Neural substrates underlying distinct dual cognitive syndromes in Parkinson's disease.

Background: A dual-syndrome hypothesis, which states the cognitive impairments in Parkinson's disease (PD) are attributable to frontostriatal dopaminergic dysregulation and cortical disturbance-each associated with attention/executive and memory/visuospatial dysfunction, respectively-has been widely accepted. This multisystem contribution also underlies highly heterogeneous progression rate to dementia.

Methods: Nondemented PD patients who underwent [I]N-ω-fluoropropyl-2β-carbomethoxy-3β-(4-iodophenyl) nortropane ([I]FP-CIT) SPECT and neuropsychological examinations were enrolled.

Delineating three distinct spatiotemporal patterns of brain atrophy in Parkinson's disease.

The clinical manifestation of Parkinson's disease exhibits significant heterogeneity in the prevalence of non-motor symptoms and the rate of progression of motor symptoms, suggesting that Parkinson's disease can be classified into distinct subtypes. In this study, we aimed to explore this heterogeneity by identifying a set of subtypes with distinct patterns of spatiotemporal trajectories of neurodegeneration. We applied Subtype and Stage Inference (SuStaIn), an unsupervised machine learning algorithm that combined disease progression modelling with clustering methods, to cortical and subcortical neurodegeneration visible on 3 T structural MRI of a large cross-sectional sample of 504 patients and 279 healthy controls.

Involvement of the basal forebrain and hippocampus in memory deficits in Parkinson's disease.

Introduction: Magnetic resonance imaging (MRI)-determined atrophy of the nucleus basalis of Meynert (Ch4) predicts cognitive decline in Parkinson's disease (PD). However, interactions with other brain regions causing the decline remain unclear. This study aimed to describe how MRI-determined Ch4 atrophy leads to cognitive decline in patients with PD.

Frontoparietal-Striatal Network and Nucleus Basalis Modulation in Patients With Parkinson Disease and Gait Disturbance.

Background And Objectives: Neural computations underlying gait disorders in Parkinson disease (PD) are multifactorial and involve impaired expression of stereotactic locomotor patterns and compensatory recruitment of cognitive functions. This study aimed to clarify the network mechanisms of cognitive contribution to gait control and its breakdown in patients with PD.

Methods: Patients with PD were instructed to walk at a comfortable pace on a mat with pressure sensors.

A 37-Year-Old Man With Intellectual Disability Discovered to Have Aspartylglucosaminuria: Implications for the Diagnosis of Genetic Causes.

Objectives: The causes of intellectual disability (ID) are varied, with as many as 1,400 causative genes. We attempted to identify the causative gene in a patient with long-standing undiagnosed ID.

Methods: Although this was an isolated case with no family history, we searched for the causative gene using trio-based whole-exome sequencing (trio-WES), because severe ID is often caused by genetic variations, and inherited metabolic disorders (IMDs) are assumed to be the cause when regression and epilepsy occur.