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Motor Task (motor + task)

Distribution by Scientific Domains

Medical Sciences	60%
Life Sciences	27%
Psychology	8%
2 Other Domains	5%

Distribution within Medical Sciences

Neurology	61%
Occupational Therapy	6%
7 Other Subdomains	27%

Kinds of Motor Task

simple motor task

Selected Abstracts

Recruitment of Additional Brain Regions to Accomplish Simple Motor Tasks in Chronic Alcohol-Dependent Patients

ALCOHOLISM, Issue 6 2010
Mitchell H. Parks
Background:, Chronic alcohol-dependent patients (ALC) exhibit neurocognitive impairments attributed to alcohol-induced fronto-cerebellar damage. Deficits are typically found in complex task performance, whereas simple tasks may not be significantly compromised, perhaps because of little understood compensatory changes. Methods:, We compared finger tapping with either hand at externally paced (EP) or maximal self-paced (SP) rates and concomitant brain activation in ten pairs of right-hand dominant, age-, and gender-matched, severe, uncomplicated ALC and normal controls (NC) using functional magnetic resonance imaging (fMRI). Results:, Mean tapping rates were not significantly different in ALC and NC for either task, but SP tapping variances were greater in ALC for both hands. SP tapping was more rapid with dominant hand (DH) than non-dominant hand (NDH) for both groups. EP and SP tapping with the non-dominant hand demonstrated significantly more activation in ALC than NC in the pre and postcentral gyri, inferior frontal gyrus, inferior parietal lobule, and the middle temporal gyrus. Areas activated only by ALC (not at all by NC) during NDH tapping included the inferior frontal gyrus, middle temporal gyrus, and postcentral gyrus. There were no significant group activation differences with DH tapping. No brain regions activated more in NC than ALC. SP tapping in contrast to EP activated fronto-cerebellar networks in NC, including postcentral gyrus, anterior cingulate, and the anterior lobe and vermis of the cerebellum, but only parietal precuneus in ALC. Conclusions:, These findings with NDH finger tapping support previous reports of neurocognitive inefficiencies in ALC. Inferior frontal activation with EP in ALC, but not in NC, suggests engagement of regions needed for planning, organization, and impulse regulation; greater contralateral parietal lobe activation with SP in ALC may reflect right hemispheric impairments in visuospatial performance. Contrasting brain activation during SP and EP suggests that ALC may not have enlisted a fronto-cerebellar network as did NC but rather employed a higher order planning mode by recruiting parietal lobe functions to attain normal mean finger tapping rates. Elucidation of the compensatory neural mechanisms that allow near normal performance by ALC on simple tasks can inform functional rehabilitation of patients in recovery. [source]

Activity-based restorative therapies: Concepts and applications in spinal cord injury-related neurorehabilitation

DEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 2 2009
Cristina L. Sadowsky
Abstract Physical rehabilitation following spinal cord injury-related paralysis has traditionally focused on teaching compensatory techniques, thus enabling the individual to achieve day-to-day function despite significant neurological deficits. But the concept of an irreparable central nervous system (CNS) is slowly being replaced with evidence related to CNS plasticity, repair, and regeneration, all related to persistently maintaining appropriate levels of neurological activity both below and above the area where the damage occurred. It is now possible to envision functional repair of the nervous system by implementing rehabilitative interventions. Making the transition from "bench to bedside" requires careful analysis of existing basic science evidence, strategic focus of clinical research, and pragmatic implementation of new therapeutic tools. Activity, defined as both function specific motor task and exercise appears to be a necessity for optimization of functional, metabolic, and neurological status in chronic paralysis. Crafting a comprehensive rehabilitative intervention focused on functional improvement through neurological gains seems logical. The terms activity-based restorative therapies, activity-based therapies, and activity-based rehabilitation have been coined in the last 10 years to describe a new fundamental approach to deficits induced by neurological paralysis. The goal of this approach is to achieve activation of the neurological levels located both above and below the injury level using rehabilitation therapies. This article reviews basic and clinical science evidence pertaining to implementation of physical activity and exercise as a therapeutic tool in the management of chronic spinal cord-related neurological paralysis. © 2009 Wiley-Liss, Inc. Dev Disabil Res Rev 2009;15:112,116. [source]

Modulation of spinal inhibitory reflex responses to cutaneous nociceptive stimuli during upper limb movement

EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 3 2008
Romildo Don
Abstract In the present study we investigated the probability, latency and duration of the inhibitory component of the withdrawal reflex elicited by painful electrical stimulation of the index finger in humans. The stimulus consisted of a train of high-intensity pulses. The investigation was carried out in several upper limb muscles during isometric contractions of different strengths and during a motor sequence consisting of reaching, picking up and transporting an object. We used a new algorithm to detect and characterize the inhibitory reflex. The reflex was found in all muscles except the brachioradialis at all the isometric contraction strengths, and showed a distal-to-proximal gradient of latency and duration. Conversely, during movement the reflex probability was high (> 80%) in the anterior deltoid and triceps muscles during reaching, in the extensor carpi radialis muscle during transporting of the object, and in the first interosseous muscle during both picking up and transporting of the object. This modulation of inhibitory reflex transmission in the upper limb muscles suggests that the motor response is organized in such a way as to inhibit the overall ongoing motor task by interrupting motion during reaching and by releasing the object during transporting. This pattern of modulation appears to differ markedly from that previously reported for the excitatory component of the withdrawal reflex. Study of the nociceptive inhibitory reflexes during movement offers new and more profound insights into the functional anatomical organization of the spinal interneuronal network mediating sensory,motor integration. [source]

The essential role of Broca's area in imitation

EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 5 2003
Marc Heiser
Abstract The posterior sector of Broca's area (Brodmann area 44), a brain region critical for language, may have evolved from neurons active during observation and execution of manual movements. Imaging studies showing increased Broca's activity during execution, imagination, imitation and observation of hand movements support this hypothesis. Increased Broca's activity in motor task, however, may simply be due to inner speech. To test whether Broca's area is essential to imitation, we used repetitive transcranial magnetic stimulation (rTMS), which is known to transiently disrupt functions in stimulated areas. Subjects imitated finger key presses (imitation) or executed finger key presses in response to spatial cues (control task). While performing the tasks, subjects received rTMS over the left and right pars opercularis of the inferior frontal gyrus (where Brodmann area 44 is probabilistically located) and over the occipital cortex. There was significant impairment in imitation, but not in the control task, during rTMS over left and right pars opercularis compared to rTMS over the occipital cortex. This suggests that Broca's area is a premotor region essential to finger movement imitation. [source]

Increased cerebral activity in Parkinson's disease patients carrying the DRD2 TaqIA A1 allele during a demanding motor task: a compensatory mechanism?

GENES, BRAIN AND BEHAVIOR, Issue 6 2007
D. Bartrés-Faz
Previous studies suggest that neuroimaging techniques are useful for detecting the effects of functional genetic polymorphisms on brain function in healthy subjects or in patients presenting with psychiatric or neurodegenerative conditions. Former evidence showed that individuals carrying risk alleles displayed broader patterns of brain activity during behavioural and cognitive tasks, despite being clinically comparable to non-carriers. This suggests the presence of compensatory brain mechanisms. In the present study, we investigated this effect in Parkinson's disease (PD) patients carrying the DRD2 TaqIA A1 allelic variant. This variant may confer an increased risk of developing the disease and/or influence the clinical presentation. During a complex sequential motor task, we evidenced by functional magnetic resonance imaging that A1 allele carriers activated a larger network of bilateral cerebral areas than non-carriers, including cerebellar and premotor regions. Both groups had similar clinical and demographic measures. In addition, their motor performance during the functional magnetic resonance experiment was comparable. Therefore, our conclusions, pending replication in a larger sample, seem to reflect the recruitment of compensatory cerebral resources during motor processing in PD patients carrying the A1 allele. [source]

Sensorimotor network rewiring in mild cognitive impairment and Alzheimer's disease

HUMAN BRAIN MAPPING, Issue 4 2010
Federica Agosta
Abstract This study aimed at elucidating whether (a) brain areas associated with motor function show a change in functional magnetic resonance imaging (fMRI) signal in amnestic mild cognitive impairment (aMCI) and Alzheimer's disease (AD), (b) such change is linear over the course of the disease, and (c) fMRI changes in aMCI and AD are driven by hippocampal atrophy, or, conversely, reflect a nonspecific neuronal network rewiring generically associated to brain tissue damage. FMRI during the performance of a simple motor task with the dominant right-hand, and structural MRI (i.e., dual-echo, 3D T1-weighted, and diffusion tensor [DT] MRI sequences) were acquired from 10 AD patients, 15 aMCI patients, and 11 healthy controls. During the simple-motor task, aMCI patients had decreased recruitment of the left (L) inferior frontal gyrus compared to controls, while they showed increased recruitment of L postcentral gyrus and head of L caudate nucleus, and decreased activation of the cingulum compared with AD patients. Effective connectivity was altered between primary sensorimotor cortices (SMC) in aMCI patients vs. controls, and between L SMC, head of L caudate nucleus, and cingulum in AD vs. aMCI patients. Altered fMRI activations and connections were correlated with the hippocampal atrophy in aMCI and with the overall GM microstructural damage in AD. Motor-associated functional cortical changes in aMCI and AD mirror fMRI changes of the cognitive network, suggesting the occurrence of a widespread brain rewiring with increasing structural damage rather than a specific response of cognitive network. Hum Brain Mapp, 2010. © 2009 Wiley-Liss, Inc. [source]

