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

Area of Science:

• Neuroscience
• Cognitive Neurology
• Neuroimaging

Background:

• Attention dysfunction is a prevalent, often overlooked cognitive deficit in Parkinson's disease (PD).
• This impairment significantly diminishes patients' quality of life.
• Understanding the neural mechanisms of attention deficits in PD is crucial for developing targeted interventions.

Purpose of the Study:

• To investigate the neurobiological underpinnings of attention dysfunction in Parkinson's disease.
• To explore differences in brain activation and functional connectivity during attention tasks between PD patients and healthy controls.

Main Methods:

• Functional magnetic resonance imaging (fMRI) was employed in 25 non-demented PD subjects and 21 healthy controls.
• Scans were conducted during resting state and the Attention Network Test (ANT) across two sessions.
• Functional connectivity analysis utilized resting-state data, with brain regions identified from ANT contrasts as seeds.

Main Results:

• Parkinson's disease subjects exhibited heightened activation in the dorsal attention and frontoparietal networks (right frontal eye field, bilateral intraparietal sulcus, precuneus) under executive load.
• Reduced resting-state functional connectivity between these task-positive regions and the default mode network was observed in PD.
• The correlation between task activation in the right intraparietal sulcus and resting-state connectivity with the precuneus, present in controls, was absent in PD.

Conclusions:

• Parkinson's disease is associated with altered functional brain network dynamics during attention processing.
• Weakened interactions between the default mode network and task-positive networks may underlie executive response alterations in PD.
• These findings highlight potential neuroimaging biomarkers for attention deficits in Parkinson's disease.