Brain structure & function
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Deep brain stimulation (DBS) is effective in managing motor symptoms of Parkinson's disease in well-selected individuals. Recently, research has shown that DBS in the basal ganglia (BG) can alter neural circuits beyond the traditional basal ganglia-thalamus-cortical (BG-TH-CX) loop. For instance, functional imaging showed alterations in cerebellar activity with DBS in the subthalamic nucleus (STN). ⋯ Then, we applied STN-DBS at sub-therapeutic current along with stimulation of the deep cerebellar nuclei and found similar improvement in forelimb akinesia as with therapeutic STN-DBS alone. This suggests that STN-DBS can engage cerebellar activity to improve parkinsonian motor symptoms. Our study is the first to describe how STN-DBS in Parkinson's disease alters cerebellar activity using electrophysiology in vivo and reveal a potential for stimulating the cerebellum to potentiate deep brain stimulation of the subthalamic nucleus.
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To evaluate brain development longitudinally in premature infants without abnormalities as compared to healthy full-term newborns, we assessed fMRI brain activity patterns in response to linguistic stimuli and white matter structural development focusing on language-related fibres. A total sample of 29 preterm newborns and 26 at term control newborns underwent both fMRI and DTI. Griffiths test was performed at 6 months of corrected age to assess development. ⋯ The different pattern of brain activity associated to preterm newborns mirrors their white matter maturation delay in peripheral regions of the fibres and thalamo-cortical radiations in subcortical areas of both hemispheres, pointing to different transient thalamo-cortical development due to prematurity. Evidence for functional thalamic activation and more mature subcortical tracts, including thalamic radiations, may represent the substantial gap between preterm and at term infants. The transition between bilateral temporal activations at term age and leftward activations at 44 weeks of PMA is correlated to better neuropsychological results in Griffiths test.