Crossmodal influences in somatosensory cortex: Interaction of vision and touch

HUMAN BRAIN MAPPING, Issue 1 2010
Jennifer K. Dionne
Abstract Previous research has shown that information from one sensory modality has the potential to influence activity in a different modality, and these crossmodal interactions can occur early in the cortical sensory processing stream within sensory-specific cortex. In addition, it has been shown that when sensory information is relevant to the performance of a task, there is an upregulation of sensory cortex. This study sought to investigate the effects of simultaneous bimodal (visual and vibrotactile) stimulation on the modulation of primary somatosensory cortex (SI), in the context of a delayed sensory-to-motor task when both stimuli are task-relevant. It was hypothesized that the requirement to combine visual and vibrotactile stimuli would be associated with an increase in SI activity compared to vibrotactile stimuli alone. Functional magnetic resonance imaging (fMRI) was performed on healthy subjects using a 3T scanner. During the scanning session, subjects performed a sensory-guided motor task while receiving visual, vibrotactile, or both types of stimuli. An event-related design was used to examine cortical activity related to the stimulus onset and the motor response. A region of interest (ROI) analysis was performed on right SI and revealed an increase in percent blood oxygenation level dependent signal change in the bimodal (visual + tactile) task compared to the unimodal tasks. Results of the whole-brain analysis revealed a common fronto-parietal network that was active across both the bimodal and unimodal task conditions, suggesting that these regions are sensitive to the attentional and motor-planning aspects of the task rather than the unimodal or bimodal nature of the stimuli. Hum Brain Mapp, 2010. © 2009 Wiley-Liss, Inc. [source]

A comparison of Granger causality and coherency in fMRI-based analysis of the motor system

HUMAN BRAIN MAPPING, Issue 11 2009
Andrew S. Kayser
Abstract The ability of functional MRI to acquire data from multiple brain areas has spurred developments not only in voxel-by-voxel analyses, but also in multivariate techniques critical to quantifying the interactions between brain areas. As the number of multivariate techniques multiplies, however, few studies in any modality have directly compared different connectivity measures, and fewer still have done so in the context of well-characterized neural systems. To focus specifically on the temporal dimension of interactions between brain regions, we compared Granger causality and coherency (Sun et al., 2004, 2005: Neuroimage 21:647,658, Neuroimage 28:227,237) in a well-studied motor system (1) to gain further insight into the convergent and divergent results expected from each technique, and (2) to investigate the leading and lagging influences between motor areas as subjects performed a motor task in which they produced different learned series of eight button presses. We found that these analyses gave convergent but not identical results: both techniques, for example, suggested an anterior-to-posterior temporal gradient of activity from supplemental motor area through premotor and motor cortices to the posterior parietal cortex, but the techniques were differentially sensitive to the coupling strength between areas. We also found practical reasons that might argue for the use of one technique over another in different experimental situations. Ultimately, the ideal approach to fMRI data analysis is likely to involve a complementary combination of methods, possibly including both Granger causality and coherency. Hum Brain Mapp, 2009. © 2009 Wiley-Liss, Inc. [source]

Rolandic alpha and beta EEG rhythms' strengths are inversely related to fMRI-BOLD signal in primary somatosensory and motor cortex

HUMAN BRAIN MAPPING, Issue 4 2009
Petra Ritter
Abstract Similar to the posterior alpha rhythm, pericentral (Rolandic) EEG rhythms in the alpha and beta frequency range are referred to as "idle rhythms" indicating a "resting state" of the respective system. The precise function of these rhythms is not clear. We used simultaneous EEG-fMRI during a bimanual motor task to localize brain areas involved in Rolandic alpha and beta EEG rhythms. The identification of these rhythms in the MR environment was achieved by a blind source separation algorithm. Rhythm "strength", i.e. spectral power determined by wavelet analysis, inversely correlated most strongly with the fMRI-BOLD signal in the postcentral cortex for the Rolandic alpha (mu) rhythm and in the precentral cortex for the Rolandic beta rhythm. FMRI correlates of Rolandic alpha and beta rhythms were distinct from those associated with the posterior "classical" alpha rhythm, which correlated inversely with the BOLD signal in the occipital cortex. An inverse correlation with the BOLD signal in the respective sensory area seems to be a general feature of "idle rhythms". Hum Brain Mapp 2009. © 2008 Wiley-Liss, Inc. [source]

fMRI analysis for motor paradigms using EMG-based designs: A validation study

HUMAN BRAIN MAPPING, Issue 11 2007
Anne-Fleur van Rootselaar
Abstract The goal of the present validation study is to show that continuous surface EMG recorded simultaneously with 3T fMRI can be used to identify local brain activity related to (1) motor tasks, and to (2) muscle activity independently of a specific motor task, i.e. spontaneous (abnormal) movements. Five healthy participants performed a motor task, consisting of posture (low EMG power), and slow (medium EMG power) and fast (high EMG power) wrist flexion,extension movements. Brain activation maps derived from a conventional block design analysis (block-only design) were compared with brain activation maps derived using EMG-based regressors: (1) using the continuous EMG power as a single regressor of interest (EMG-only design) to relate motor performance and brain activity, and (2) using EMG power variability as an additional regressor in the fMRI block design analysis to relate movement variability and brain activity (mathematically) independent of the motor task. The agreement between the identified brain areas for the block-only design and the EMG-only design was excellent for all participants. Additionally, we showed that EMG power variability correlated well with activity in brain areas known to be involved in movement modulation. These innovative EMG-fMRI analysis techniques will allow the application of novel motor paradigms. This is an important step forward in the study of both the normally functioning motor system and the pathophysiological mechanisms in movement disorders. Hum Brain Mapp, 2007. © 2007 Wiley-Liss, Inc. [source]

fMRI changes in relapsing-remitting multiple sclerosis patients complaining of fatigue after IFN,-1a injection

