Background: The differential contributions of the cerebellum and parietal lobe to coordination between hand transport and hand shaping to an object have not been clearly identified.
Objective: To contrast impairments in reach-to-grasp coordination, in response to object location perturbation, in patients with right parietal and cerebellar lesions, in order to further elucidate the role of each area in reach-to-grasp coordination.
Method: A two-factor design with one between subject factor (right parietal stroke; cerebellar stroke; controls) and one within subject factor (presence or absence of object location perturbation) examined correction processes used to maintain coordination between transport-to-grasp in the presence of perturbation. Sixteen chronic stroke participants (eight with right parietal lesions and eight with cerebellar lesions) were matched in age (mean = 61 years; standard deviation = 12) and hand dominance with 16 healthy controls. Hand and arm movements were recorded during unperturbed baseline trials (10) and unpredictable trials (60) in which the target was displaced to the left (10) or right (10) or remained fixed (40).
Results: Cerebellar patients had a slowed response to perturbation with anticipatory hand opening, an increased number of aperture peaks and disruption to temporal coordination, and greater variability. Parietal participants also exhibited slowed movements, with increased number of aperture peaks, but in addition, increased the number of velocity peaks and had a longer wrist path trajectory due to difficulties planning the new transport goal and thus relying more on feedback control.
Conclusion: Patients with parietal or cerebellar lesions showed some similar and some contrasting deficits. The cerebellum was more dominant in controlling temporal coupling between transport and grasp components, and the parietal area was more concerned with using sensation to relate arm and hand state to target position.
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http://dx.doi.org/10.3389/fnhum.2015.00293 | DOI Listing |
Neuroimage Rep
December 2024
Department of Pediatrics, Division of Developmental-Behavioral Pediatrics, Stanford University, Stanford, CA, USA.
Background: Severe neonatal inflammatory conditions in very preterm infants (VPT: <32 weeks gestational age, GA) are linked to adverse neurodevelopmental outcomes. Differences in white matter (WM) microstructure of the corpus callosum (CC) have been observed at age 6 in VPT children with a history of severe neonatal inflammation. The goal of this study was to determine whether these CC differences can be detected at term-equivalent age using diffusion MRI (dMRI), and whether neonatal inflammation is associated with altered WM in additional tracts implicated in the encephalopathy of prematurity.
View Article and Find Full Text PDFJ Neurol
January 2025
Department of Neurology, School of Medical Sciences, University of Campinas-UNICAMP, Universitaria "Zeferino Vaz", Rua Tessália Vieira de Camargo, 126. Cidade, Campinas, SP, 13083-887, Brazil.
Background: Skeletal and cardiac muscle damage have been increasingly recognized in female carriers of DMD pathogenic variants (DMDc). Little is known about cognitive impairment in these women or whether they have structural brain damage.
Objective: To characterize the cognitive profile in a Brazilian cohort of DMDc and determine whether they have structural brain abnormalities using multimodal MRI.
Exp Neurobiol
December 2024
Department of Brain and Cognitive Engineering, Korea University, Seoul 02841, Korea.
Research on brain aging using resting-state functional magnetic resonance imaging (rs-fMRI) has typically focused on comparing "older" adults to younger adults. Importantly, these studies have often neglected the middle age group, which is also significantly impacted by brain aging, including by early changes in motor, memory, and cognitive functions. This study aims to address this limitation by examining the resting state networks in middle-aged adults via an exploratory whole-brain ROI-to-ROI analysis.
View Article and Find Full Text PDFRadiol Case Rep
March 2025
Department of Neurology, Delafontaine Hospital, Seine Saint-Denis, France.
Hepatic encephalopathy may trigger cortical laminar necrosis (CLN), which is characterized by diffuse symmetric cortical lesions. We report a 56-year-old woman with liver cirrhosis who presented with prolonged floor station, reduced alertness and left hemiplegia. Blood ammonia level was elevated.
View Article and Find Full Text PDFNeurosci Res
January 2025
Center for Brain Behavior and Metabolism, University of Lübeck, Germany. Electronic address:
Pronouns create cohesive links in discourse by referring to previously mentioned elements. Here, we focus on pronominalization during speech production in three experiments employing ERP and fMRI methodologies. Participants were asked to produce two short sentences describing a man or woman using an object.
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