Timing dysfunctions in schizophrenia as measured by a repetitive finger tapping task

Schizophrenia may be associated with a fundamental disturbance in the temporal coordination of information processing in the brain, leading to classic symptoms of schizophrenia such as thought disorder and disorganized and contextually inappropriate behavior. Although a variety of behavioral studies have provided strong evidence for perceptual timing deficits in schizophrenia, no study to date has directly examined overt temporal performance in schizophrenia using a task that differentially engages perceptual and motor-based timing processes. The present study aimed to isolate perceptual and motor-based temporal performance in individuals diagnosed with schizophrenia using a repetitive finger-tapping task that has previously been shown to differentially engage brain regions associated with perceptual and motor-related timing behavior. Thirty-two individuals with schizophrenia and 31 non-psychiatric control participants completed the repetitive finger-tapping task, which required participants to first tap in time with computer-generated tones separated by a fixed intertone interval (tone-paced tapping), after which the tones were discontinued and participants were required to continue tapping at the established pace (self-paced tapping). Participants with schizophrenia displayed significantly faster tapping rates for both tone- and self-paced portions of the task compared to the non-psychiatric group. Individuals diagnosed with schizophrenia also displayed greater tapping variability during both tone- and self-paced portions of the task. The application of a mathematical timing model further indicated that group differences were primarily attributable to increased timing – as opposed to task implementation – difficulties in the schizophrenia group, which is noteworthy given the broad range of impairments typically associated with the disorder. These findings support the contention that schizophrenia is associated with a broad range of timing difficulties, including those associated with time perception as well as time production.     

Effects of interval duration on temporal processing in schizophrenia

INTRODUCTION: Temporal processing has received scant attention in the literature pertaining to cognitive deficits in patients with schizophrenia. Previous research suggests that patients with schizophrenia exhibit temporal perception deficits on both auditory and visual stimuli. The current study investigated the effects of interval manipulation to (1) replicate the original findings with a larger sample and an increased number of trials (2) assess the degree to which both patients and controls can differentiate temporal changes in a range of experimental interstimulus intervals, and (3) explore whether different interstimulus interval durations pose different levels of difficulty for the patients with schizophrenia. METHODS: Participants were asked to decide whether temporal intervals were shorter or longer than standard intervals on a computer-based auditory temporal perception task. The standard interval remained the same duration throughout the various tasks. The interstimulus interval separating the standard and experimental intervals varied in the range of 500, 1000, or 3000 ms. Data are presented for a sample of 16 patients with schizophrenia and 15 controls. RESULTS: Data suggest that patients with schizophrenia exhibit deficits in differentiating interval durations across all paradigms compared to their control-group peers on a range of auditory tasks (p<.001). CONCLUSIONS: These results are consistent with a general temporal deficit in schizophrenia. However, the roles of medication and localization are also addressed.     

Deficits of subliminal self-face processing in schizophrenia

Most studies show that self-processing in schizophrenia is impaired at the supraliminal level. Schizophrenic patients generally lack the ability to prioritize the processing of self-related information, such as their own face. However, some evidence suggests that schizophrenic patients may retain intact subliminal processing abilities even though their conscious experiences are compromised. We conducted the first study exploring schizophrenic patients’ subliminal self-face processing. Using a breaking continuous flash suppression (bCFS) paradigm, we interocularly suppressed face images (self, famous, and unknown faces). Participants’ reaction times to detect the faces when they broke the suppression were recorded as an index for the subliminal processing of faces. Unlike the healthy controls, schizophrenic patients did not demonstrate a processing advantage for their own face when it broke interocular suppression; only a face familiarity effect was found. These findings contribute to the understanding of self-processing deficits in schizophrenia.     

