Phase correction, phase resetting, and phase shifts after subliminal timing perturbations in sensorimotor synchronization.

Recent studies of synchronized finger tapping have shown that perceptually subliminal phase shifts in an auditory sequence are rapidly compensated for in the motor activity (B. H. Repp, 2000a). Experiment 1 used a continuation-tapping task to confirm that this compensation is indeed a phase correction, not an adjustment of the central timekeeper period. Experiments 2–5 revealed that this phase correction occurs even when there is no ordinary sensorimotor asynchrony-when the finger taps are in antiphase or arbitrary phase relative to the auditory sequence (Experiments 2 and 3) or when the tap coinciding with the sequence phase shift is withheld (Experiments 4 and 5). The phase correction observed in the latter conditions was instantaneous, which suggests that phase resetting occurs when the motor activity is discontinuous. A prolonged phase shift suggestive of overcompensation was observed in some conditions, which poses a challenge to pure phase correction models. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Prefrontal involvement in "temporal bridging" and timing movement

Brain activity exclusively related to a temporal delay has rarely been investigated using modern brain imaging. In this study we exploited the temporal resolution of functional magnetic resonance imaging (fMRI) to characterise, by sinusoidal regression analysis, differential neuroactivation patterns induced in healthy subjects by two sensorimotor synchronization tasks different in their premovement delay of either 0.6 s or 5 s. The short event rate condition required rhythmic tapping, while the long event rate condition required timing of intermittent movements. Left rostral prefrontal cortex, medial frontal cortex, SMA and supramarginal gyrus demonstrated increased MR signal intensity during low frequency synchronization, suggesting that these brain regions form a distributed neural network for cognitive time management processes, such as time estimation and motor output timing. Medial frontal cortex showed a biphasic pattern of response during both synchronization conditions, presumably reflecting frequency-independent motor output related attention. As predicted, sensorimotor and visual association areas demonstrated increased MR signal intensity during high frequency synchronization.     

Temporal processing in the basal ganglia.

This study investigated the role of the basal ganglia in timing operations. Nondemented, medicated Parkinson's disease (PD) patients and controls were tested on 2 motor-timing tasks (paced finger tapping at a 300- or 600-ms target interval), 2 time perception tasks (duration perception wherein the interval between the standard tone pair was 300 or 600 ms), and 2 tasks that controlled for the auditory processing (frequency perception) demands of the time perception task and the movement rate (rapid tapping) in the motor-timing task. Using A. M. Wing and A. B. Kristofferson's (1973) model, the total variability in motor timing was partitioned into a clock component, which reflects central timekeeping operations, and a motor delay component, which estimates random variability due to response implementation processes. The PD group was impaired at both target intervals of the time perception and motor-timing tasks. Impaired motor timing was due to elevated clock but not motor delay variability. The findings implicate the basal ganglia and its thalamocortical connections in timing operations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Timing and trajectory in rhythm production.

The Wing-Kristofferson movement timing model (A. M. Wing & A. B. Kristofferson, 1973a, 1973b) distinguishes central timer and motor implementation processes. Previous studies have shown that increases in interresponse interval (IRI) variability with mean IRI are due to central timer processes, not motor implementation. The authors examine whether this is true with IRI duration changes in binary rhythm production. Ten participants provided IRI and movement data in bimanual synchronous tapping under equal (isochronous) and alternating (rhythm) interval conditions. Movement trajectory changes were observed with IRI duration (300, 500, or 833 ms) and for 500-ms IRIs produced in rhythm contexts (300/500 ms, 500/833 ms). However, application of the Wing-Kristofferson model showed that duration and context effects on IRI variability were attributable largely to timer processes with relatively little effect on motor processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The time of our lives: Life span development of timing and event tracking.

Life span developmental profiles were constructed for 305 participants (ages 4-95) for a battery of paced and unpaced perceptual-motor timing tasks that included synchronize-continue tapping at a wide range of target event rates. Two life span hypotheses, derived from an entrainment theory of timing and event tracking, were tested. A preferred period hypothesis predicted a monotonic slowing of a preferred rate (tempo) of event tracking across the life span. An entrainment region hypothesis predicted a quadratic profile in the range of event rates that produced effective timing across the life span; specifically, age-specific entrainment regions should be narrower in childhood and late adulthood than in midlife. Findings across tasks provide converging support for both hypotheses. Implications of these findings are discussed for understanding critical periods in development and age-related slowing of event timing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The referential dynamics of cognition and action.