HUMAN BRAIN MAPPING, Issue 5 2007
Maria A. Rocca
Abstract If fatigue in multiple sclerosis (MS) is related to an abnormal activation of the sensorimotor brain network, the activity of such a network should vary with varying fatigue. We studied 22 patients treated with interferon beta 1a (IFN,-1a; Avonex, Biogen, Cambridge, MA) with no fatigue (10) and with reversible fatigue (12). fMRI examinations were performed: 1) the same day of IFN,-1a injection (no fatigue; entry), 2) the day after IFN,-1a injection (fatigue; time 1), and 3) 4 days after IFN,-1a injection (no fatigue; time 2). Patients performed a simple motor task with the right, clinically unaffected hand. At time 1, compared with entry and time 2, MS patients with reversible fatigue showed an increased activation of the thalamus bilaterally. In MS patients without fatigue thalamus was more activated at entry than at time 1. In both groups at entry the primary SMC and the SMA were more activated than at times 1 and 2. At entry and time 1, when compared to patients with reversible fatigue, those without showed increased activations of the SII. Conversely, patients with reversible fatigue had increased activations of the thalamus and of several regions of the frontal lobes. An abnormal recruitment of the fronto-thalamic circuitry is associated with IFN,-1a-induced fatigue in MS patients. Hum Brain Mapp, 2007. © 2006 Wiley-Liss, Inc. [source]

fMRI of the lumbar spinal cord during a lower limb motor task

MAGNETIC RESONANCE IN MEDICINE, Issue 2 2004
J. Kornelsen
Abstract This study applied spinal fMRI to the lumbar spinal cord during lower limb motor activity. During active ankle movement, activity was detected in the lumbar spinal cord motor areas and sensory areas bilaterally. During passive ankle movement, activity was detected in the motor and sensory areas in lower lumbar spinal cord segments and motor activity in higher lumbar spinal cord segments. Spinal fMRI detects patterns of activity consistent with known physiology and can be used to reliably assess activity in the lumbar spinal cord during lower limb motor stimulation. This study affirms spinal fMRI as an effective tool for assessing spinal cord function and increases its potential as a clinical tool. Magn Reson Med 52:411,414, 2004. © 2004 Wiley-Liss, Inc. [source]

Effect of external cueing on gait in Huntington's disease

MOVEMENT DISORDERS, Issue 10 2008
Arnaud Delval MD
Abstract In Huntington's disease (HD) patients, gait is characterized by a timing disorder with marked intraindividual variability in temporal gait parameters (caused by the presence of both hyperkinetic and hypokinetic features). We sought to determine the influence of use of a metronome on gait parameters in patients simultaneously performing motor or cognitive tasks that required attentional resources. The objective is to evaluate the influence of rhythmic cues on gait interference during self-regulated walking and a dual task paradigm in HD. Fifteen HD patients and 15 paired controls were asked to walk and simultaneously perform another motor task (carrying a tray with four full glasses) or a cognitive task (counting backwards). We evaluated the effect of a metronome (set at 100% and 120% of the subject's self-determined cadence) in three different task conditions (gait alone, gait + motor task, gait + cognitive task). The use of auditory cues during free gait and dual tasks did not improve kinematic parameters in HD patients, in contrast to the situation for control subjects (improvement in gait speed and cadence but not stride length when the metronome was set at 120% in all conditions). HD patients have difficulty in synchronizing their footsteps with a metronome, mainly due to attentional deficits. © 2008 Movement Disorder Society [source]

Deep brain stimulation and medication for parkinsonian tremor during secondary tasks

MOVEMENT DISORDERS, Issue 8 2007
Molly M. Sturman PhD
Abstract This study examined the efficacy of subthalamic nucleus (STN), deep brain stimulation (DBS), and medication for resting tremor during performance of secondary tasks. Hand tremor was recorded using accelerometry and electromyography (EMG) from 10 patients with Parkinson's disease (PD) and ten matched control subjects. The PD subjects were examined off treatment, on STN DBS, on medication, and on STN DBS plus medication. In the first experiment, tremor was recorded in a quiet condition and during a cognitive task designed to enhance tremor. In the second experiment, tremor was recorded in a quiet condition and during isometric finger flexion (motor task) with the contralateral limb at 5% of the maximal voluntary contraction (MVC) that was designed to suppress tremor. Results showed that: (1) STN DBS and medication reduced tremor during a cognitive task that exacerbated tremor, (2) STN DBS normalized tremor frequency in both the quiet and cognitive task conditions, whereas tremor amplitude was only normalized in the quiet condition, (3) a secondary motor task reduced tremor in a similar manner to STN DBS. These findings demonstrate that STN DBS still suppresses tremor in the presence of a cognitive task. Furthermore, a secondary motor task of the opposite limb suppresses tremor to levels comparable to STN DBS. © 2007 Movement Disorder Society [source]

