Frequency-dependent activity decreases of DMN associate with depression and cognition in patients with postacute sequelae of SARS-CoV-2

Motivation: Patients with postacute sequelae of SARS-CoV-2 infection (PASC) present chronic symptoms. However, the underlying neurological basis remains to be investigated. Goal(s): Investigating alterations of brain activity and the correlation with clinic symptoms in PASC patients. Approach: 29 PASC, 27 non-PASC, and 31 health controls were involved. Intrinsic brain activity was assessed using fractional-amplitude of low-frequency fluctuation (fALFF) of resting-state fMRI. The fALFF in typical frequency band (0.01-0.10Hz) as well as slow-band 4 (0.023-0.073 Hz) and slow-band 5 (0.01-0.023Hz) were analyzed. Results: The alterations of different band fALFF in the default mode network were significantly associated with cognitive and depressive symptoms in PASC patients. Impact: Our findings may reshape the understanding of neurological consequences of COVID-19. It would be helpful for guiding future studies on therapeutic interventions and enhancing diagnostic criteria for PASC.