Temporal landmarks: proximity prevails

Subjects in conditioning experiments time their conditioned responses relative to the onsets of the conditioned stimuli (CSs). These onsets are temporal landmarks, by reference to which subjects may estimate the location of the unconditioned stimulus (US) in time. In a serial compound conditioning paradigm, a long duration CS comes on first, followed later by a second shorter CS, creating both a long-range and a short-range predictor of the US. We ask whether displacing the short-range predictor relative to the long-range predictor causes subjects to strike a compromise between the different temporal locations predicted by the two CSs. In three experiments with pigeons, we varied the training conditions so as to favor or militate against this outcome. However, in all conditions, there was no compromise; after the onset of the displaced short-range CS, the timing of conditioned responding was governed by it alone. This result contrasts with the compromises that are seen when the feeding time predicted by a CS is put in conflict with the time predicted by the circadian clock, and with the similar compromises sometimes seen when a nearby spatial landmark is displaced relative to a larger spatial context. Electronic Publication     

Temporal processing capabilities in repetition conduction aphasia

This study investigates the temporal resolution capacities of the central-auditory system in a subject (NP) suffering from repetition conduction aphasia. More specifically, the patient was asked to detect brief gaps between two stretches of broadband noise (gap detection task) and to evaluate the duration of two biphasic (WN-3) continuous noise elements, starting with white noise (WN) followed by 3 kHz bandpass-filtered noise (duration discrimination task). During the gap detection task, the two portions of each stimulus were either identical (“intra-channel condition”) or differed (“inter-channel condition”) in the spectral characteristics of the leading and trailing acoustic segments. NP did not exhibit any deficits in the intra-channel condition of the gap detection task, indicating intact auditory temporal resolution across intervals of 1–3 ms. By contrast, the inter-channel condition yielded increased threshold values. Based upon the “multiple-looks” model of central-auditory processing, this profile points at a defective integration window operating across a few tens of milliseconds – a temporal range associated with critical features of the acoustic speech signal such as voice onset time and formant transitions. Additionally, NP was found impaired during a duration discrimination task addressing longer integration windows (ca. 150 ms). Concerning speech, this latter time domain approximately corresponds to the duration of stationary segmental units such as fricatives and long vowels. On the basis of our results we suggest, that the patient’s auditory timing deficits in non-speech tasks may account, at least partially, for his impairments in speech processing.     

Effortful versus automatic emotional processing in schizophrenia: Insights from a face-vignette task

Adaptive emotional responding relies on dual automatic and effortful processing streams. Dual-stream models of schizophrenia (SCZ) posit a selective deficit in neural circuits that govern goal-directed, effortful processes versus reactive, automatic processes. This imbalance suggests that when patients are confronted with competing automatic and effortful emotional response cues, they will exhibit diminished effortful responding and intact, possibly elevated, automatic responding compared to controls. This prediction was evaluated using a modified version of the face-vignette task (FVT). Participants viewed emotional faces (automatic response cue) paired with vignettes (effortful response cue) that signalled a different emotion category and were instructed to discriminate the manifest emotion. Patients made less vignette and more face responses than controls. However, the relationship between group and FVT responding was moderated by IQ and reading comprehension ability. These results replicate and extend previous research and provide tentative support for abnormal conflict resolution between automatic and effortful emotional processing predicted by dual-stream models of SCZ.     

Sound improves diminished visual temporal sensitivity in schizophrenia

Visual temporal processing and multisensory integration (MSI) of sound and vision were examined in individuals with schizophrenia using a visual temporal order judgment (TOJ) task. Compared to a non-psychiatric control group, persons with schizophrenia were less sensitive judging the temporal order of two successively presented visual stimuli. However, their sensitivity to visual temporal order improved as in the control group when two accessory sounds were added (temporal ventriloquism). These findings indicate that individuals with schizophrenia have diminished sensitivity to visual temporal order, but no deficits in the integration of low-level auditory and visual information.     