Posturographic analysis of balance control in patients with essential tremor

MOVEMENT DISORDERS, Issue 2 2006
Marco Bove PhD
Abstract Essential tremor (ET) is a common movement disorder causing an important functional disability. ET is generally regarded as a monosymptomatic disorder, but additional signs may be present. We analyzed postural sway in 19 patients with classic ET and in 19 sex- and age-matched normal controls (NC) to uncover possible abnormalities of balance control. Static posturography was performed with eyes open (EO) and closed during quiet stance and during performance of mental calculation or motor sequence of thumb opposition to the other fingers. No significant differences of center of foot pressure (COP) parameters were observed between patients and controls during quiet standing. Visual deprivation induced a similar worsening of postural sway in both groups. Concomitant performance of a cognitive or motor task did not affect COP area, whereas COP path was significantly modified by the cognitive task in both groups. In all EO conditions, the COP path was significantly lower in NC than in ET, but such offset was related only to the group of ET patients with head tremor. This study demonstrates that balance control is only minimally affected in ET, although patients with head involvement and longer disease duration tend to present a reduced postural stability. The "dual-task effect" is less important in ET than in Parkinson's disease patients. © 2005 Movement Disorder Society [source]

Anatomical and functional brain imaging using high-resolution echo-planar spectroscopic imaging at 1.5 Tesla

NMR IN BIOMEDICINE, Issue 4 2005
Weiliang Du
Abstract High-resolution echo-planar spectroscopic imaging (EPSI) of water resonance (i.e. without water suppression) is proposed for anatomic and functional imaging of the human brain at 1.5,T. Water spectra with a resolution of 2.6,Hz and a bandwidth of 333,Hz were obtained in small voxels (1.7,×,1.7,×,3,mm3) across a single slice. Although water spectra appeared Lorentzian in most of the voxels in the brain, non-Lorentzian broadening of the water resonance was observed in voxels containing blood vessels. In functional experiments with a motor task, robust activation in motor cortices was observed in high-resolution T maps generated from the EPSI data. Shift of the water resonance frequency occurred during neuronal activation in motor cortices. The activation areas appeared to be more localized after excluding the voxels in which the lineshape of the water resonance had elevated T and became more non-Lorentzian during the motor task. These preliminary results suggest that high-resolution EPSI is a promising tool to study susceptibility-related effects, such as BOLD contrast, for improved anatomical and functional imaging of the brain. Copyright © 2005 John Wiley & Sons, Ltd. [source]

Intermanual transfer of a new writing occupation in young adults without disability

OCCUPATIONAL THERAPY INTERNATIONAL, Issue 1 2002
Megan E. Andree
Abstract It has been shown that acquisition of a skill by one hand is facilitated by previous learning of the same skill with the other hand. This is called intermanual transfer of learning, or cross-education. The investigators examined intermanual transfer of occupation of writing in a group of 10 right-handed subjects with no known motor disabilities. Subjects learned to perform a novel occupation of writing a foreign alphabet letter with either their right or left hand. Later, subjects reproduced the skill with the practised and unpractised contralateral hand. Pen movements and surface electromyography of the first dorsal interosseus muscle were recorded to assess the transfer of learning. Analysis revealed an almost full transfer of the learned motor task between hands in either left-to-right or right-to-left direction when movement time and movement size were compared. This indicates that transfer did not depend on hand dominance. These findings suggest that a task already learned by one hand can positively influence the learning of the same task by the other hand. The results have important implications for occupational therapy , namely, that activities comprising tasks previously learned by one hand would be more effective in facilitating improved performance by the other hand than activities comprising previously unlearned tasks in the case of retraining skills in patients with amputation or hemiplegia. Because the participants in this study were a small number of college students, research should be carried out with larger participant pools and participants with disabilities to consolidate the findings. Copyright © 2002 Whurr Publishers Ltd. [source]

Interlimb coordination differentiates Brazilian children from two socioeconomic settings

PEDIATRICS INTERNATIONAL, Issue 3 2010
Tatiana G. Bobbio
Abstract Background:, The aim of the present study was to test the notion that Brazilian children entering private school have a motor function advantage over those entering their first year in public school. Methods:, Four hundred and two children from the two cultural settings were examined for motor function in the first and 10th month of school (first grade). Participants were assessed based on age-level standards and by total score for all items for children 3 to 7 years of age. Results:, The private school group outperformed their public setting peers on the first and second assessment; both groups improved over the school year. The most interesting outcome was the type of motor task that most clearly differentiated the groups: activities requiring gross motor (interlimb) coordination. Conclusion:, Among the recommendations given, it is suggested that motor skill activities, especially those involving interlimb coordination, be included with any type of motor programming for young children. [source]

