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Regional differences of [(18)F]-FDG uptake within the brain during fatiguing muscle contractions.

Kindred JH, Kalliokoski KK, Bojsen-Møller J, Rudroff T - Brain Behav (2015)

Bottom Line: FDG uptake was greater in the occipital and temporal cortices of the brain during the position task compared to the force task.These findings suggest that differences in visual-spatial feedback and processing may play a role in the reduced time to failure of position tasks.Future application of these findings may lead to improved designs of rehabilitative strategies involving different types of visual feedback.

View Article: PubMed Central - PubMed

Affiliation: Department of Health and Exercise Science, Colorado State University Fort Collins, Colorado.

ABSTRACT

Background and purpose: Many studies have shown that a position task is more difficult than a force task although both are performed at a similar net muscle force. Thus, the time to task failure is consistently shown to be briefer during the position task. The contributions of the central nervous system to these two types of fatiguing contractions are not completely understood. The purpose of this pilot study was to examine differences in regional brain activity between force and position tasks using positron emission tomography (PET) with [(18)F]-Fluorodeoxyglucose (FDG).

Methods: Two participants performed both a force and position task, separated by 7 days, with the elbow flexor muscles at 15% maximal voluntary contraction force. During both tasks, each participant was injected with ≈ 256 (SD 11) MBq of FDG. Immediately after both tasks PET imaging was performed and images were analyzed to determine FDG uptake within regions of the brain.

Results: FDG uptake was greater in the occipital and temporal cortices of the brain during the position task compared to the force task.

Conclusions: These findings suggest that differences in visual-spatial feedback and processing may play a role in the reduced time to failure of position tasks. Future application of these findings may lead to improved designs of rehabilitative strategies involving different types of visual feedback.

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Related in: MedlinePlus

Three-dimensional rendering of the brain overlaid with regional differences in cellular activity determined by SPM8, extended threshold k = 250 voxels, P < 0.05. The highest activity differences are denoted in bright yellow, color threshold from 10 to 35 T.
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fig02: Three-dimensional rendering of the brain overlaid with regional differences in cellular activity determined by SPM8, extended threshold k = 250 voxels, P < 0.05. The highest activity differences are denoted in bright yellow, color threshold from 10 to 35 T.

Mentions: MVC values and time to task failure are listed in Table 1. PET image analysis performed within SPM8 revealed several brain regions of increased FDG uptake during the position task image compared to the force task image (Fig.2). These areas include contralateral (right) areas of the occipital, frontal, and temporal cortices. No areas were found to be greater during the force task. Table 2 lists all areas and corresponding P-values.


Regional differences of [(18)F]-FDG uptake within the brain during fatiguing muscle contractions.

Kindred JH, Kalliokoski KK, Bojsen-Møller J, Rudroff T - Brain Behav (2015)

Three-dimensional rendering of the brain overlaid with regional differences in cellular activity determined by SPM8, extended threshold k = 250 voxels, P < 0.05. The highest activity differences are denoted in bright yellow, color threshold from 10 to 35 T.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4356841&req=5

fig02: Three-dimensional rendering of the brain overlaid with regional differences in cellular activity determined by SPM8, extended threshold k = 250 voxels, P < 0.05. The highest activity differences are denoted in bright yellow, color threshold from 10 to 35 T.
Mentions: MVC values and time to task failure are listed in Table 1. PET image analysis performed within SPM8 revealed several brain regions of increased FDG uptake during the position task image compared to the force task image (Fig.2). These areas include contralateral (right) areas of the occipital, frontal, and temporal cortices. No areas were found to be greater during the force task. Table 2 lists all areas and corresponding P-values.

Bottom Line: FDG uptake was greater in the occipital and temporal cortices of the brain during the position task compared to the force task.These findings suggest that differences in visual-spatial feedback and processing may play a role in the reduced time to failure of position tasks.Future application of these findings may lead to improved designs of rehabilitative strategies involving different types of visual feedback.

View Article: PubMed Central - PubMed

Affiliation: Department of Health and Exercise Science, Colorado State University Fort Collins, Colorado.

ABSTRACT

Background and purpose: Many studies have shown that a position task is more difficult than a force task although both are performed at a similar net muscle force. Thus, the time to task failure is consistently shown to be briefer during the position task. The contributions of the central nervous system to these two types of fatiguing contractions are not completely understood. The purpose of this pilot study was to examine differences in regional brain activity between force and position tasks using positron emission tomography (PET) with [(18)F]-Fluorodeoxyglucose (FDG).

Methods: Two participants performed both a force and position task, separated by 7 days, with the elbow flexor muscles at 15% maximal voluntary contraction force. During both tasks, each participant was injected with ≈ 256 (SD 11) MBq of FDG. Immediately after both tasks PET imaging was performed and images were analyzed to determine FDG uptake within regions of the brain.

Results: FDG uptake was greater in the occipital and temporal cortices of the brain during the position task compared to the force task.

Conclusions: These findings suggest that differences in visual-spatial feedback and processing may play a role in the reduced time to failure of position tasks. Future application of these findings may lead to improved designs of rehabilitative strategies involving different types of visual feedback.

Show MeSH
Related in: MedlinePlus