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Neural activation and functional connectivity during motor imagery of bimanual everyday actions.

Szameitat AJ, McNamara A, Shen S, Sterr A - PLoS ONE (2012)

Bottom Line: We conclude that in MI of everyday actions intermanual coordination demands are primarily met by changes in connectivity between areas and only moderately, if at all, by changes in the amount of neural activity.These results are the first characterization of the neuroanatomical correlates of bimanual coordination demands in MI.The findings extent our understanding of the motor system and may aid the development of clinical neurorehabilitation approaches based on mental practice.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology, Ludwig Maximilians University, Munich, Germany. szameitat@psy.lmu.de

ABSTRACT
Bimanual actions impose intermanual coordination demands not present during unimanual actions. We investigated the functional neuroanatomical correlates of these coordination demands in motor imagery (MI) of everyday actions using functional magnetic resonance imaging (fMRI). For this, 17 participants imagined unimanual actions with the left and right hand as well as bimanual actions while undergoing fMRI. A univariate fMRI analysis showed no reliable cortical activations specific to bimanual MI, indicating that intermanual coordination demands in MI are not associated with increased neural processing. A functional connectivity analysis based on psychophysiological interactions (PPI), however, revealed marked increases in connectivity between parietal and premotor areas within and between hemispheres. We conclude that in MI of everyday actions intermanual coordination demands are primarily met by changes in connectivity between areas and only moderately, if at all, by changes in the amount of neural activity. These results are the first characterization of the neuroanatomical correlates of bimanual coordination demands in MI. Our findings support the assumed equivalence of overt and imagined actions and highlight the differences between uni- and bimanual actions. The findings extent our understanding of the motor system and may aid the development of clinical neurorehabilitation approaches based on mental practice.

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Related in: MedlinePlus

fMRI results.(A) Cortical areas more strongly activated during MI (averaged across all five MI conditions) than during the resting baseline (p(FWE)<.05; T(16)>7.59). Activation peaks of this contrast served as seed regions for the connectivity analysis depicted in panel B. (B) Increased functional connectivity during bimanual MI as compared to unimanual MI. Two seed regions exhibited increased connectivity, the right supramarginal gyrus (red) and the right superior frontal gyrus (green).
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pone-0038506-g002: fMRI results.(A) Cortical areas more strongly activated during MI (averaged across all five MI conditions) than during the resting baseline (p(FWE)<.05; T(16)>7.59). Activation peaks of this contrast served as seed regions for the connectivity analysis depicted in panel B. (B) Increased functional connectivity during bimanual MI as compared to unimanual MI. Two seed regions exhibited increased connectivity, the right supramarginal gyrus (red) and the right superior frontal gyrus (green).

Mentions: The comparison of all Imagery conditions with Baseline revealed a network of activations primarily comprising premotor and parietal areas (Table 1, Fig. 2a). In detail, premotor activation was located in the bilateral supplementary motor area (SMA; BA 6) extending into dorsal premotor cortices of both hemispheres (BA 6), and in the left rolandic operculum extending into the precentral gyrus (BA 6). Parietal activations were evident in the left postcentral gyrus, (BA 1/2), right supramarginal gyrus (BA 40) and bilateral angular (BA39) gyri. These activation peaks (Table 1) served as seed regions for the connectivity analysis (see below).


Neural activation and functional connectivity during motor imagery of bimanual everyday actions.

Szameitat AJ, McNamara A, Shen S, Sterr A - PLoS ONE (2012)

fMRI results.(A) Cortical areas more strongly activated during MI (averaged across all five MI conditions) than during the resting baseline (p(FWE)<.05; T(16)>7.59). Activation peaks of this contrast served as seed regions for the connectivity analysis depicted in panel B. (B) Increased functional connectivity during bimanual MI as compared to unimanual MI. Two seed regions exhibited increased connectivity, the right supramarginal gyrus (red) and the right superior frontal gyrus (green).
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3368848&req=5

pone-0038506-g002: fMRI results.(A) Cortical areas more strongly activated during MI (averaged across all five MI conditions) than during the resting baseline (p(FWE)<.05; T(16)>7.59). Activation peaks of this contrast served as seed regions for the connectivity analysis depicted in panel B. (B) Increased functional connectivity during bimanual MI as compared to unimanual MI. Two seed regions exhibited increased connectivity, the right supramarginal gyrus (red) and the right superior frontal gyrus (green).
Mentions: The comparison of all Imagery conditions with Baseline revealed a network of activations primarily comprising premotor and parietal areas (Table 1, Fig. 2a). In detail, premotor activation was located in the bilateral supplementary motor area (SMA; BA 6) extending into dorsal premotor cortices of both hemispheres (BA 6), and in the left rolandic operculum extending into the precentral gyrus (BA 6). Parietal activations were evident in the left postcentral gyrus, (BA 1/2), right supramarginal gyrus (BA 40) and bilateral angular (BA39) gyri. These activation peaks (Table 1) served as seed regions for the connectivity analysis (see below).

Bottom Line: We conclude that in MI of everyday actions intermanual coordination demands are primarily met by changes in connectivity between areas and only moderately, if at all, by changes in the amount of neural activity.These results are the first characterization of the neuroanatomical correlates of bimanual coordination demands in MI.The findings extent our understanding of the motor system and may aid the development of clinical neurorehabilitation approaches based on mental practice.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology, Ludwig Maximilians University, Munich, Germany. szameitat@psy.lmu.de

ABSTRACT
Bimanual actions impose intermanual coordination demands not present during unimanual actions. We investigated the functional neuroanatomical correlates of these coordination demands in motor imagery (MI) of everyday actions using functional magnetic resonance imaging (fMRI). For this, 17 participants imagined unimanual actions with the left and right hand as well as bimanual actions while undergoing fMRI. A univariate fMRI analysis showed no reliable cortical activations specific to bimanual MI, indicating that intermanual coordination demands in MI are not associated with increased neural processing. A functional connectivity analysis based on psychophysiological interactions (PPI), however, revealed marked increases in connectivity between parietal and premotor areas within and between hemispheres. We conclude that in MI of everyday actions intermanual coordination demands are primarily met by changes in connectivity between areas and only moderately, if at all, by changes in the amount of neural activity. These results are the first characterization of the neuroanatomical correlates of bimanual coordination demands in MI. Our findings support the assumed equivalence of overt and imagined actions and highlight the differences between uni- and bimanual actions. The findings extent our understanding of the motor system and may aid the development of clinical neurorehabilitation approaches based on mental practice.

Show MeSH
Related in: MedlinePlus