The instructed context of a motor task modulates covert response preparation and shifts of spatial attention

PSYCHOPHYSIOLOGY, Issue 3 2009
Elena Gherri
Abstract We investigated how covert response preparation is modulated by the instructed cognitive context of a motor task. Participants prepared left-hand or right-hand movements toward or away from the body midline, as indicated by a response cue (S1) presented prior to a go/no-go stimulus (S2). Different participants were instructed that response cues specified the response hand or movement direction, respectively. This emphasis on effector versus movement direction selection modulated lateralized ERP components triggered during the S1,S2 interval. Attention shifts during movement preparation were assessed by measuring ERPs to irrelevant visual probes. Enhanced N1 components were found for probes near the effector when effector selection was emphasized, but for probes near the movement target location when movement direction selection was emphasized. Results demonstrate strong top-down contextual biases on motor control and on the locus of spatial attention during response preparation. [source]

Low- and high-level controlled processing in executive motor control tasks in 5,6-year-old children at risk of ADHD

THE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 7 2003
Ariane C. Kalff
Background: The scant research on the characteristics of Attention-Deficit/Hyperactivity Disorder (ADHD) in kindergarten years curtails progress on early assessment of ADHD. Method: By screening a general population sample of 1317 five- to six-year-old children, four groups of children were selected. The performance of 30 children later diagnosed with ADHD was compared with 74 children later diagnosed with ,borderline ADHD' (children exhibiting all ADHD symptoms but without disruptions on two situations), 113 children later diagnosed with other psychopathology, and 126 healthy controls on computerised motor control tasks involving low- and high-level controlled processing. In addition, motor control was compared with movement speed. Results: The children at risk of ADHD were in general less accurate and more variable in their movements than the children with other psychopathology and healthy controls. Under conditions of high-level controlled processing, the children at risk of ADHD were disproportionately more inaccurate and had a more unstable performance with their preferred hand than the other children. In addition, linear effects were found, with the children at risk of ADHD having the worst performance, followed by the children with ,borderline ADHD', and then both groups of control children. No significant group differences were found in movement speed. Conclusions: The main findings are interpreted as evidence for a specific deficit in high-level controlled processing in young children at risk of ADHD, now found in a motor task, rather than a response task. Furthermore, the results support the notion that ADHD represents a dimensional trait. In addition, problems in movement control (the need to allocate attentional capacity) rather than problems in movement speed distinguish children at risk of ADHD from other children. The findings are interpreted as evidence that higher-order executive processes, such as self-control and self-regulation, are already affected early in the development of ADHD. [source]

Early imaging correlates of subsequent motor recovery after stroke,

ANNALS OF NEUROLOGY, Issue 5 2009
Randolph S. Marshall MS
Objective To determine whether functional magnetic resonance imaging activation obtained in the first few days after stroke correlates with subsequent motor recovery. Methods Twenty-three patients with hemiparesis after first-time stroke were scanned at 2.0 ± 0.9 days while performing a simple motor task. We defined recovery as the change in Fugl,Meyer score from time of scan to approximately 3 months later (90 ± 8 days). We performed three different tests to assess correlations between brain activation and change in Fugl,Meyer score: (1) multivariate (most sensitive to spatially diffuse activation); (2) voxel-wise Statistical Parametric Mapping (most sensitive to focal activation), and (3) primary motor cortex region-of-interest analysis (most sensitive to average activation within this region). All tests controlled for initial stroke severity and lesion volume, as well as other established clinical variables. Results The multivariate test was significant [F (595, 4,934) = 1.93; p < 0.001]. The Statistical Parametric Mapping test detected two small clusters of focal activity located in the ipsilesional postcentral gyrus and cingulate cortex (p < 0.05, corrected). The region-of-interest test was not significant. Interpretation There is a pattern of brain activation present in the first few days after stroke, of which the postcentral gyrus and cingulate cortex are a part, that correlates with subsequent motor recovery. This result suggests that there are recovery processes engaged early after stroke that could provide a target for intervention. Ann Neurol 2009;65:596,602 [source]

Working memory for ballet moves and spatial locations in professional ballet dancers

APPLIED COGNITIVE PSYCHOLOGY, Issue 2 2010
Antonio Cortese
The aim of the present study was to investigate working memory for ballet moves in expert dancers. Experiment 1 showed that a concurrent spatial task did not interfere with the recall of a sequence of ballet moves when these were encoded alone without being associated with spatial locations. Experiment 2 showed that a concurrent motor task selectively interfered with the recall of ballet moves while neither a concurrent motor task nor a spatial task affected recall of the specific locations where each ballet move had to be performed. Experiment 3 showed that spatial interference affected recall of sequences of locations when these were encoded alone. Finally, in Experiment 4, a similarity effect for patterned ballet movements was shown. Taken together results show that spatial interference does not affect short-term memory for ballet moves thus suggesting that working memory might contain a system for motor configurations. Copyright © 2009 John Wiley & Sons, Ltd. [source]

