Lexical-semantic search related to side of onset and putamen volume in Parkinson's disease.

Parkinson's disease (PD) is characterized by dopaminergic cell loss and reduced striatal volume. Prior studies have demonstrated striatal involvement in access to lexical-semantic knowledge and damage to this structure may be evident in the lexical properties of responses. Semantic fluency task responses from early stage, non-demented PD participants with right (PD-R) or left (PD-L) lateralizing symptoms were compared to matched controls on lexical properties (word frequency, age of acquisition) and correlated with striatal volumes segmented from T1-weighted brain MR images.

Cortical Thinning and Cognitive Impairment in Parkinson's Disease without Dementia.

Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized clinically by motor dysfunction (bradykinesia, rigidity, tremor, and postural instability), and pathologically by the loss of dopaminergic neurons in the substantia nigra of the basal ganglia. Growing literature supports that cognitive deficits may also be present in PD, even in non-demented patients. Gray matter (GM) atrophy has been reported in PD and may be related to cognitive decline.

Predicting the multi-domain progression of Parkinson's disease: a Bayesian multivariate generalized linear mixed-effect model.

Background: It is challenging for current statistical models to predict clinical progression of Parkinson's disease (PD) because of the involvement of multi-domains and longitudinal data.

Methods: Past univariate longitudinal or multivariate analyses from cross-sectional trials have limited power to predict individual outcomes or a single moment. The multivariate generalized linear mixed-effect model (GLMM) under the Bayesian framework was proposed to study multi-domain longitudinal outcomes obtained at baseline, 18-, and 36-month.

Association of neurobehavioral performance with R2* in the caudate nucleus of asymptomatic welders.

Objectives: Welding fumes contain several metals including manganese (Mn) and iron (Fe) that may affect the nervous system. Previous studies of potential welding-related neurotoxicity have focused primarily on Mn exposure. The current study examined neurobehavioral and brain imaging changes in asymptomatic welders and their associations with both Mn and Fe exposure measurements.

Decreased leftward 'aiming' motor-intentional spatial cuing in traumatic brain injury.

Objective: To characterize the mediation of attention and action in space following traumatic brain injury (TBI).

Method: Two exploratory analyses were performed to determine the influence of spatial 'Aiming' motor versus spatial 'Where' bias on line bisection in TBI participants. The first experiment compared performance according to severity and location of injury in TBI.

The pattern of gray matter atrophy in Parkinson's disease differs in cortical and subcortical regions.

Cortical and subcortical gray matter (GM) atrophy may progress differently during the course of Parkinson's disease (PD). We delineated and compared the longitudinal pattern of these PD-related changes. Structural MRIs and clinical measures were obtained from 76 PD with different disease durations and 70 Controls at baseline, 18-, and 36 months.

Side of motor onset is associated with hemisphere-specific memory decline and lateralized gray matter loss in Parkinson's disease.

Background: Parkinson's disease (PD) is a neurodegenerative disorder that generally begins with asymmetric motor symptoms that persist over time. This suggests that the dysfunction in the nigrostriatal motor circuit may be lateralized. The present study examined whether the asymmetric motor presentation is associated with hemisphere-specific cognitive decline and lateralized gray matter volume loss.

Early cortical gray matter loss and cognitive correlates in non-demented Parkinson's patients.

Background: Whereas the motor dysfunction in Parkinson's disease (PD) has been related to deficits in basal ganglia (BG) structures, neural correlates of cognitive changes remain to be fully defined. This study tested the hypothesis that cognitive changes in non-demented PD may be related to cortical gray matter (GM) loss.

Methods: High-resolution T1-weighted magnetic resonance images of the brain and comprehensive cognitive function tests were acquired in 40 right-handed, non-demented PD subjects and 40 matched controls.