Relationship between Stroop performance and resting state functional connectivity in cognitively normal older adults

Area of Science:

• Neuroscience
• Gerontology
• Medical Imaging

Background:

• Early detection of Alzheimer's disease (AD) is crucial for therapeutic development.
• Attentional control measures, like the Stroop task, differentiate healthy aging from early AD and predict future AD.
• Resting-state functional connectivity MRI (rs-fcMRI) disruptions are observed in AD and at-risk individuals.

Purpose of the Study:

• To investigate the relationship between Stroop task performance, rs-fcMRI, and cerebrospinal fluid (CSF) amyloid-beta 42 (Aβ₄₂) levels.
• To explore potential early AD biomarkers in cognitively normal older adults.

Main Methods:

• 237 cognitively normal older adults underwent a computerized Stroop task, rs-fcMRI, and CSF analysis.
• Compared Stroop performance (including reaction time distributional analyses) with resting-state network (RSN) composite scores (DMN, SAL, DAN, SMN).
• Assessed the influence of CSF Aβ₄₂ levels on these relationships.

Main Results:

• Increased Stroop errors correlated with reduced functional connectivity in the default mode network (DMN) and salience network (SAL).
• Slower reaction times in the tail distribution linked to decreased SAL connectivity.
• Stroop performance-DMN connectivity was stronger in individuals with positive CSF Aβ₄₂ levels.

Conclusions:

• A significant link exists between RSN composite scores and specific attentional performance measures.
• Both rs-fcMRI and Stroop task performance may serve as sensitive biomarkers for early Alzheimer's disease detection.