Functional changes of the cortical motor system in hereditary spastic paraparesis

ACTA NEUROLOGICA SCANDINAVICA, Issue 3 2009
B. Koritnik
Background,,, Hereditary spastic paraparesis (HSP) is a heterogeneous group of disorders characterized by progressive bilateral lower limb spasticity. Functional imaging studies in patients with corticospinal tract involvement have shown reorganization of motor circuitry. Our study investigates functional changes in sensorimotor brain areas in patients with HSP. Methods,,, Twelve subjects with HSP and 12 healthy subjects were studied. Functional magnetic resonance imaging (fMRI) was used to measure brain activation during right-hand finger tapping. Image analysis was performed using general linear model and regions of interest (ROI)-based approach. Weighted laterality indices (wLI) and anterior/posterior indicies (wAI and wPI) were calculated for predefined ROIs. Results and discussion,,, Comparing patients and controls at the same finger-tapping rate (1.8 Hz), there was increased fMRI activation in patients' bilateral posterior parietal cortex and left primary sensorimotor cortex. No differences were found when comparing patients and controls at 80% of their individual maximum tapping rates. wLI of the primary sensorimotor cortex was significantly lower in patients. Subjects with HSP also showed a relative increase in the activation of the posterior parietal and premotor areas compared with that of the primary sensorimotor cortex. Our findings demonstrate an altered pattern of cortical activation in subjects with HSP during motor task. The increased activation probably reflects reorganization of the cortical motor system. [source]

Development of motor speed and associated movements from 5 to 18 years

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 3 2010
THEO GASSER PHD
Aim, To study the development of motor speed and associated movements in participants aged 5 to 18 years for age, sex, and laterality. Method, Ten motor tasks of the Zurich Neuromotor Assessment (repetitive and alternating movements of hands and feet, repetitive and sequential finger movements, the pegboard, static and dynamic balance, diadochokinesis) were administered to 593 right-handed participants (286 males, 307 females). Results, A strong improvement with age was observed in motor speed from age 5 to 10, followed by a levelling-off between 12 and 18 years. Simple tasks and the pegboard matured early and complex tasks later. Simple tasks showed no associated movements beyond early childhood; in complex tasks associated movements persisted until early adulthood. The two sexes differed only marginally in speed, but markedly in associated movements. A significant laterality (p<0.001) in speed was found for all tasks except for static balance; the pegboard was most lateralized, and sequential finger movements least. Associated movements were lateralized only for a few complex tasks. We also noted a substantial interindividual variability. Interpretation, Motor speed and associated movements improve strongly in childhood, weakly in adolescence, and are both of developmental relevance. Because they correlate weakly, they provide complementary information. [source]

Motor impairments in young children with cerebral palsy: relationship to gross motor function and everyday activities

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 9 2004
Sigrid Østensjø MSc PT
In this study we assessed the distribution of spasticity, range of motion (ROM) deficits, and selective motor control problems in children with cerebral palsy (CP), and examined how these impairments relate to each other and to gross motor function and everyday activities. Ninety-five children (55 males, 40 females; mean age 58 months, SD18 months, range 25 to 87 months) were evaluated with the modified Ashworth scale (MAS), passive ROM, the Selective Motor Control scale (SMC), the Gross Motor Function Measure (GMFM), and the Pediatric Evaluation of Disability Inventory (PEDI). Types of CP were hemiplegia (n=19), spastic diplegia (n=40), ataxic diplegia (n=4), spastic quadriplegia (n=16), dyskinetic (n=9), and mixed type (n=7). Severity spanned all five levels of the Gross Motor Function Classification System (GMFCS). The findings highlight the importance of measuring spasticity and ROM in several muscles and across joints. Wide variability of correlations of MAS, ROM, and SMC indicates a complex relationship between spasticity, ROM, and selective motor control. Loss of selective control seemed to interfere with gross motor function more than the other impairments. Further analyses showed that motor impairments were only one component among many factors that could predict gross motor function and everyday activities. Accomplishment of these activities was best predicted by the child's ability to perform gross motor tasks. [source]

Neuromotor development from 5 to 18 years.

