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Attentional set-shifting deficit in Parkinson's disease is associated with prefrontal dysfunction: an FDG-PET study.

Sawada Y, Nishio Y, Suzuki K, Hirayama K, Takeda A, Hosokai Y, Ishioka T, Itoyama Y, Takahashi S, Fukuda H, Mori E - PLoS ONE (2012)

Bottom Line: Although several neuroimaging studies have addressed this issue, the results of these studies were confounded by the use of tasks that required other cognitive processes in addition to set-shifting, such as rule learning and working memory.Shift cost, which is a measure of attentional set-shifting ability, was significantly correlated with hypometabolism in the right dorsolateral prefrontal cortex, including the putative human frontal eye field.Our results provide direct evidence that dysfunction in the dorsolateral prefrontal cortex makes a primary contribution to the attentional set-shifting deficit that has been observed in PD patients.

View Article: PubMed Central - PubMed

Affiliation: Department of Behavioral Neurology and Cognitive Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Japan.

ABSTRACT
The attentional set-shifting deficit that has been observed in Parkinson's disease (PD) has long been considered neuropsychological evidence of the involvement of meso-prefrontal and prefrontal-striatal circuits in cognitive flexibility. However, recent studies have suggested that non-dopaminergic, posterior cortical pathologies may also contribute to this deficit. Although several neuroimaging studies have addressed this issue, the results of these studies were confounded by the use of tasks that required other cognitive processes in addition to set-shifting, such as rule learning and working memory. In this study, we attempted to identify the neural correlates of the attentional set-shifting deficit in PD using a compound letter task and 18F-fluoro-deoxy-glucose (FDG) positron emission tomography during rest. Shift cost, which is a measure of attentional set-shifting ability, was significantly correlated with hypometabolism in the right dorsolateral prefrontal cortex, including the putative human frontal eye field. Our results provide direct evidence that dysfunction in the dorsolateral prefrontal cortex makes a primary contribution to the attentional set-shifting deficit that has been observed in PD patients.

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Related in: MedlinePlus

Mean RTs and error rates in the psychophysical tasks.Comparisons that were significantly different are indicated with a * (p<0.05/3). There was a significant simple interaction between group and the Global/Mixed task factor (F = 5.99, p = 0.016), and there was a trend toward an interaction between the group and the Local/Mixed task factor (F = 5.63, p = 0.020). PD, Parkinson’s disease.
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pone-0038498-g002: Mean RTs and error rates in the psychophysical tasks.Comparisons that were significantly different are indicated with a * (p<0.05/3). There was a significant simple interaction between group and the Global/Mixed task factor (F = 5.99, p = 0.016), and there was a trend toward an interaction between the group and the Local/Mixed task factor (F = 5.63, p = 0.020). PD, Parkinson’s disease.

Mentions: A two-way repeated-measures ANOVA that used task (Global, Local, and Mixed) and group (PD and control) as factors revealed significant effects of both group (F = 7.06, p = 0.016) and task (F = 43.33, p = 0.001) and a significant interaction between the two factors (F = 5.00, p = 0.001) (Figure 2). The post hoc group comparisons for the three individual tasks (significance level p<0.05/3) showed that compared to the controls, the PD patients had significantly longer mean RTs in both the Global and Mixed tasks (Global, p = 0.004; Mixed, p = 0.001). There was also a trend toward longer mean RTs in the Local task in the PD group compared to the control group (p = 0.093). The between-task comparisons for each group (at a significance level of p<0.05/3) revealed that the mean RTs were significantly longer for the Mixed task than for either the Global or the Local task in both the PD and control groups (Global vs. Mixed, p = 0.001; Local vs. Mixed, p = 0.001 in both groups). No significant differences between the Global and Local tasks were identified in either group (p = 0.118 in the PD group, p = 0.260 in the control group). In addition, we found a significant interaction (significance level p<0.05/3) between the Mixed and Global tasks (F = 5.99, p = 0.016) and a trend between the Mixed and Local tasks (F = 5.63, p = 0.020). There was no significant interaction between the Global and Local tasks (F = 5.63, p = 0.209). In summary, the RTs for the Mixed task were disproportionately longer than for either the Global task or the Local task in the PD patients compared to control participants (Figure 2).


