A Data-Driven Investigation of Gray Matter-Function Correlations in Schizophrenia during a Working Memory Task.

Area of Science:

• Neuroscience
• Brain Imaging
• Cognitive Neuroscience

Background:

• Schizophrenia is linked to distributed brain region disconnection.
• Investigating long-range structure-function (S-F) associations is crucial for understanding schizophrenia.
• Previous work reduced S-F correlations to histograms; this study refines this to brain clusters.

Purpose of the Study:

• To apply a novel methodology for reducing whole-brain S-F correlations to brain clusters.
• To investigate S-F associations in schizophrenia (SZ) patients versus healthy controls (HC) using structural MRI and fMRI data.
• To identify how S-F differential correlations change across memory load levels during working memory tasks.

Main Methods:

• Utilized structural MRI (gray matter concentration) and fMRI (activation maps) data from 100 SZ patients and 100 HC.
• Reduced whole-brain S-F correlations to brain clusters.
• Computed differential correlation clusters using activation data for the 'Probe Medium' condition.

Main Results:

• Healthy controls showed overlapping S-F correlation histograms for low/medium memory loads, separating at high loads; schizophrenia patients showed no overlap across all loads.
• Differential correlation clusters included superior temporal gyri, anterior cingulate, cuneus, middle temporal gyrus, and cerebellum.
• Inter-cluster correlations were positive in HC but negative in SZ for 'Probe Medium' load, indicating aberrant S-F integrity in SZ.

Conclusions:

• The study identified novel brain clusters and demonstrated changes in S-F differential correlation during working memory tasks at varying loads.
• Findings suggest that evaluating S-F associations provides critical information for understanding schizophrenia.
• Aberrant S-F integrity during memory tasks is evident in schizophrenia patients.