Asymmetry of motor cortex excitability during a simple motor task: relationships with handedness and manual performance

After prolonged practice (1300 10-sec trials) the tapping speed of the nonpreferred hand reached that of the preferred hand on a simple finger-tapping task. Analysis of the intertap intervals showed the variability of the duration of intertap intervals was smaller for the preferred than for the nonpreferred hand; the difference was not affected by the prolonged practice for N = 1.

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Intervention Models in Functional Connectivity Identification Applied to fMRI

International Journal of Biomedical Imaging ◽

10.1155/ijbi/2006/27483 ◽

2006 ◽

Vol 2006 ◽

pp. 1-7 ◽

Cited By ~ 6

Author(s):

João Ricardo Sato ◽

Daniel Yasumasa Takahashi ◽

Ellison Fernando Cardoso ◽

Maria da Graça Morais Martin ◽

Edson Amaro Júnior ◽

...

Keyword(s):

Structural Equation ◽

Motor Task ◽

Equation Modeling ◽

Association Measure ◽

Intervention Models ◽

Simple Motor ◽

Simple Motor Task ◽

Stationarity Conditions ◽

Neuroimaging Techniques ◽

Illustrative Application

Recent advances in neuroimaging techniques have provided precise spatial localization of brain activation applied in several neuroscience subareas. The development of functional magnetic resonance imaging (fMRI), based on the BOLD signal, is one of the most popular techniques related to the detection of neuronal activation. However, understanding the interactions between several neuronal modules is also an important task, providing a better comprehension about brain dynamics. Nevertheless, most connectivity studies in fMRI are based on a simple correlation analysis, which is only an association measure and does not provide the direction of information flow between brain areas. Other proposed methods like structural equation modeling (SEM) seem to be attractive alternatives. However, this approach assumes prior information about the causality direction and stationarity conditions, which may not be satisfied in fMRI experiments. Generally, the fMRI experiments are related to an activation task; hence, the stimulus conditions should also be included in the model. In this paper, we suggest an intervention analysis, which includes stimulus condition, allowing a nonstationary modeling. Furthermore, an illustrative application to real fMRI dataset from a simple motor task is presented.

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Motor cortex excitability and fatigue in multiple sclerosis: a transcranial magnetic stimulation study

Multiple Sclerosis Journal ◽

10.1191/1352458505ms1163oa ◽

2005 ◽

Vol 11 (3) ◽

pp. 316-321 ◽

Cited By ~ 82

Author(s):

J Liepert ◽

D Mingers ◽

C Heesen ◽

T Bäumer ◽

C Weiller

Keyword(s):

Multiple Sclerosis ◽

Transcranial Magnetic Stimulation ◽

Motor Cortex ◽

Magnetic Stimulation ◽

Primary Motor Cortex ◽

Motor Task ◽

Time Interval ◽

Membrane Excitability ◽

Motor Cortex Excitability ◽

Fatigue Severity

We investigated electrophysiological correlates of fatigue in patients with multiple sclerosis (MS). Transcranial magnetic stimulation (TMS) was used to explore motor excitability in three groups of subjects: MS patients with fatigue (MS-F), MS patients without fatigue (MS-NF) and healthy control subjects. All participants had to perform a fatiguing hand-grip exercise. TMS was performed prior to and after the exercise. Prior to the motor task, MS-F patients had less inhibition in the primary motor cortex compared to both other groups. Postexercise, intracortical inhibition was still reduced in the MS-F patients compared to the MS-NF patients. In MS-F patients the postexercise time interval for normalization of the motor threshold was correlated with the fatigue severity. We conclude that MS patients with fatigue have an impairment of inhibitory circuits in their primary motor cortex. The results also indicate that fatigue severity is associated with an exercise-induced reduction of membrane excitability.

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Stereotype Threat Effect on a Simple Motor Task: An Investigation of the Visuo-Spatial Working Memory

Research Quarterly for Exercise and Sport ◽

10.1080/02701367.2020.1826391 ◽

2020 ◽

pp. 1-6

Author(s):

Raphael Laurin ◽

Maxinse Renard-Moulard ◽

Carole Cometti

Keyword(s):

Working Memory ◽

Stereotype Threat ◽

Spatial Working Memory ◽

Motor Task ◽

Simple Motor ◽

Threat Effect ◽

Simple Motor Task

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Reversal Phenomenon in a Simple Motor Task: Evidence for an Indirect Model

Conference Proceedings. 2nd International IEEE EMBS Conference on Neural Engineering, 2005. ◽

10.1109/cne.2005.1419560 ◽

2005 ◽

Author(s):

N. Leibowitz ◽

A. Karniel

Keyword(s):

Motor Task ◽

Simple Motor ◽

Reversal Phenomenon ◽

Simple Motor Task

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Subjective Definitions of Tension

Perceptual and Motor Skills ◽

10.2466/pms.1976.43.2.636 ◽

1976 ◽

Vol 43 (2) ◽

pp. 636-638 ◽

Cited By ~ 1

Author(s):

Jeffrey R. Cram ◽

Edwin Lackey

Keyword(s):

Muscle Tension ◽

Motor Task ◽

Proprioceptive Information ◽

Simple Motor ◽

Simple Motor Task ◽

Definition Of

To examine the type of proprioceptive information which subjects include in the definition of tension, 52 subjects were asked to indicate the location of where they felt tension while engaging in a simple motor task. Responses indicated that tendon stretch, muscle tension, and other cues are utilized in the subject's definition of tension.

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