Attentional set-shifting deficit in Parkinson's disease is associated with prefrontal dysfunction: an FDG-PET study.

Sawada Y, Nishio Y, Suzuki K, Hirayama K, Takeda A, Hosokai Y, Ishioka T, Itoyama Y, Takahashi S, Fukuda H, Mori E - PLoS ONE (2012)

Mean RTs and error rates in the psychophysical tasks.Comparisons that were significantly different are indicated with a * (p<0.05/3). There was a significant simple interaction between group and the Global/Mixed task factor (F = 5.99, p = 0.016), and there was a trend toward an interaction between the group and the Local/Mixed task factor (F = 5.63, p = 0.020). PD, Parkinson’s disease.
© Copyright Policy
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC3369918&req=5

pone-0038498-g002: Mean RTs and error rates in the psychophysical tasks.Comparisons that were significantly different are indicated with a * (p<0.05/3). There was a significant simple interaction between group and the Global/Mixed task factor (F = 5.99, p = 0.016), and there was a trend toward an interaction between the group and the Local/Mixed task factor (F = 5.63, p = 0.020). PD, Parkinson’s disease.
Mentions: A two-way repeated-measures ANOVA that used task (Global, Local, and Mixed) and group (PD and control) as factors revealed significant effects of both group (F = 7.06, p = 0.016) and task (F = 43.33, p = 0.001) and a significant interaction between the two factors (F = 5.00, p = 0.001) (Figure 2). The post hoc group comparisons for the three individual tasks (significance level p<0.05/3) showed that compared to the controls, the PD patients had significantly longer mean RTs in both the Global and Mixed tasks (Global, p = 0.004; Mixed, p = 0.001). There was also a trend toward longer mean RTs in the Local task in the PD group compared to the control group (p = 0.093). The between-task comparisons for each group (at a significance level of p<0.05/3) revealed that the mean RTs were significantly longer for the Mixed task than for either the Global or the Local task in both the PD and control groups (Global vs. Mixed, p = 0.001; Local vs. Mixed, p = 0.001 in both groups). No significant differences between the Global and Local tasks were identified in either group (p = 0.118 in the PD group, p = 0.260 in the control group). In addition, we found a significant interaction (significance level p<0.05/3) between the Mixed and Global tasks (F = 5.99, p = 0.016) and a trend between the Mixed and Local tasks (F = 5.63, p = 0.020). There was no significant interaction between the Global and Local tasks (F = 5.63, p = 0.209). In summary, the RTs for the Mixed task were disproportionately longer than for either the Global task or the Local task in the PD patients compared to control participants (Figure 2).

Bottom Line: Although several neuroimaging studies have addressed this issue, the results of these studies were confounded by the use of tasks that required other cognitive processes in addition to set-shifting, such as rule learning and working memory.Shift cost, which is a measure of attentional set-shifting ability, was significantly correlated with hypometabolism in the right dorsolateral prefrontal cortex, including the putative human frontal eye field.Our results provide direct evidence that dysfunction in the dorsolateral prefrontal cortex makes a primary contribution to the attentional set-shifting deficit that has been observed in PD patients.

View Article: PubMed Central - PubMed

Affiliation: Department of Behavioral Neurology and Cognitive Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Japan.

ABSTRACT
The attentional set-shifting deficit that has been observed in Parkinson's disease (PD) has long been considered neuropsychological evidence of the involvement of meso-prefrontal and prefrontal-striatal circuits in cognitive flexibility. However, recent studies have suggested that non-dopaminergic, posterior cortical pathologies may also contribute to this deficit. Although several neuroimaging studies have addressed this issue, the results of these studies were confounded by the use of tasks that required other cognitive processes in addition to set-shifting, such as rule learning and working memory. In this study, we attempted to identify the neural correlates of the attentional set-shifting deficit in PD using a compound letter task and 18F-fluoro-deoxy-glucose (FDG) positron emission tomography during rest. Shift cost, which is a measure of attentional set-shifting ability, was significantly correlated with hypometabolism in the right dorsolateral prefrontal cortex, including the putative human frontal eye field. Our results provide direct evidence that dysfunction in the dorsolateral prefrontal cortex makes a primary contribution to the attentional set-shifting deficit that has been observed in PD patients.

Show MeSH
Related in: MedlinePlus