the basal ganglia. The aim of the present study was to assess the relationships existing between impaired duration judgments and defective memory and attention in PD patients. We compared time performance of medicated PD patients and control subjects on a duration reproduction task that is highly memory-dependent, and on a duration production task that could reveal effects of changes in the speed of internal time-keeping mechanisms.

Neural network involved in time perception: an fMRI study comparing long and short interval estimation.

In this study, long ( approximately 1,300 ms) and short duration ( approximately 450 ms) estimation trials in an event-related functional MRI (fMRI) study were contrasted in order to reveal the regions within a time estimation network yielding increased activation with the increase of the duration to be estimated. In accordance with numerous imaging studies, our results showed that the presupplementary motor area (preSMA), the anterior cingulate, the prefrontal and parietal cortices, and the basal ganglia were involved in the estimation trials whatever the duration to be estimated. Moreover, only a subset of the regions within this distributed cortical and subcortical network yielded increased activation with increasing time, namely, the preSMA, the anterior cingulate cortex, the right inferior frontal gyrus (homolog to Broca's area), the bilateral premotor cortex, and the right caudate nucleus.

What is common to brain activity evoked by the perception of visual and auditory filled durations? A study with MEG and EEG co-recordings.

EEG and MEG scalp data were simultaneously recorded while human participants were performing a duration discrimination task in visual and auditory modality, separately. Short durations were used ranging from 500 to 900 ms, among which participants had to discriminate a previously memorized 700-ms "standard" duration. Behavioral results show accurate but variable performance within and between participants with expected modality effects: the percentage of responses was greater and the mean response time was shorter for auditory than for visual signals.

Time perception depends on accurate clock mechanisms as well as unimpaired attention and memory processes.

We report a series of studies aimed at characterizing the relationships between duration judgments and slowing down of the internal clock, attention and memory deficits. Different groups of participants (elderly people, patients with Parkinson's disease, patients with severe traumatic brain injury, and patients with temporal lobe lesions) performed a duration reproduction task and a duration production task in two conditions: a control counting condition and a concurrent reading condition. Participants were also administered reaction time tasks, tapping tasks, and a battery of attention and memory tests.

Basal ganglia and supplementary motor area subtend duration perception: an fMRI study.

Brain imaging studies on duration perception usually report the activation of a network that includes the frontal and mesiofrontal cortex (supplementary motor area, SMA), parietal cortex, and subcortical areas (basal ganglia, thalamus, and cerebellum). To address the question of the specific involvement of these structures in temporal processing, we contrasted two visual discrimination tasks in which the relevant stimulus dimension was either its intensity or its duration. Eleven adults had to indicate (by pressing one of two keys) whether they thought the duration or the intensity of a light (LED) was equal to (right hand) or different from (left hand) that of a previously presented standard.

Relationships between time estimation, memory, attention, and processing speed in patients with severe traumatic brain injury.

The present experiment was aimed at investigating the effects of memory and attention deficits and of information processing slowing on time estimation in patients with severe traumatic brain injury (TBI). Patients with TBI and normal control subjects reproduced and produced durations (5, 14, 38s) in both a control counting condition and in a concurrent reading condition. They also performed finger-tapping tasks at a free rate and at a 1s rate.

When time is up: CNV time course differentiates the roles of the hemispheres in the discrimination of short tone durations.

Numerous studies have suggested that the CNV (contingent negative variation), a negative slow wave developing between a warning and an imperative stimulus, reflects, among other things, temporal processing of the interval between these two stimuli. One aim of the present work was to specify the relationship between CNV activity and the perceived duration. A second aim was to establish if this relationship is the same over the left and right hemispheres.