Referential behavior theory (RBT), a general dynamical approach to psychological and related systems that operate through a control or referencing process, is introduced. A review of existing evidence shows that this approach can apply to a variety of human and animal systems and tasks, whether the framing language is that of homeostasis, error correction, coupled biological oscillators, motor control, adaptive change, cognitive goal-setting, evaluation and refinement, or neural network learning. Thus, RBT provides a path for reconciliation of dynamical and information-processing accounts of action and cognition. RBT generates a class of mathematical equations, one of which, the discrete control equation (DCE), forms the basis for more detailed investigation. The primary focus here is on the application of the DCE to the temporal structure of regular human movement. Given certain conditions, the equation produces various standard (and new, more general) forms of the circle map class that governs relative phase in motor coordination and, hence, generates well-documented nonlinear "dynamical" motor phenomena such as behavioral attractors, phase transitions, critical slowing, and so on. Under certain other conditions, the DCE produces the linear stochastic timing models… (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Motor disruption in the production of time intervals with finger taps.

Two experiments with 19 adults examined the variance associated with the motor component in a time production task involving a series of finger taps. Use of the segmentation strategy described by S. Grondin (1992) allowed the isolation of a part of the variance associated with the motor component in such a tapping task. Replacing a finger tap by an internal indicator reduced the coefficient of variation by about .5% per sec. Results show that the choice of subintervals, when an interval is segmented during a timing task, is a major source of variance. The segmentation strategy provides a general framework for analyzing the part of the variability provoked by each of 2 components (the clock and the motor system) involved in a time interval production task. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The costs of taking it slowly: Fast and slow movement timing in older age.

We investigated adult age-differences in timing control of fast vs. slow repetitive movements using a dual-task approach. Twenty-two young (M = 24.23 yr) and 22 older adults (M = 66.64 yr) performed three cognitive tasks differing in working memory load and response production demands and they tapped series of 550-ms or 2100-ms target intervals. Single-task timing was comparable in both groups. Dual-task timing was characterized by shortening of produced intervals and increases in drift and variability. Dual-task costs for both cognitive and timing performances were pronounced at slower tapping tempos, an effect exacerbated in older adults. Our findings implicate attention and working memory processes as critical components of slow movement timing and sources of specific challenges thereof for older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Automaticity and voluntary control of phase correction following event onset shifts in sensorimotor synchronization.

Seven experiments show that an event onset shift (EOS) in an auditory sequence causes an involuntary phase correction response (PCR) in synchronized finger tapping. This PCR is (a) equally large in inphase and antiphase tapping; (b) reduced but still present when the EOS occurs in either of two interleaved (target- distractor) sequences; (c) unaffected by increased pitch separation between these sequences; (d) asymptotic in magnitude as EOS magnitude increases, unlike the intentional PCR to expected phase shifts; and (e) enhanced when the EOS precedes the onset of tapping, because of phase resetting. Thus, phase correction is revealed to be partially automatic and partially under voluntary control, and to be based mainly on temporal information derived from simple onset detection. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Deficient motor synchrony in schizophrenia.

Introduced a laboratory measure of motor function, synchronization of tapping with an auditory stimulus, as an index of motor disorganization in schizophrenia. It was hypothesized that (a) schizophrenics' performance on this task would be distinguishable from that of controls and would reflect a relative inability to take advantage of stimulus predictability, independent of task difficulty; (b) clinical measures of disturbed motor behavior would be associated with poorer synchronization; and (c) synchronization performance would be associated with clinical ratings of formal thought disorder and type-token ratio assessment of disorganization in spoken language. 16 schizophrenic, 8 affective, and 8 normal controls (18–48 yrs) were studied. The schizophrenics showed a specific pattern of disrupted synchrony not consistent with explanations based on S motivation, task difficulty, motor dexterity, a general psychosis factor, drug effects, or tapping speed ability. Deficient motor performance was associated with clinical evidence of abnormal movement and disturbed thinking and with the type-token ratio. (44 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A model of synchronization of motor acts to a stimulus sequence. II. Stability analysis, error estimation and simulations