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 7 2001
Part 1: timed performance
Timed performance in specific motor tasks is an essential component of a neurological examination applied to children with motor dysfunctions. This article provides centile curves describing normal developmental course and interindividual variation of timed performances of non-disabled children from 5 to 18 years. In a cross-sectional study (n=662) the following motor tasks were investigated: repetitive finger movements, hand and foot movements, alternating hand and foot movements, sequential finger movements, pegboard, and dynamic and static balance. Intraobserver, interobserver, and test-retest reliability for timed measurements were moderate to high. Timed performances improved throughout the entire prepubertal period, but differed among various motor tasks with respect to increase in speed and when the,adolescent plateau' was reached. Centile curves of timed performance displayed large interindividual variation for all motor tasks. At no age were clinically relevant sex differences noted, nor did socioeconomic status significantly correlate with timed performance. Our results demonstrate that timed motor performances between 5 and 18 years are characterized by a long-lasting developmental change and a large interindividual variation. Therefore, a well standardized test instrument, and age-specific standards for motor performances are necessary preconditions for a reliable assessment of motor competence in school-age children. [source]

Age-related white matter lesions are associated with reduction of the apparent diffusion coefficient in the cerebellum

EUROPEAN JOURNAL OF NEUROLOGY, Issue 9 2007
P. Bugalho
Cerebellar apparent diffusion coefficient (ADC) was found to be increased after acute cerebral hemispheric stroke. There are no data on cerebellar ADC changes in patients with chronic, age-related white matter lesions (ARWML). We aimed to determine longitudinal ADC variations on cerebral hemispheric and cerebellar white matter regions of patients with ARWML in order to study relations between ADC changes in both regions. ADC was measured serially (1-year interval) on lesioned periventricular frontal white matter, frontal and parietoccipital normal appearing white matter and middle cerebellar peduncles, on 19 aged patients with ARWML, which also underwent gait assessment. We compared regional ADC at 0 and 1 year and calculated variation percentages for each region. Correlation analysis was made between ADC variation in cerebellar regions and in contralateral hemispheric regions and between cerebellar ADC at 1 year and walking speed. After 1 year, ADC was higher on lesioned periventricular frontal white matter and lower on cerebellar regions. ADC variations on these regions were negatively correlated. Cerebellar ADC measured after 1 year was positively correlated with walking speed. This suggests a link between vascular disease progression inside frontal lesions and ADC reduction in contralateral cerebellar peduncles. Chronic ischemia in frontal white matter could have interrupted frontal-cerebellar circuits, producing hypometabolism in cerebellar regions (and worse performance on motor tasks), decreased perfusion and hence ADC reduction. [source]

fMRI analysis for motor paradigms using EMG-based designs: A validation study

Differential activity patterns in the masseter muscle under simulated clenching and grinding forces

JOURNAL OF ORAL REHABILITATION, Issue 8 2005
H. J. SCHINDLER
summary, The aim of this study was to investigate (i) whether the masseter muscle shows differential activation under experimental conditions which simulate force generation during clenching and grinding activities; and (ii) whether there are (a) preferentially active muscle regions or (b) force directions which show enhanced muscle activation. To answer these questions, the electromyographic (EMG) activity of the right masseter muscle was recorded with five intramuscular electrodes placed in two deep muscle areas and in three surface regions. Intraoral force transfer and force measurement were achieved by a central bearing pin device equipped with three strain gauges (SG). The activity distribution in the muscle was recorded in four different mandibular positions (central, left, right, anterior). In each position, maximum voluntary contraction (MVC) was exerted in vertical, posterior, anterior, medial and lateral directions. The investigated muscle regions showed different amount of EMG activity. The relative intensity of the activation, with respect to other regions, changed depending on the task. In other words, the muscle regions demonstrated heterogeneous changes of the EMG pattern for the various motor tasks. The resultant force vectors demonstrated similar amounts in all horizontal bite directions. Protrusive force directions revealed the highest relative activation of the masseter muscle. The posterior deep muscle region seemed to be the most active compartment during the different motor tasks. The results indicate a heterogeneous activation of the masseter muscle under test conditions simulating force generation during clenching and grinding. Protrusively directed bite forces were accompanied by the highest activation in the muscle, with the posterior deep region as the most active area. [source]

Blood Oxygen Level Dependent Response and Spatial Working Memory in Adolescents With Alcohol Use Disorders

ALCOHOLISM, Issue 10 2004
Susan F. Tapert
Background: Previous studies have suggested neural disruption and reorganization in young and older adults with alcohol use disorders (AUD). However, it remains unclear at what age and when in the progression of AUD changes in brain functioning might occur. Methods: Alcohol use disordered (n= 15) and nonabusing (n= 19) boys and girls aged 15 to 17 were recruited from local high schools. Functional magnetic resonance imaging data were collected after a minimum of 5 days' abstinence as participants performed spatial working memory and simple motor tasks. Results: Adolescents with AUD showed greater brain response to the spatial working memory task in bilateral parietal cortices and diminished response in other regions, including the left precentral gyrus and bilateral cerebellar areas (clusters ,943 ,l; p < 0.05), although groups did not differ on behavioral measures of task performance. No brain response differences were observed during a simple finger-tapping task. The degree of abnormality was greater for teens who reported experiencing more withdrawal or hangover symptoms and who consumed more alcohol. Conclusions: Adolescents with AUD show abnormalities in brain response to a spatial working memory task, despite adequate performance, suggesting that subtle neuronal reorganization may occur early in the course of AUD. [source]