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Executive attention networks show altered relationship with default mode network in PD

View Article: PubMed Central - PubMed

ABSTRACT

Attention dysfunction is a common but often undiagnosed cognitive impairment in Parkinson's disease that significantly reduces quality of life. We sought to increase understanding of the mechanisms underlying attention dysfunction using functional neuroimaging. Functional MRI was acquired at two repeated sessions in the resting state and during the Attention Network Test, for 25 non-demented subjects with Parkinson's disease and 21 healthy controls. Behavioral and MRI contrasts were calculated for alerting, orienting, and executive control components of attention. Brain regions showing group differences in attention processing were used as seeds in a functional connectivity analysis of a separate resting state run. Parkinson's disease subjects showed more activation during increased executive challenge in four regions of the dorsal attention and frontoparietal networks, namely right frontal eye field, left and right intraparietal sulcus, and precuneus. In three regions we saw reduced resting state connectivity to the default mode network. Further, whereas higher task activation in the right intraparietal sulcus correlated with reduced resting state connectivity between right intraparietal sulcus and the precuneus in healthy controls, this relationship was absent in Parkinson's disease subjects. Our results suggest that a weakened interaction between the default mode and task positive networks might alter the way in which the executive response is processed in PD.

No MeSH data available.


Related in: MedlinePlus

Group differences in executive task activation. Top row shows regions where the response to incongruent stimuli significantly exceeded the response to congruent stimuli for both groups combined. Bottom row shows regions in red where the executive contrast (incongruent–congruent) was significantly increased in Parkinson's disease. Blue background in bottom row shows regions significantly correlated to the dorsal attention network mask. Left side of image is right side of brain. Column label indicates MNI axial coordinate in mm. lIPS, left intraparietal sulcus; rFEF, right frontal eye field; rIPS, right intraparietal sulcus; rSPL, right superior parietal lobule.
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f0015: Group differences in executive task activation. Top row shows regions where the response to incongruent stimuli significantly exceeded the response to congruent stimuli for both groups combined. Bottom row shows regions in red where the executive contrast (incongruent–congruent) was significantly increased in Parkinson's disease. Blue background in bottom row shows regions significantly correlated to the dorsal attention network mask. Left side of image is right side of brain. Column label indicates MNI axial coordinate in mm. lIPS, left intraparietal sulcus; rFEF, right frontal eye field; rIPS, right intraparietal sulcus; rSPL, right superior parietal lobule.

Mentions: Significant group differences were only found for the executive task, which we focus on for the remainder of the report. Across all subjects the executive contrast shows activation in regions of the dorsal attention network (DAN) and frontoparietal network (FPN), including left frontal eye field (lFEF), right frontal eye field (rFEF), left intraparietal sulcus (lIPS), right intraparietal sulcus (rIPS), right superior precuneus, presupplementary motor area, cerebellum, and left and right lateral ventral occipital cortex (Fig. 3 top). These images show where activation in incongruent trials exceeded activation in congruent trials (z-score > 2.3 SD). There were four clusters where the executive contrast for PD exceeded that for HC (Fig. 3 bottom), namely rFEF, lIPS, rIPS, and right superior parietal lobule (rSPL). Coordinates of maximal activation, size, and significance of these clusters are shown in Table 4. Each executive effect cluster had greater RSN affinity with the DAN and FPN, compared with the DMN or VAN (see Table S1 for affinity to each RSN). In particular, the rSPL cluster lay outside the DMN, with greater rsFC to the DAN or FPN in 82.7% of subjects.


Executive attention networks show altered relationship with default mode network in PD
Group differences in executive task activation. Top row shows regions where the response to incongruent stimuli significantly exceeded the response to congruent stimuli for both groups combined. Bottom row shows regions in red where the executive contrast (incongruent–congruent) was significantly increased in Parkinson's disease. Blue background in bottom row shows regions significantly correlated to the dorsal attention network mask. Left side of image is right side of brain. Column label indicates MNI axial coordinate in mm. lIPS, left intraparietal sulcus; rFEF, right frontal eye field; rIPS, right intraparietal sulcus; rSPL, right superior parietal lobule.
© Copyright Policy - CC BY
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC5121155&req=5

f0015: Group differences in executive task activation. Top row shows regions where the response to incongruent stimuli significantly exceeded the response to congruent stimuli for both groups combined. Bottom row shows regions in red where the executive contrast (incongruent–congruent) was significantly increased in Parkinson's disease. Blue background in bottom row shows regions significantly correlated to the dorsal attention network mask. Left side of image is right side of brain. Column label indicates MNI axial coordinate in mm. lIPS, left intraparietal sulcus; rFEF, right frontal eye field; rIPS, right intraparietal sulcus; rSPL, right superior parietal lobule.
Mentions: Significant group differences were only found for the executive task, which we focus on for the remainder of the report. Across all subjects the executive contrast shows activation in regions of the dorsal attention network (DAN) and frontoparietal network (FPN), including left frontal eye field (lFEF), right frontal eye field (rFEF), left intraparietal sulcus (lIPS), right intraparietal sulcus (rIPS), right superior precuneus, presupplementary motor area, cerebellum, and left and right lateral ventral occipital cortex (Fig. 3 top). These images show where activation in incongruent trials exceeded activation in congruent trials (z-score > 2.3 SD). There were four clusters where the executive contrast for PD exceeded that for HC (Fig. 3 bottom), namely rFEF, lIPS, rIPS, and right superior parietal lobule (rSPL). Coordinates of maximal activation, size, and significance of these clusters are shown in Table 4. Each executive effect cluster had greater RSN affinity with the DAN and FPN, compared with the DMN or VAN (see Table S1 for affinity to each RSN). In particular, the rSPL cluster lay outside the DMN, with greater rsFC to the DAN or FPN in 82.7% of subjects.

View Article: PubMed Central - PubMed

ABSTRACT

Attention dysfunction is a common but often undiagnosed cognitive impairment in Parkinson's disease that significantly reduces quality of life. We sought to increase understanding of the mechanisms underlying attention dysfunction using functional neuroimaging. Functional MRI was acquired at two repeated sessions in the resting state and during the Attention Network Test, for 25 non-demented subjects with Parkinson's disease and 21 healthy controls. Behavioral and MRI contrasts were calculated for alerting, orienting, and executive control components of attention. Brain regions showing group differences in attention processing were used as seeds in a functional connectivity analysis of a separate resting state run. Parkinson's disease subjects showed more activation during increased executive challenge in four regions of the dorsal attention and frontoparietal networks, namely right frontal eye field, left and right intraparietal sulcus, and precuneus. In three regions we saw reduced resting state connectivity to the default mode network. Further, whereas higher task activation in the right intraparietal sulcus correlated with reduced resting state connectivity between right intraparietal sulcus and the precuneus in healthy controls, this relationship was absent in Parkinson's disease subjects. Our results suggest that a weakened interaction between the default mode and task positive networks might alter the way in which the executive response is processed in PD.

No MeSH data available.


Related in: MedlinePlus