Connectivity in response to All Positive Feedback in MS participants
fatigue
EVENTS, MULTIPLE SCLEROSIS, POSITIVE
gPPI results revealed no significant changes in either VS or caudate connectivity during All Positive vs. All Negative Feedback within either group.When examining All Positive Feedback separately, we observed a group difference, such that the VS displayed stronger connections with the left angular gyrus (AG) and right superior temporal gyrus (STG) in the MS group (Functional connectivity results. A) gPPI results revealed stronger connectivity between the VS (yellow circles, top panel), left AG (left panel), and right STG (right panel) in the MS group, compared to the NT group, during All Positive Feedback. B) Relative to NT participants, MS participants displayed potential reductions in connectivity between the caudate (green circles) and right dACC, in response to state fatigue experienced during All Positive Feedback, though the cluster size associated with this effect does not survive multiple comparison correction. C) Results also revealed stronger connectivity between the caudate (green circles) and left precentral gyrus within MS participants during All Positive Feedback. A cluster-defining threshold of gPPI Analysis Activation Clusters and Local Maxima for Primary Feedback Contrasts.Peak intensities within each cluster with z values exceeding the cluster-defining threshold of 3.1 (p <.001, cluster-corrected to p <.013) for each event/contrast of events. Each unique cluster identified within the event/contrast is numerically listed in the “Cluster Number” column. When multiple peaks were identified within the same region, the reported coordinates correspond to peak activation with the highest z value. The Harvard-Oxford and Montreal Neurological Institute (MNI) Structural Atlases were used for the identification of anatomical brain region labels. MS = multiple sclerosis, NT = neurotypical, L = left hemisphere, R = right hemisphere.During All Positive Feedback, a group interaction emerged, whereby the MS group displayed a reduction in connectivity between the caudate and right dACC that was associated with greater state fatigue, while the NT group displayed increased caudate-dACC connectivity associated with greater state fatigue (With respect to within-group connectivity, the MS group displayed enhanced connections between the caudate and left precentral gyrus and left middle frontal gyrus (We did not observe any significant associations between any of these connectivity patterns and learning between Phase 2 and Phase 3 (i.e., delta performance). However, within the MS group, a non-significant trending association emerged between strengthened VS-STG connectivity and better learning: 