In Part I (Mates 1994), a linear model of timing and error-corrections was constructed that aims at an explanation of the mechanisms underlying a subject's performance in an experimental paradigm, in which the task is to synchronize a sequence of motor acts to a sequence of stimuli. The model consists of two error-corrective mechanisms: (1) corrections of period (inverted frequency) of the sequence of responses; (2) corrections of phase shift of that sequence (synchronization error). In this paper, the influence of the physiologically justifiable model variables and of initial conditions on the steady-state response sequence as well as the stability of performance of the model are analyzed. The model is stable for error-correction gains in the range from 0 to 2. Comparison with known empirical data supports the assumption that reasonable values are less than 1. Furthermore, an alternative to the basic linear model is introduced in which the possible character of the process of subjective acquisition of the synchronization error is discussed. On the basis of findings from other experimental paradigms (fusion and order threshold) it can be assumed that the subjective estimate is a nonlinear function of the difference between the temporal central availability of internal representations of the stimulus and response-feedback events. Some other known synchronization data are simulated by the nonlinear modification of the model in this paper. A good fit of the simulation results achieved further justifies the model structure proposed. Finally, the possible effect of the subjective synchronization-error estimation on empirical data is discussed.     

Timing processes are correlated when tasks share a salient event.

Event timing is manifested when participants make discrete movements such as repeatedly tapping a key. Emergent timing is manifested when participants make continuous movements such as repeatedly drawing a circle. Here we pursued the possibility that providing salient perceptual events to mark the completion of time intervals could allow circle drawing and tapping to share a common timing process. Individual differences in timing performance were correlated in the tapping and circle drawing tasks when a salient auditory event marked the completion of a cycle. The results suggest that the distinction between event timing and emergent timing does not inhere solely in kinematics but inheres as well in the way task goals are represented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Order effects on the Halstead-Reitan Neuropsychological Test Battery and allied procedures.

Four different orders of the Halstead-Reitan Neuropsychological Test Battery and the WAIS were administered to 167 adults who had a variety of suspected or confirmed neurological disorders. Of the 17 measures utilized, only tapping with the dominant hand showed evidence of being affected by the order in which the task was administered. Data suggest that a more accurate assessment of motor abilities may be obtained by presenting the tapping task early in a testing session. The differences observed on the tapping task did not result in a significant difference in the number of Ss in each order group whose Halstead Impairment Index score was in the impaired range, which indicates that the difference would be unlikely to lead to errors in clinical judgment in regard to an assessment of an overall neuropsychological status. Results indicate that order of task presentation had little effect on performance in either impaired or unimpaired clinical populations. (8 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Relationships among age, conditioned stimulus–unconditioned stimulus interval, and neuropsychological test performance.

To evaluate the effect of age at various conditioned stimulus (CS)–unconditioned stimulus (US) intervals, 144 young, middle-aged, and older adults were tested on eyeblink classical conditioning at CS–US intervals of 500, 1,000, or 1,500 ms. Reaction time, response timing, motor learning, declarative memory, and attention were assessed to identify correlates of conditioning at various CS–US intervals. Previously reported middle-aged and older adults were impaired at a 400-ms CS–US interval, but the addition of 100 ms to the CS–US interval in this study enabled equal conditioning in middle-aged and young adults. At a 1,000-ms CS–US interval, older adults remained significantly impaired. It was only at the 1,500-ms CS–US interval that conditioning was equal for the 3 age groups. Measures of reaction time, timing, and motor learning were not correlated systematically with conditioning. Whereas the results of age differences at various CS–US intervals were clear and striking, patterns of relationships among neuropsychological and conditioning variables were not consistent in indicating sources of age differences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age-specific problems in rhythmic timing.

The authors investigated performance in 2 rhythm tasks in young (M?=?23.8 years) and older (M?=?71.4 years) amateur pianists to test whether slowing of a central clock can explain age-related changes in timing variability. Successive keystrokes in the rhythm tasks were separated by either identical (isochronous) time intervals or varying (anisochronous) intervals. Variability was comparable for young and older adults in the isochronous task; pronounced age effects were found for the anisochronous rhythm. Analyses of covariances between intervals rule out slowing of a central clock as an explanation of the findings, which instead support the distinction between target specification, timekeeper execution, and motor implementation proposed by the rhythm program hypothesis (D. Vorberg & A. M. Wing, 1996). Age stability was found at the level of motor implementation, but there were age-related deficits for processes related to target-duration specification. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Slowness and age: Speed-accuracy mechanisms.