Temporal generalization gradients following an interdimensional discrimination protocol

We investigated the effects of interdimensional discrimination training in the temporal generalization gradient. In a matching-to-sample task, pigeons learned to choose key S after a T–s houselight sample and key NS in the absence of the houselight sample. For one group of pigeons, T?=?20?s; for another, T?=?10?s. Subsequently, houselight duration was varied to obtain temporal generalization gradients. Results showed that (a) proportion S increased as houselight duration ranged from 0?s to T?s and then remained high for houselight durations longer than T; (b) the gradients were well described by negative-exponential functions; (c) these non-flat gradients were present from the beginning of testing, and; (d) the average gradients obtained with T?=?20?s and T?=?10?s overlapped when plotted in relative time. We conclude that temporal control does not require explicit discrimination training along the temporal dimension, and that temporal generalization gradients obtained with an interdimensional protocol show the scalar property of timing. We discuss how these findings challenge current models of timing.     

Memory in schizophrenia and affective disorders*

The purpose of the present study was to investigate the stability of memory and information processing in schizophrenics and affectively disturbed patients. Twenty-two schizophrenics, eight affectives and 14 normal controls were tested twice, with an interval of approximately one year. Results showed that normals performed better than schizophrenics and affectively disturbed patients on almost all of the cognitive measures. The differences reached a level of significance on a reaction time test, a vigilance task and a long-term memory task. The only measure where the difference did not reach a level of significance was on a short-term memory test. Groups' performance to some extent changed over time on most of the measures, but the changes were not significantly different for different groups.     

Temporal parameters as cues to phrasal boundaries: a comparison of processing by left- and right-hemisphere brain-damaged individuals

Two experiments were conducted to examine the ability of left- (LHD) and right-hemisphere-damaged (RHD) patients and normal controls to use temporal cues in rendering phrase grouping decisions. The phrase "pink and black and green" was manipulated to signal a boundary after "pink" or after "black" by altering pre-boundary word durations and pause durations at the boundary in a stepwise fashion. Stimuli were presented to listeners auditorily along with a card with three alternative groupings of colored squares from which to select the presented alternative. Results revealed that normal controls were able to use both temporal cues to identify the intended grouping. In contrast, LHD patients required longer than normal pause durations to consistently identify the intended grouping, suggesting a higher than normal threshold for perception of temporal prosodic cues. Surprisingly, the RHD patients exhibited great difficulty with the task, perhaps due to the limited acoustic cues available in the stimuli.     

Hemispheric processing of idioms in schizophrenia and autism spectrum disorder

Studies conducted on individuals with schizophrenia (SZ) and autism spectrum disorder (ASD) show that they find it difficult to comprehend figurative language, and have a tendency to interpret it literally. This study examines hemispheric processing of idioms in patients with SZ, in comparison to individuals with ASD. Seventeen adults with SZ and 18 adults with ASD participated in the study. The two clinical groups were matched in age, vocabulary scores and verbal executive function scores. Using the divided visual field paradigm, the participants performed a lexical decision task for a target word related to either a literal or a figurative interpretation of an idiom. Whereas SZ patients showed the typical right lateralisation for non-salient literal interpretations of idioms, adults with ASD showed atypical bilateral processing. These findings indicate different hemispheric lateralisation in idiom processing in the two clinical groups.     

Temporal coordination between performing musicians

Many common behaviours require people to coordinate the timing of their actions with the timing of others' actions. We examined whether representations of musicians' actions are activated in coperformers with whom they must coordinate their actions in time and whether coperformers simulate each other's actions using their own motor systems during temporal coordination. Pianists performed right-hand melodies along with simple or complex left-hand accompaniments produced by themselves or by another pianist. Individual performers' preferred performance rates were measured in solo performance of the right-hand melody. The complexity of the left-hand accompaniment influenced the temporal grouping structure of the right-hand melody in the same way when it was performed by the self or by the duet partner, providing some support for the action corepresentation hypothesis. In contrast, accompaniment complexity had little influence on temporal coordination measures (asynchronies and cross-correlations between parts). Temporal coordination measures were influenced by a priori similarities between partners' preferred rates; partners who had similar preferred rates in solo performance were better synchronized and showed mutual adaptation to each other's timing during duet performances. These findings extend previous findings of action corepresentation and action simulation to a task that requires precise temporal coordination of independent yet simultaneous actions.     

