biostudies-literatureCamargo ANational Center for Advancing Translational SciencesNational Institute of Neurological Disorders and StrokeNIBIB NIH HHSNCATS NIH HHSNIA NIH HHSNIMH NIH HHSNINDS NIH HHSNational Institute on AgingNational Institute of Biomedical Imaging and Bioengineeringe25310https://www.ebi.ac.uk/biostudies/studies/S-EPMC10947426biostudies-literatureUnknown102(2)Entropy indicates irregularity of a dynamic system, with higher entropy indicating higher irregularity and more transit states. In the human brain, regional brain entropy (BEN) has been increasingly assessed using resting state fMRI (rs-fMRI), while changes of regional BEN during task-based fMRI have been scarcely studied. The purpose of this study is to characterize task-induced regional BEN alterations using the large Human Connectome Project (HCP) data. To control the potential modulation by the block design, BEN of task-fMRI was calculated from the fMRI images acquired during the task conditions only (task BEN) and then compared to BEN of rs-fMRI (resting BEN). Moreover, BEN was separately calculated from the control blocks of the task-fMRI runs (control BEN) and compared to task BEN. Finally, control BEN was compared to resting BEN to test for residual task effects in the control condition. With respect to resting state, task performance unanimously induced BEN reduction in the peripheral cortical area and BEN increase in the centric part of the sensorimotor and perception networks. Control compared to resting BEN showed similar entropy alterations, suggesting large residual task effects. Task compared to control BEN was characterized by reduced entropy in occipital, orbitofrontal, and parietal regions.Journal of neuroscience researchTask-induced changes in brain entropy.PMC10947426R01AG060054P41 EB029460UL1 TR003098R01EB031080‐01A1P41EB029460-01A1R01AG070227P41EB029460‐01A1R01EB031080-01A1R21AG082345R01 AG070227R21 AG082345R01 AG060054R01 EB031080U54 MH091657Camargo ADel Mauro GWang ZfalseTask-induced changes in brain entropy.Entropy indicates irregularity of a dynamic system, with higher entropy indicating higher irregularity and more transit states. In the human brain, regional brain entropy (BEN) has been increasingly assessed using resting state fMRI (rs-fMRI), while changes of regional BEN during task-based fMRI have been scarcely studied. The purpose of this study is to characterize task-induced regional BEN alterations using the large Human Connectome Project (HCP) data. To control the potential modulation by the block design, BEN of task-fMRI was calculated from the fMRI images acquired during the task conditions only (task BEN) and then compared to BEN of rs-fMRI (resting BEN). Moreover, BEN was separately calculated from the control blocks of the task-fMRI runs (control BEN) and compared to task BEN. Finally, control BEN was compared to resting BEN to test for residual task effects in the control condition. With respect to resting state, task performance unanimously induced BEN reduction in the peripheral cortical area and BEN increase in the centric part of the sensorimotor and perception networks. Control compared to resting BEN showed similar entropy alterations, suggesting large residual task effects. Task compared to control BEN was characterized by reduced entropy in occipital, orbitofrontal, and parietal regions.2024-01-01T00:00:00Z2024 Feb2025-04-03T23:22:36.338Z2025-04-03T23:22:36.338ZS-EPMC109474263840055310.1002/jnr.25310