Delay in initiation and termination of muscle contraction, motor impairment, and physical disability in upper limb hemiparesis

Chae, ME John; Yang, Guang; Park, Byung Kyu; Labatia, Ihab

doi:10.1002/mus.10061

Cited by 116 publications

(88 citation statements)

References 27 publications

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“…This finding suggests that inhibitory intracortical pathways play an important role in mediating muscle relaxation. The functional implication of this finding is that disturbances in the cortical inhibitory pathways may lead to difficulties in terminating the voluntary muscle relaxation or ''letting go'' such as after stroke (Seo et al 2009;Chae et al 2002).…”

Section: Resultsmentioning

confidence: 94%

Contribution of intracortical inhibition in voluntary muscle relaxation

et al. 2012

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Terminating a voluntary muscle contraction is an important aspect of motor control, and yet, its neurophysiology is unclear. The objective of this study was to determine the role of short-interval intracortical inhibition (SICI) by comparing SICIs during relaxation from a power grip versus during a sustained power grip at the matching muscle activity level. Right-handed healthy young adults gripped and relaxed from power grip following auditory cues. The relaxation period was determined as the time for the flexor digitorum superficialis (FDS) muscle to reach its pre-contraction baseline level after the cue to relax. SICI during relaxation was obtained at different times into the relaxation period in two separate studies (70, 80, 90 % into relaxation in Study 1; 25, 50, 75 % into relaxation in Study 2). In addition, SICI during sustained contraction was assessed while subjects maintained a power grip at the matching FDS EMG levels (obtained during relaxation, for both Studies). Results showed that the mean SICI was greater during relaxation than during sustained contraction at the matching muscle activity level in both Studies (p < 0.05), indicating increased activation of intracortical inhibitory circuits for muscle relaxation. SICI gradually increased from 25 to 50 and 75 % into relaxation (Study 2, p < 0.05), but did not change from 70 to 80 and 90 % into relaxation (Study 1). MEP decreased with progression of relaxation (p < 0.05) in both Studies, reflecting gradual decreases in corticomotor excitability. This work supports the hypothesis that relaxation from a voluntary muscle contraction involves inhibitory activity in the primary motor cortex.

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Section: Resultsmentioning

confidence: 94%

Contribution of intracortical inhibition in voluntary muscle relaxation

et al. 2012

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“…In a previous study, which compared the delay in initiation and termination of post-stroke patients, Chae et al (2001) reported that the delay in initiation or termination of muscle contractions was significantly greater for the paretic than in the non-paretic limbs 16) . Similarly, delay in termination of muscle contraction was significantly greater than delay in initiation of muscle contraction for both the paretic and non-paretic limbs.…”

Section: Discussionmentioning

confidence: 99%

Characteristics of Driving Reaction Time of Elderly Drivers in the Brake Pedal Task

Shin

Lee

2012

J Phys Ther Sci

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Abstract. [Purpose] Driving is a complex activity involving cognitive and motor skills. It is an essential component of daily life for older adults. However, aging may decrease a driver's psychomotor performance and increase the risk of traffic accidents. Driving reaction time (DRT) requires visuo-motor coordination and fast DRTS are needed to cope with unexpected conditions or traffic lights. The purpose of the current study was to compare the DRT of elderly drivers and young drivers using a tri-axial accelerometer and a foot switch.[Methods] Twenty-four subjects (younger=12, elderly=12) participated in this study. DRT was measured with a tri-axial accelerometer and foot switch. DRT was classified by initiation and termination as on or off according to contact with the brake pedal during the brake pedal task.[Results] The ANOVA model for accelerometer-DRT yielded significant main effects for phase, but not for axis. Termination was delayed significantly more than initiation. The elderly group showed significantly more delay than the younger group. In the elderly group, termination was delayed more than initiation, but there was no difference in delay between initiation and termination in the young group . In foot switch-DRT, termination was delayed much more than initiation in both groups (p<0.05). The elderly group showed significantly more delay than the young group. [Conclusion] We suggest that the driving ability of elderly drivers can be assessed with reasonable accuracy using accelerometer-DRT, which minimizes the expense and risk associated with on-road assessments of this population.

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“…The latter was evaluated by ANOVA and post hoc (Tukey) test of the difference in PI among different FT scores. In view of multiple comparisons, the level of significance was adjusted and defined as P \ 0.01 [3]. All statistical analyses were performed using SPSS ver.16 (SPSS Inc., USA).…”

Section: Analysis and Statisticsmentioning

confidence: 99%

Quantification of bradykinesia during clinical finger taps using a gyrosensor in patients with Parkinson’s disease

Kim

Lee

Kwon

et al. 2010

Med Biol Eng Comput

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This study aims to develop a quantitative measure of bradykinesia which can be conveniently used during clinical finger taps test in patients with Parkinson's disease. A miniature, light-weight gyrosensor free from gravitational artifact was used for measurement of finger taps in order to impose minimal constraint on patients. Forty Parkinson's disease patients and 14 age-matched control subjects participated in the experiments. Subjects' finger taps in both right and left hands were scored by two independent neurologists according to the unified Parkinson's disease rating scale and were also measured by a gyrosensor. Four performance indices were derived from the gyrosensor signal of the index finger. All indices showed significant differences between control and patients (P < 0.001) and also significant correlations with the clinical finger taps score (r = -0.73 to -0.80, P < 0.001). ANOVA showed significant differences in all indices among different finger taps scores (P < 0.001), and post hoc tests showed significant differences in indices between most pairs of non-neighboring and part of neighboring pairs of finger taps scores (P < 0.01). The results suggest that indices from a gyrosensor can be used as quantitative measures of bradykinesia during the finger taps test.

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Delay in initiation and termination of muscle contraction, motor impairment, and physical disability in upper limb hemiparesis

Cited by 116 publications

References 27 publications

Contribution of intracortical inhibition in voluntary muscle relaxation

Contribution of intracortical inhibition in voluntary muscle relaxation

Characteristics of Driving Reaction Time of Elderly Drivers in the Brake Pedal Task

Quantification of bradykinesia during clinical finger taps using a gyrosensor in patients with Parkinson’s disease

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