Masked and unmasked priming in schizophrenia

Dehaene et al. (2003) showed an absence of conscious, but not masked, conflict effects when patients with schizophrenia performed a number-categorisation priming task. We aimed to replicate these influential results using a different word-categorisation priming task. Counter to Dehaene et al.’s findings, 21 patients and 20 healthy controls showed similar congruence effects for both masked and visible primes. Within patients, a reduced congruence effect for visible primes associated with longer duration of illness and more severe behavioural disorganisation. Patients, unlike controls, were no slower to respond to targets that followed visible compared to masked primes. Conscious conflict effects on priming tasks are not universally reduced in schizophrenia but may associate with chronicity and behavioural disorganisation. That patients were no slower when the preceding primes were clearly visible accords with evidence elsewhere that information processing in schizophrenia is driven more by immediate conscious experience and constrained less by prior events.     

Temporal integration of face view sequences and recognition of novel views

When faces are learned from rotating view sequences, novel views may be recognized by matching them with an integrated representation of the sequence or with individual views. An integrated-representation process should benefit from short view durations, and thus from the inclusion of views in a short temporal window, allowing the distribution of attention over the entire sequence. A view-matching process should benefit from long view durations, allowing the attention to focus on each view. In a sequential comparison task, we tested the recognition of learned and novel interpolated and extrapolated views after learning faces from rapid and slow sequences (240 ms or 960 ms for each view). We found a superiority of rapid over slow sequences, in favour of the integrated-representation hypothesis. In addition, the recognition pattern for the different viewpoints in the sequence depended on the absence or presence of extrapolated views, showing a bias of the distribution of attention.     

Disturbances of spontaneous empathic processing relate with the severity of the negative symptoms in patients with schizophrenia: A behavioural pilot-study using virtual reality technology

Behavioural and neuroimaging data have recently pointed out that empathy (feeling into someone else) is associated with mental imagery and transformation related to one’s and other’s visuo-spatial perspectives. Impairments of both empathic and visuo-spatial abilities have been observed in patients with schizophrenia. Especially, it has been suggested that schizophrenics are altered in spontaneously simulating another individual’s first-person experience. However, there is so far only little evidence regarding the relationship between deficits in empathy and disturbances in spontaneous heterocentered coding in schizophrenia. In the present pilot-study, we tested with schizophrenic patients our behavioural paradigm that enables to measure from the bodily postures and movements whether individuals in ecologically more valid conditions are interacting with another individual by using egocentered – as in sympathy (feeling with someone else) – or heterocentered – as in empathy – visuo-spatial mechanisms. For that, ten patients and ten controls, standing and moving, interacted with a virtual tightrope walker, displayed life-sized, standing and moving as well. We show that patients with higher negative symptoms had, in most cases, deficits in spontaneously using heterocentered visuo-spatial mechanisms and employed preferentially an egocentered referencing to interact with the avatar. In contrast, preserved spontaneous heterocentered visuo-spatial strategies were not linked to a prevailing negative or positive symptomatology. Our data suggest that the severity of the negative symptoms in schizophrenia relates with disturbances of spontaneous (“on-line”) empathic processing in association with lower scoring self-reported trait cognitive empathy.     

