Longitudinal Study of Spatial Correlations Between Brain Imaging Changes and Atlas-Based Neurotransmitter Maps in...

Emerging evidence in ischemic stroke indicates that imbalances in serotonin and dopamine are linked to motor deficits in stroke survivors. Nevertheless, the spatial relationships between the biological mechanisms underlying stroke and the observed imaging changes remain poorly understood. This study aimed to explore neuroplasticity alterations in chronic subcortical ischemic stroke patients before and after 1-month pharmacological intervention, as well as to assess the spatial connections between the underlying biology and imaging changes. In the present study, all patients underwent two T1-weighted scans and resting-state functional magnetic resonance imaging sessions, spaced 1 month apart. Key assessments focused on gray matter (GM) volume, voxel-mirrored homotopic connectivity (VMHC), and the spatial distribution correlations of neurotransmitters. Longitudinal analysis demonstrated significant reductions in the right precuneus, left calcarine cortex, and left cerebellum, while increases in the left middle cingulate cortex (MCC), left supplementary motor area (SMA), and right precentral gyrus after intervention. Similarly, longitudinal analyses of VMHC showed substantial increases in the inferior parietal lobe, precentral gyrus, middle temporal gyrus, SMA, postcentral gyrus, MCC, and cerebellum. Both neuroimaging metrics in the SMA and precentral gyrus regions exhibited significant correlations with clinical outcomes. Additionally, a notable connection was observed between neuroimaging measures (GM volume and VMHC) and the spatial distribution of neurotransmitter systems, including serotonergic systems and vesicular acetylcholine transporter. Taken together, these results highlight the evolving neuroimaging changes that occur after an ischemic stroke and provide novel insights into the underlying neurological processes driving these longitudinal alterations in stroke patients.