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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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Trial design.
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pone-0038506-g003: Trial design.

Mentions: The paradigm comprised five conditions, Biman, Simple-L, Simple-R, Complex-L, Complex-R, and Baseline. Except for Baseline, each condition was repeated seven times. The experiment used a block design consisting of 35 one-minute cycles. Each cycle embodied an instruction and preparation period (12 s), an imagination period (24 s), and a resting baseline period (Baseline, 24 s) (Figure 3). To optimize BOLD signal recovery the unimanual imagery conditions were presented in two basic patterns alternating hand and complexity, i.e.: Simple-L, Complex-R, Simple-L, Complex-R, and so forth and Simple-R, Complex-L, Simple-R, Complex-L, and so forth. The randomization pattern was switched after every Biman condition, which was presented randomly every third to fifth cycle. The experiment was split in two runs of 18 min (18 cycles) and 17 min (17 cycles) respectively.


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

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

Trial design.
© Copyright Policy
Related In: Results  -  Collection

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

pone-0038506-g003: Trial design.
Mentions: The paradigm comprised five conditions, Biman, Simple-L, Simple-R, Complex-L, Complex-R, and Baseline. Except for Baseline, each condition was repeated seven times. The experiment used a block design consisting of 35 one-minute cycles. Each cycle embodied an instruction and preparation period (12 s), an imagination period (24 s), and a resting baseline period (Baseline, 24 s) (Figure 3). To optimize BOLD signal recovery the unimanual imagery conditions were presented in two basic patterns alternating hand and complexity, i.e.: Simple-L, Complex-R, Simple-L, Complex-R, and so forth and Simple-R, Complex-L, Simple-R, Complex-L, and so forth. The randomization pattern was switched after every Biman condition, which was presented randomly every third to fifth cycle. The experiment was split in two runs of 18 min (18 cycles) and 17 min (17 cycles) respectively.

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