Altered Structure and Intrinsic Functional Connectivity in Post-stroke Aphasia

Area of Science:

• Neuroscience
• Neurology
• Radiology

Background:

• Previous research indicates gray matter alterations in post-stroke aphasia (PSA).
• Few studies have integrated gray matter volume (GMV) and intrinsic functional connectivity (iFC) analysis in PSA.
• Understanding the neurobiological underpinnings of PSA is crucial for effective treatment.

Purpose of the Study:

• To investigate structural GMV abnormalities in PSA patients using voxel-based morphometry.
• To examine the relationship between GMV alterations and iFC imbalances in PSA.
• To explore correlations between altered iFC and clinical scores in patients with aphasia.

Main Methods:

• Voxel-based morphometry (VBM) was used to assess GMV differences between PSA patients (n=17) and healthy controls (HCs, n=20).
• Resting-state functional MRI was employed to evaluate intrinsic functional connectivity (iFC).
• Correlations between iFC and clinical aphasia scores were analyzed.

Main Results:

• PSA patients exhibited increased GMV in the right superior temporal gyrus, right inferior parietal lobule/supramarginal gyrus, and left middle occipital gyrus.
• Decreased GMV was observed in the right caudate nucleus and bilateral thalami in PSA patients.
• Altered iFC patterns included increased connectivity between the right IPL/SMG and other regions, and reduced connectivity in the right caudate and frontal areas. iFC between the left middle occipital gyrus and left orbital middle frontal gyrus correlated with performance quotient.

Conclusions:

• GMV abnormalities in PSA are associated with altered interregional functional connectivity.
• These findings suggest a link between structural brain changes and functional network disruptions in post-stroke aphasia.
• The study provides valuable insights into the pathogenesis of PSA and may inform future therapeutic strategies.