NeuroImage. Clinical
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NeuroImage. Clinical · Jan 2020
Amygdala response to emotional faces in adolescents with persistent post-concussion symptoms.
Approximately 30% of adolescents with concussion develop persistent post-concussion symptoms (PPCS) that include emotional symptoms. Elevated amygdalae reactivity to emotional faces has been reported in a variety of psychopathologies characterized by emotional symptoms overlapping with those in PPCS. We tested the hypothesis that amygdalae reactivity to emotional faces in adolescents with PPCS+ is elevated compared to concussed adolescents without PPCS and healthy controls. ⋯ Contrary to our hypothesis, PPCS+ had lower amygdalae activity to the emotional faces versus shapes condition relative to HC and a trend for lower activity relative to PPCS-. There was a non-significant inverse association between anhedonia amygdalae activity in adolescents with PPCS. Results suggest that adolescents with PPCS have altered amygdalae activity during the processing of emotional face stimuli.
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NeuroImage. Clinical · Jan 2020
Imaging the Nigrosome 1 in the substantia nigra using susceptibility weighted imaging and quantitative susceptibility mapping: An application to Parkinson's disease.
Parkinson's disease (PD) is a clinically heterogeneous chronic progressive neuro-degenerative disease with loss of dopaminergic neurons in the nigrosome 1 (N1) territory of the substantia nigra pars compacta (SNpc). To date, there has been a major effort to identify changes in the N1 territory by monitoring increases of iron in the SNpc. However, there is no standard protocol being used to visualize or characterize the N1 territory. ⋯ Also, all 9 (100%, 9/9) ET patients showed the N1 sign bilaterally. The mean total structure and mean high susceptibility region for the SN for both IPD and APs patients with bilateral loss of N1 were higher than those of the HCs (p < 0.002). In conclusion, the N1 sign can be consistently visualized using tSWI with a resolution of at least 0.67 mm × 0.67 mm × 1.34 mm and can be seen in 95% of HCs.
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NeuroImage. Clinical · Jan 2020
Involvement of the dentate nucleus in the pathophysiology of amyotrophic lateral sclerosis: A multi-center and multi-modal neuroimaging study.
Amyotrophic lateral sclerosis (ALS) is characterized primarily by motor neuron but also frontotemporal lobar degeneration. Although the cerebellum is involved in both motor and cognitive functions, little is known of its role in ALS. We targeted the dentate nucleus (DN) in the cerebellum and the associated white matter fibers tracts connecting the DN to the rest of the brain using multimodal imaging techniques to examine the cerebellar structural and functional connectivity patterns in ALS patients and hypothesized that the DN is implicated in the pathophysiology of ALS. ⋯ Impaired rsFC is likely due to the observed cerebellar peduncular WM damage given the lack of GM atrophy of the DN. This study demonstrates altered cerebellar rsFC connectivity with motor and extra-motor regions in ALS, and impaired rsFC is likely due to the observed cerebellar peduncular WM damage given the lack of GM atrophy of the DN. The correlation between the altered DN connectivity, and the behavioral data support the hypothesis that the DN plays a pathophysiological role in ALS.
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NeuroImage. Clinical · Jan 2020
Microstructural damage of white-matter tracts connecting large-scale networks is related to impaired executive profile in alcohol use disorder.
Alcohol Use Disorders (AUD) is associated with negative consequences on global functioning, likely reflecting chronic changes in brain morphology and connectivity. Previous attempts to characterize cognitive impairment in AUD addressed patients' performance in single domains, without considering their cognitive profile as a whole. While altered cognitive performance likely reflects abnormal white-matter microstructural properties, to date no study has directly addressed the relationship between a proxy of patients' cognitive profile and microstructural damage. ⋯ Within a widespread pattern of white-matter damage in patients, we found diverse types of relationship linking WM microstructure and executive performance: (i) in the whole sample, we observed a linear relationship involving MD/RD metrics within both 'superficial' white-matter systems mediating connectivity within large-scale brain networks, and deeper systems modulating their reciprocal connections; (ii) in AUD patients vs. controls, a performance-by-group interaction highlighted a MD/AD pattern involving two frontal white-matter systems, including the genu of corpus callosum and cingulum bundle, mediating structural connectivity among central executive, salience and default mode networks. Alterations of prefrontal white-matter pathways are suggestive of abnormal structural connectivity in AUD, whereby a defective interplay among large-scale networks underpins patients' executive dysfunction. These findings highlight different directions for future basic and translational research aiming to tailor novel rehabilitation strategies and assess their functional outcomes.
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NeuroImage. Clinical · Jan 2020
Structure-function relationship of the posterior subthalamic area with directional deep brain stimulation for essential tremor.
Deep Brain Stimulation of the posterior subthalamic area is an emergent target for the treatment of Essential Tremor. Due to the heterogeneous and complex anatomy of the posterior subthalamic area, it remains unclear which specific structures mediate tremor suppression and different side effects. The objective of the current work was to yield a better understanding of what anatomical structures mediate the different clinical effects observed during directional deep brain stimulation of that area. ⋯ Activation patterns for tremor suppression and side effects were similar and predominantly involved the dentato-rubro-thalamic tract and the zona incerta. We found no different activation patterns between different types of side effects and no clear correlation between structure and function. Future studies with use of more sophisticated modelling of activation volumes taking into account fiber heterogeneity and orientation may eventually better delineate these different clusters, which may allow for a refined targeting and programming within this area.