Altered Global Signal Topography in Schizophrenia

Area of Science:

• Neuroscience
• Psychiatry
• Medical Imaging

Background:

• Schizophrenia (SCZ) is a severe neuropsychiatric disorder linked to widespread neural system disruptions.
• Resting-state fMRI reveals blood-oxygen-level-dependent signal abnormalities in SCZ, including changes in the global signal (GS).
• The spatial distribution of these global signal alterations in SCZ remains unclear.

Purpose of the Study:

• To quantify the network-by-network topography of the global signal in healthy individuals and SCZ patients.
• To investigate whether global signal alterations in SCZ are pervasive or spatially specific.

Main Methods:

• Utilized resting-state functional magnetic resonance imaging (fMRI).
• Performed network-by-network quantification of the global signal (GS) topography.
• Compared GS patterns between healthy subjects and SCZ patients.

Main Results:

• Healthy subjects displayed a nonuniform GS topography, with sensory areas showing the largest GS component.
• SCZ patients exhibited preferential increases in GS representation in association regions.
• Sensory regions showed preferential GS reductions in SCZ patients, and the anti-correlation between sensory and association GS was reduced.

Conclusions:

• Global signal topography is nonuniform in healthy brains, with a distinct pattern in SCZ.
• Shifts in GS topography in SCZ may indicate profound alterations in neural information flow.
• Findings may inform the development of novel pharmacotherapies for schizophrenia.