Investigating the cortical origins of motor overflow

Hoy, Kate Elizabeth; Fitzgerald, Paul B.; Bradshaw, John L.; Armatas, Christine; Georgiou‐Karistianis, Nellie

doi:10.1016/j.brainresrev.2004.07.013

Cited by 142 publications

(132 citation statements)

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“…Our study is of interest because the task that subjects purposely performed (right index finger abduction) was similar in the two conditions, yet the (inadvertent) output of the left hand differed depending on its orientation. In review papers concerning contralateral activation (Hoy et al, 2004;Carson, 2005; Cincotta and Ziemann, 2008), associated activity is often implicitly connected with the homologous muscle. Our observations suggest that the direction of contralateral associated activity is organized according to movement direction rather than in relation to active muscle identities.…”

Section: Discussionmentioning

confidence: 99%

“…This implies that the small difference in direction sensitivity during the brief contractions is very likely attributable to lack of statistical power and not to a difference in command strategy between brief and sustained contractions. Several reviews (Hoy et al, 2004;Carson, 2005;Cincotta and Ziemann, 2008) discuss the possible neuronal pathways involved in associated activity. In short, the models attribute associated activity to activation coming through ipsilateral pathways, contralateral pathways, or an interaction between the ipsilateral and contralateral areas [Zijdewind et al (2006), their Fig.…”

Section: Discussionmentioning

confidence: 99%

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Inadvertent Contralateral Activity during a Sustained Unilateral Contraction Reflects the Direction of Target Movement

Post¹,

Bakels²,

Zijdewind³

2009

J. Neurosci.

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Strong unilateral contractions are accompanied by excitatory effects to the ipsilateral cortex. This activity can even result in overt contractions of muscles in the contralateral limb. We used this inadvertent, associated activity to study whether the cortical presentation of movements is organized in a directional-related or a muscle-related reference frame. We assessed the contralateral activation for the left index finger during a sustained maximal abduction of the right index finger. In the first experiment, both hands were held vertically in a symmetrical orientation, and in the second experiment the hands were in an asymmetrical orientation (left hand, palm downward; right hand, vertical). In both experiments, the direction of the contralateral associated contraction was upward, i.e., in the symmetrical hand orientation the contralateral force increased mainly in abduction direction, whereas in the asymmetrical hand orientation the contralateral force increased in the extension direction. Thus, the contralateral contractions reflected the direction of the target movement rather than simply the activity of the muscles activated on the target side. These observations provide strong evidence that motor commands are organized in an extrinsic, direction-related reference frame, as opposed to an internal muscle-related reference frame.

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Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Inadvertent Contralateral Activity during a Sustained Unilateral Contraction Reflects the Direction of Target Movement

Post¹,

Bakels²,

Zijdewind³

2009

J. Neurosci.

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“…There is evidence that motor overflow is due to insufficient interhemispheric inhibition via the corpus callosum. [17][18][19] Better movement quality of females could be interpreted in two ways: first, the female brain is more capable of inhibitory processes; second, this interhemispheric inhibition is a maturational process, and females are advanced by almost 2 years in bone age and puberty. To address this, the current researchers analyzed contralateral AMs for a group of adults (n=145) at ages 45 to 55 years and found no sex difference (p=0.47).…”

Section: Discussionmentioning

confidence: 99%

Quantitative reference curves for associated movements in children and adolescents

