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Preliminary fMRI findings in experimentally sleep-restricted adolescents engaged in a working memory task.

Beebe DW, Difrancesco MW, Tlustos SJ, McNally KA, Holland SK - Behav Brain Funct (2009)

Bottom Line: Our data suggest that, when asked to maintain attention and burdened by chronic sleep restriction, the adolescent brain responds via compensatory mechanisms that accentuate the typical activation patterns of attention-relevant brain regions.Specifically, it appeared that regions that are normally active during an attention-demanding working memory task in the well-rested brain became even more active to maintain performance after chronic sleep restriction.Although limited by the small sample, study results provide important evidence of feasibility, as well as guidance for future research into the functional neurological effects of chronic sleep restriction in general, the effects of sleep restriction in children and adolescents, and the neuroscience of attention and its disorders in children.

View Article: PubMed Central - HTML - PubMed

Affiliation: Division of Behavioral Medicine and Clinical Psychology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, Ohio, USA. dean.beebe@cchmc.org.

ABSTRACT
Here we report preliminary findings from a small-sample functional magnetic resonance imaging (fMRI) study of healthy adolescents who completed a working memory task in the context of a chronic sleep restriction experiment. Findings were consistent with those previously obtained on acutely sleep-deprived adults. Our data suggest that, when asked to maintain attention and burdened by chronic sleep restriction, the adolescent brain responds via compensatory mechanisms that accentuate the typical activation patterns of attention-relevant brain regions. Specifically, it appeared that regions that are normally active during an attention-demanding working memory task in the well-rested brain became even more active to maintain performance after chronic sleep restriction. In contrast, regions in which activity is normally suppressed during such a task in the well-rested brain showed even greater suppression to maintain performance after chronic sleep restriction. Although limited by the small sample, study results provide important evidence of feasibility, as well as guidance for future research into the functional neurological effects of chronic sleep restriction in general, the effects of sleep restriction in children and adolescents, and the neuroscience of attention and its disorders in children.

No MeSH data available.


Related in: MedlinePlus

Accuracy and reaction time were comparable across sleep conditions on the 0-back and 2-back tasks (p > .10). SR = Sleep Restriction, HD = Healthy Sleep Duration.
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Figure 1: Accuracy and reaction time were comparable across sleep conditions on the 0-back and 2-back tasks (p > .10). SR = Sleep Restriction, HD = Healthy Sleep Duration.

Mentions: N-back performance was comparable across the two experimental conditions (Figure 1). Consistent with prior studies (e.g., [18,19]), in both conditions the 2-back task resulted in relative activation in task positive regions and deactivation in task negative regions. These are graphically illustrated in Figure 2 and indexed in Tables 2 and 3 by conventional label, Brodmann's area [27] and Talairach coordinates to serve as a baseline reference. Though the activation patterns were similar across conditions, the intensity of such activation/deactivation differed across conditions. Relative to HD, in the SR condition subjects showed greater activation in the task positive ROI and more deactivation in the task negative ROI (Figure 3). The estimated sampling distributions did not overlap across conditions, suggesting that the mean differences were not due to sampling error.


Preliminary fMRI findings in experimentally sleep-restricted adolescents engaged in a working memory task.

Beebe DW, Difrancesco MW, Tlustos SJ, McNally KA, Holland SK - Behav Brain Funct (2009)

Accuracy and reaction time were comparable across sleep conditions on the 0-back and 2-back tasks (p > .10). SR = Sleep Restriction, HD = Healthy Sleep Duration.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2654567&req=5

Figure 1: Accuracy and reaction time were comparable across sleep conditions on the 0-back and 2-back tasks (p > .10). SR = Sleep Restriction, HD = Healthy Sleep Duration.
Mentions: N-back performance was comparable across the two experimental conditions (Figure 1). Consistent with prior studies (e.g., [18,19]), in both conditions the 2-back task resulted in relative activation in task positive regions and deactivation in task negative regions. These are graphically illustrated in Figure 2 and indexed in Tables 2 and 3 by conventional label, Brodmann's area [27] and Talairach coordinates to serve as a baseline reference. Though the activation patterns were similar across conditions, the intensity of such activation/deactivation differed across conditions. Relative to HD, in the SR condition subjects showed greater activation in the task positive ROI and more deactivation in the task negative ROI (Figure 3). The estimated sampling distributions did not overlap across conditions, suggesting that the mean differences were not due to sampling error.

Bottom Line: Our data suggest that, when asked to maintain attention and burdened by chronic sleep restriction, the adolescent brain responds via compensatory mechanisms that accentuate the typical activation patterns of attention-relevant brain regions.Specifically, it appeared that regions that are normally active during an attention-demanding working memory task in the well-rested brain became even more active to maintain performance after chronic sleep restriction.Although limited by the small sample, study results provide important evidence of feasibility, as well as guidance for future research into the functional neurological effects of chronic sleep restriction in general, the effects of sleep restriction in children and adolescents, and the neuroscience of attention and its disorders in children.

View Article: PubMed Central - HTML - PubMed

Affiliation: Division of Behavioral Medicine and Clinical Psychology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, Ohio, USA. dean.beebe@cchmc.org.

ABSTRACT
Here we report preliminary findings from a small-sample functional magnetic resonance imaging (fMRI) study of healthy adolescents who completed a working memory task in the context of a chronic sleep restriction experiment. Findings were consistent with those previously obtained on acutely sleep-deprived adults. Our data suggest that, when asked to maintain attention and burdened by chronic sleep restriction, the adolescent brain responds via compensatory mechanisms that accentuate the typical activation patterns of attention-relevant brain regions. Specifically, it appeared that regions that are normally active during an attention-demanding working memory task in the well-rested brain became even more active to maintain performance after chronic sleep restriction. In contrast, regions in which activity is normally suppressed during such a task in the well-rested brain showed even greater suppression to maintain performance after chronic sleep restriction. Although limited by the small sample, study results provide important evidence of feasibility, as well as guidance for future research into the functional neurological effects of chronic sleep restriction in general, the effects of sleep restriction in children and adolescents, and the neuroscience of attention and its disorders in children.

No MeSH data available.


Related in: MedlinePlus