Aberrant functional connectivity of resting state networks in transient ischemic attack

Area of Science:

• Neuroscience
• Radiology
• Neurology

Background:

• Transient ischemic attack (TIA) is a neurological disorder typically without permanent cerebral infarction.
• However, TIA patients can experience lasting cognitive impairments.
• Resting state networks (RSNs) represent the brain's intrinsic functional architecture.

Purpose of the Study:

• To identify differences in resting state networks (RSNs) between TIA patients and healthy controls (HCs).

Main Methods:

• Functional magnetic resonance imaging (fMRI) and independent component analysis (ICA) were used to analyze RSNs.
• Cognitive and psychiatric tests were administered to 21 TIA patients and 21 matched HCs.
• Statistical analysis compared RSN functional connectivity (FC) between groups and correlated FC with clinical scores.

Main Results:

• TIA patients displayed altered functional connectivity in all eight analyzed RSNs compared to HCs.
• Specific networks like the default mode network (DMN) and self-referential network (SRN) showed both decreased and increased FC.
• Other networks, including dorsal attention (DAN), central-executive (CEN), and somato-motor (SMN), showed decreased FC.

Conclusions:

• TIA is associated with widespread intrinsic functional connectivity impairments across all major brain networks.
• These findings suggest TIA impacts the brain's functional architecture more broadly than previously understood.
• Aberrant RSNs in TIA patients may offer new insights into neuro-pathophysiological mechanisms.