[Altered Functional Connectivity in Patients with Transient Ischemic Attack by Resting-state Functional MRI]

Area of Science:

• Neuroscience
• Neurology
• Medical Imaging

Background:

• Transient ischemic attack (TIA) can lead to subtle, long-term neurological changes.
• Understanding functional connectivity alterations is crucial for TIA patient recovery.
• Resting-state functional magnetic resonance imaging (fMRI) offers insights into brain network dynamics.

Purpose of the Study:

• To investigate longitudinal changes in resting-state functional connectivity in patients following a first-time TIA.
• To compare functional connectivity patterns between TIA patients and healthy controls over time.
• To explore the relationship between functional connectivity and cognitive performance post-TIA.

Main Methods:

• Recruited 35 first-time TIA patients (right hemisphere) and 35 healthy controls.
• Performed fMRI scans at 1 week and 3 months post-TIA.
• Assessed resting-state functional connectivity using the right inferior prefrontal cortex (iPFC) as the region of interest (ROI).

Main Results:

• At 1 week post-TIA, patients showed increased connectivity with the cerebellum and insula, and decreased connectivity with the middle frontal gyrus (MFG) compared to controls.
• At 3 months post-TIA, patients exhibited decreased connectivity in the superior temporal gyrus (STG), insula, and thalamus.
• Functional connectivity between the right iPFC, cerebellum, and insula correlated with working memory performance (2-back reaction time) at 1 week post-TIA.

Conclusions:

• TIA patients experience persistent alterations in brain functional connectivity, particularly in working memory-related regions.
• While acute neurological symptoms may resolve, underlying network dysfunction can endure.
• These findings highlight the importance of long-term monitoring and potential interventions for TIA survivors.