Effects of Age on the Temporal Organization of Working Memory in Deaf Signers

ABSTRACT

Deaf native signers have a general working memory (WM) capacity similar to that of hearing non-signers but are less sensitive to the temporal order of stored items at retrieval. General WM capacity declines with age, but little is known of how cognitive aging affects WM function in deaf signers. We investigated WM function in elderly deaf signers (EDS) and an age-matched comparison group of hearing non-signers (EHN) using a paradigm designed to highlight differences in temporal and spatial processing of item and order information. EDS performed worse than EHN on both item and order recognition using a temporal style of presentation. Reanalysis together with earlier data showed that with the temporal style of presentation, order recognition performance for EDS was also lower than for young adult deaf signers. Older participants responded more slowly than younger participants. These findings suggest that apart from age-related slowing irrespective of sensory and language status, there is an age-related difference specific to deaf signers in the ability to retain order information in WM when temporal processing demands are high. This may be due to neural reorganisation arising from sign language use. Concurrent spatial information with the Mixed style of presentation resulted in enhanced order processing for all groups, suggesting that concurrent temporal and spatial cues may enhance learning for both deaf and hearing groups. These findings support and extend the WM model for Ease of Language Understanding.     

时间分层加工研究述评

为了探讨数秒内不同层级时间加工的特性,研究者分别从“时间信息加工”和“信息加工的计时特性”角度开展了一系列研究。Münsterberg (1889)、Michon(1985) 、Lewis 和 Miall(2003) 及Vierodt(1868)从前一角度,分别指出1/3秒、1/2秒、1秒及3秒可能是数秒以内时距加工机制的分界点,分界点以下与以上的加工机制存在差异。P?ppel(1997, 2009)则从后一角度指出限制信息加工过程的两类时间窗,一类时间窗是以20-60毫秒振荡周期运行的高频系统,属于初级整合单元;另一类时间窗主要是处理2-3秒以内事件系列的低频系统,属于高级整合单元。前一类时间窗可以为信息加工整合基本的心理事件,后一类时间窗则是把2-3秒内的心理事件整合为基本知觉单元。基于以往研究的剖析,我们认为1/3秒、1/2秒及1秒等分界点的真伪性尚需进一步验证,并进一步假设40毫秒以内时间不能觉察为时距;40毫秒至3秒之间,随着长度增加,自动化加工减弱,控制性加工增强;3秒以上主要为控制性加工,涉及记忆过程。     

The effect of Parkinson's disease on time estimation as a function of stimulus duration range and modality

The present research sought to investigate the role of the basal ganglia in timing of sub- and supra-second intervals via an examination of the ability of people with Parkinson's disease (PD) to make temporal judgments in two ranges, 100-500 ms, and 1-5 s. Eighteen non-demented medicated patients with PD were compared with 14 matched controls on a duration-bisection task in which participants were required to discriminate auditory and visual signal durations within each time range. Results showed that patients with PD exhibited more variable duration judgments across both signal modality and duration range than controls, although closer analyses confirmed a timing deficit in the longer duration range only. The findings presented here suggest the bisection procedure may be a useful tool in identifying timing impairments in PD and, more generally, 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.     

Temporal preparation and inhibitory deficit in fibromyalgia syndrome

Cognitive deficits in fibromyalgia may be specifically related to controlled processes, such as those measured by working memory or executive function tasks. This hypothesis was tested here by measuring controlled temporal preparation (temporal orienting) during a response inhibition (go no-go) task. Temporal orienting effects (faster reaction times for targets appearing at temporally attended vs. unattended moments) and response inhibition were impaired in fibromyalgia compared to the control group. It is concluded that frontal networks underlying attentional control (temporal orienting and response inhibition) can be a dysfunctional neurocognitive mechanism in fibromyalgia.     

A mechanism of timing variability underlying the association between the mean and SD of asynchrony

Sensorimotor timing behaviors typically exhibit an elusive phenomenon known as the negative asynchrony. When synchronizing movements (e.g. finger taps) with an external sequence (e.g. a metronome), people’s taps precede event onsets by a few tens of milliseconds. We recently reported that asynchrony is less negative in participants with lower asynchrony variability. This indicates an association between negative asynchrony and variability of timing. Here, in 24 metronome-synchronization data sets, we modeled asynchrony series using a sensorimotor synchronization model that accounts for serial dependence of asynchronies. The results showed that the modeling well captured the negative correlation between the mean and SD of asynchrony. The finding suggests that serial dependence in asynchronies is an essential mechanism of timing variability underlying the association between the mean and SD of asynchrony.