Gasser

Rousson

Caflisch

et al. 2007

Develop Med Child Neuro

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Intensity of contralateral associated movements (AMs) is a measure of movement quality assessed using frequency and degree of AMs. A sample of 593 right-handed participants without disability (286 males, 307 females; aged 5y-18y 6mo) was studied with the Zurich Neuromotor Assessment (ZNA). The ZNA is a standardized testing procedure which assesses performance on standardized motor tasks according to timed performance and frequency and degree of AMs. In contrast to frequency and degree, intensity of AMs allowed the calculation of centiles which were quasi-continuous. Centile curves of contralateral AMs for the ZNA and data on inter-and intraobserver reliability are presented. The significance of age, sex, and side differences are discussed. Intensity of AMs offers clinical and scientific advantages for measurement of movement quality. There is a decrease of AMs with age depending on the complexity of tasks. Females showed consistently fewer AMs than males, whereas only minor side differences were shown.In children and adolescents with mild-to-moderate motor dysfunction, timed performance and movement quality for motor tasks need to be assessed reliably. Associated movements (AMs) are an important indicator of movement quality, 1,2 but good reliability is difficult to achieve. Major obstacles are standardization of assessment, scoring of AMs, and training of examiners.Various approaches have been pursued to assess AMs. The finger-lifting method requires the child to move a specified finger. [3][4][5] Using the clip-pinching method, AMs in the contralateral hand are judged when the child exhibits some pressure with the thumb and finger. 4,5 Data for AMs in motor tasks such as finger opposition, diadochokinesis, or walking on heels were also reported. These studies improved understanding of the development of movement quality. 7,8 However, they provided only qualitative, at best semi-quantitative information, and interobserver and test-retest reliability was mostly low. [9][10][11] Largo et al. presented the Zurich Neuromotor Assessment (ZNA) 12 as a standardized test battery with reference curves for timed performance. The ZNA comprises repetitive and alternating movements with hands and feet, repetitive and sequential finger movements, static and dynamic balance, diadochokinesis, and stress gaits. In a companion paper, 2 AMs were analyzed and rated according to frequency (11 levels, indicating the percentage of time with AMs) and degree (four levels, from no movement to marked movements). A normal range across age was provided, as a probability that a child exceeds some value, separately for frequency and degree. This formalization is not easy to use and interpretation of two ratings is not obvious. Centile curves, as for timed performance, were thought to be preferable. The separate rating of frequency and degree has been chosen to facilitate a standardized and accurate assessment of AMs. Thus, these two ratings were combined into one index of severity of AMs, called 'intensity of AMs', by multiplying the two. Th...

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“…In addition to cross facilitation, other hypotheses that may explain the results observed in this study are the theory of motor overflow (TMO) 9,14 and the summation of proprioceptive inputs (SPI) 10 . According to the TMO, when a portion of the brain is activated, other parts are also stimulated 9 , which demonstrates that when a cortical region is activated due to voluntary contraction, the same area in the opposite hemisphere may be activated 14 . Another theory to explain the effects of remote muscle contractions is summation of proprioceptive inputs to the motor cortex 28 .…”

Section: Discussionmentioning

confidence: 99%

“…This phenomenon has been widely investigated; however, most studies investigating the effects of remote voluntary contraction have examined the influence of upper limb contraction on the performance of lower limb tasks and vice versa 9,12 , as well as strategies such as jaw clenching and Valsava maneuver 13 . In these situations, the observed increase in performance is due to hypotheses such as theory of motor overflow (TMO) 9,14 and the summation of proprioceptive inputs (SPI) 10 . However, Weineck 8 has suggested that the increase in performance by simultaneous contraction of contralateral muscles performing opposite movements might be explained (at least in part) by the contralateral coactivation phenomenon, although, there is a gap in the literature about the effects of contralateral coactivation on acute performance.…”

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confidence: 99%

Acute effects of maximal isometric muscle action of the elbow extensors on contralateral dynamic task of the elbow flexors: a pilot study

Teixeira

Cortes

Evangelista

et al. 2017

Motriz: rev. educ. fis.

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-Aim: the aim was to investigate the influence of a maximal isometric muscle action of the elbow extensors on the contralateral dynamic task of the elbow flexors. Methods: Seventeen recreationally trained men (23.3 ± 4.9 yrs, BMI: 24.8 ± 2.2 Kg/m²) underwent two randomized different testing sessions separated by one week. In the control session (CON) all subjects performed a maximum number of repetitions test (RMs) at 75%1RM using the right elbow flexors. The experimental session (EXP) was similar to the CON; however, all subjects were instructed to perform RMs at 75%1RM by using the right elbow flexors and maintaining the maximal voluntary contraction of the left elbow extensors during the test. RMs, rating of perceived exertion (RPE), and training volume (TV) were measured and compared between sessions. Results: The EXP showed a significant 10.4% increase on the RMs (13.8 vs. 12.5, p < 0.001, d = 0.44) and 12.1% increase in TV (238.0 vs. 212.4 kg, p < 0.001, d = 0.43) than CON. No differences were observed for RPE between sessions. Conclusion: The maximum voluntary contraction of the left elbow extensors increased the RMs of the contralateral elbow flexors, reflecting a higher TV, and no differences in the RPE. Our results suggest that the investigated method may be a viable and practical alternative to increase the acute strength performance of elbow flexors when using submaximal loads.

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Investigating the cortical origins of motor overflow

Cited by 142 publications

References 121 publications

Inadvertent Contralateral Activity during a Sustained Unilateral Contraction Reflects the Direction of Target Movement

Inadvertent Contralateral Activity during a Sustained Unilateral Contraction Reflects the Direction of Target Movement

Quantitative reference curves for associated movements in children and adolescents

Acute effects of maximal isometric muscle action of the elbow extensors on contralateral dynamic task of the elbow flexors: a pilot study

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