Functional brain abnormalities in post COVID-19 condition and their relationship with cognition

Area of Science:

• Neuroscience
• Medical Imaging
• Cognitive Science

Background:

• Post-COVID condition (PCC), or long COVID, frequently involves persistent cognitive dysfunction.
• Altered brain functional connectivity (FC) is a suspected underlying mechanism, but its specific network characteristics and clinical correlations in PCC are not well understood.

Purpose of the Study:

• To investigate intra- and inter-network functional connectivity (FC) differences in individuals with PCC compared to healthy controls.
• To examine the relationship between altered FC, cognitive status, and clinical outcomes in PCC patients.

Main Methods:

• Recruited 121 PCC patients (with/without cognitive impairment) and 37 healthy controls.
• Utilized resting-state functional magnetic resonance imaging (fMRI) and comprehensive neuropsychological assessments.
• Analyzed resting-state networks using independent component analysis, dual regression, and network modeling for FC characterization.

Main Results:

• PCC patients exhibited increased intra-network FC in 10 cognitive networks, including default mode and executive control networks.
• Increased FC positively correlated with general cognition (MoCA scores), time since infection, fatigue, and subjective memory issues.
• Elevated inter-network FC was observed between default mode and sensorimotor networks.

Conclusions:

• Increased functional connectivity (FC) in PCC may represent an inefficient compensatory mechanism.
• These FC alterations are associated with key PCC symptoms such as fatigue and subjective memory complaints.
• Findings highlight the link between brain network dysfunction and the persistence of post-COVID cognitive deficits.