Young and older adults' mechanisms of trial-by-trial control of accuracy and choice reaction times (RTs) were compared in 2,000 trials. With equal mean error rates, the older group's correct and error RT were longer, and their within-subject distribution was a linear function of the younger group's. Conditional accuracy functions (CAFs) were very similar in location and shape, with both groups achieving 95% accuracy at the same RT. Combining RT distributions with CAFs showed that the older group did not track their limits as often as the younger group, and they were more careful, having fewer very fast (near random) responses, more average speed responses in long error-free runs, and more slowing following an error. All participants were faster before an error and slower immediately after, but the older participants had coarser RT control. To compensate for this, the older participants produced slower responding to avoid the very fast, high-error part of the CAF. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Variability in isochronous tapping: Higher order dependencies as a function of intertap interval.

Isochronous serial interval production (ISIP) data, as from unpaced finger tapping, exhibit higher order dependencies (drift). This fact has largely been ignored by the timing literature, one reason probably being that influential timing models assume random variability. Men and women, 22–36 years old, performed a synchronization–continuation task with intertap intervals (ITI) from 0.4 s to 2.2 s. ISIP variability was partitioned into components attributable to drift and 1st-order serial correlation, and the results indicate that (a) drift contributes substantially to the dispersion for longer ITIs, (b) drift and 1st-order correlation are different functions of the ITI, and (c) drift exhibits break close to 1.0 s and 1.4 s ITI. These breaks correspond to qualitative changes in performance for other temporal tasks, which suggests common timing processes across modalities and tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Component analysis of a rhythmic finger tapping task in individuals with senile dementia of the Alzheimer type and in individuals with Parkinson's disease.

The present experiment examined different components of motor control that may be impaired in normal aging, senile dementia of the Alzheimer type (SDAT), and Parkinson's disease (PD). Specifically, A. M. Wing and A. B. Kristofferson's (1973) formal quantitative model of rhythmic finger tapping was used to obtain estimates of central timekeeping and response execution components of timing control. Ss included young college students, healthy older adults, nondemented individuals with PD. and individuals with very mild and mild SDAT. Individuals with mild SDAT exhibited a breakdown in the central timekeeping mechanism but not in the execution of the response. Both very mild SDAT and PD individuals did not show any deficits in the 2 timing mechanisms relative to age-matched healthy controls. Finally, there was no effect of normal aging on timing control in this task. This study underscores the importance of examining issues of motor control in SDAT as a function of separate processing components and stages of disease progression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Rhythms and responses.

[Correction Notice: An erratum for this article was reported in Vol 11(5) of Journal of Experimental Psychology: Human Perception and Performance (see record 2008-10975-001). There is a typographical error on page 153. A correction to this error has been provided in the erratum.] Tested the assumption that there is a central clock coordinating behavior in all sensory modalities and response modes. A rhythmic tapping task was used in 3 experiments in which 12 undergraduates first attempted to synchronize responses with brief auditory, tactile, or visual stimuli and then continued to tap at the same rate on their own. Performance was most variable with visual stimuli and least variable with auditory stimuli. Results suggest that performances were not based on a common clock and that different strategies were employed when the task was presented in different modalities. The hypothesis of a single timing mechanism controlling behavior is rejected, and the validity is questioned of information processing models that are formulated without regard to temporal relations among their conjectured processes. Discussion focuses on the relation between successive responses and the means by which timing is accomplished. (56 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Psychomotility in the functional psychoses.

103 hospitalized schizophrenic, schizoaffective, manic-depressive, and non-psychotic psychiatric patients were tested on 5 psychomotility measures: simple RT, traverse RT, tapping speed, dexterity, and strength of grip. Results show generalized slowing among patient groups on simple RT, traverse RT, tapping speed, and manual dexterity. Together with previous research, findings suggest that schizophrenic or affective psychosis implicates processes controlled in the CNS. These processes may reflect a more or less enduring condition of inadequate integration at the neural level that disrupts reality attunement of attention and motor behavior. (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)