Somatic CAG repeat expansion in blood associates with biomarkers of neurodegeneration in Huntington's disease decades before clinical motor diagnosis.

Huntington's disease (HD) is an autosomal dominant neurodegenerative disease with the age at which characteristic symptoms manifest strongly influenced by inherited HTT CAG length. Somatic CAG expansion occurs throughout life and understanding the impact of somatic expansion on neurodegeneration is key to developing therapeutic targets. In 57 HD gene expanded (HDGE) individuals, ~23 years before their predicted clinical motor diagnosis, no significant decline in clinical, cognitive or neuropsychiatric function was observed over 4.

Dual-task gait training improves cognition and resting-state functional connectivity in Parkinson's disease with postural instability and gait disorders.

Objectives: To assess whether dual-task gait/balance training with action observation training (AOT) and motor imagery (MI) ameliorates cognitive performance and resting-state (RS) brain functional connectivity (FC) in Parkinson's disease (PD) patients with postural instability and gait disorders (PIGD).

Methods: 21 PD-PIGD patients were randomized into 2 groups: (1) DUAL-TASK + AOT-MI group performed a 6-week training consisting of AOT-MI combined with practicing observed-imagined gait and balance exercises; and (2) DUAL-TASK group performed the same exercises combined with landscape-videos observation. At baseline and after training, all patients underwent a computerized cognitive assessment, while 17 patients had also RS-fMRI scans.

Age-related vulnerability of the human brain connectome.

Multifactorial models integrating brain variables at multiple scales are warranted to investigate aging and its relationship with neurodegeneration. Our aim was to evaluate how aging affects functional connectivity of pivotal regions of the human brain connectome (i.e.

Italian reference values and brain correlates of verbal fluency index - standard verbal fluency test - to assess executive dysfunction in ALS.

In amyotrophic lateral sclerosis (ALS), verbal fluency index (V) is used to investigate fluency accounting for motor impairment. This study has three aims: (1) to provide V reference values from a cohort of Italian healthy subjects; (2) to assess the ability of V reference values ( standard verbal fluency test [VFT]) in distinguishing ALS patients with and without executive dysfunction; and (3) to investigate the association between V and brain structural features of ALS patients. We included 180 healthy subjects and 157 ALS patients who underwent neuropsychological assessment, including VFT and V, and brain MRI.

Cerebellar alterations in Parkinson's disease with postural instability and gait disorders.

Background: Few studies interrogated the involvement of cerebellum in modulating gait in Parkinson's disease (PD) patients with postural instability and gait disorders (PD-PIGD). This study aimed at assessing cerebellar atrophy and activity alterations during functional MRI (fMRI) gait-simulating motor- and dual-tasks in PD-PIGD.

Methods: Twenty-one PD-PIGD and 23 healthy controls underwent clinical assessment, structural MRI, and fMRI including a motor-task (foot anti-phase movements) and a dual-task (foot anti-phase movements while counting backwards by threes).

Awareness impairment in Alzheimer's disease and frontotemporal dementia: a systematic MRI review.

This review aims to define awareness impairment and related disturbances in neurodegenerative diseases, including Alzheimer's disease (AD) and frontotemporal lobar degeneration (FTLD) spectrum of disorders. An update of the available scientific literature on the use of magnetic resonance imaging (MRI) in the study of awareness in these disorders is also offered. MRI plays an important role in the characterization of neurodegenerative signatures and can increase our knowledge on brain structural and functional correlates of awareness.

Brain structural abnormalities and cognitive changes in a patient with 17q21.31 microduplication and early onset dementia: a case report.

Objectives: We describe brain structural damage and cognitive profile evolution of an adult patient with 17q21.31 microduplication, a rare condition associated with psychomotor delay, behavioural disturbances and poor social interaction.

Methods: A.

Longitudinal clinical, cognitive, and neuroanatomical changes over 5 years in GBA-positive Parkinson's disease patients.

Objective: To study the longitudinal disease course of Parkinson's disease (PD) patients with glucocerebrosidase (GBA) mutation (GBA-positive) compared to PD non-carriers (GBA-negative) along a 5-year follow-up, evaluating changes in clinical and cognitive outcomes, cortical thickness, and gray-matter (GM) volumes.

Methods: Ten GBA-positive and 20 GBA-negative PD patients underwent clinical, neuropsychological, and MRI assessments (cortical thickness and subcortical, hippocampal, and amygdala volumes) at study entry and once a year for 5 years. At baseline and at the last visit, each group of patients was compared with 22 age-matched healthy controls.

Action Observation and Motor Imagery Improve Dual Task in Parkinson's Disease: A Clinical/fMRI Study.

Background: Action observation training and motor imagery may improve motor learning in Parkinson's disease (PD).

Objectives: The objectives of this study were to assess mobility and balance (performing motor and dual tasks) and brain functional reorganization following 6 weeks of action observation training and motor imagery associated with dual-task gait/balance exercises in PD patients with postural instability and gait disorders relative to dual-task training alone.

Methods: Twenty-five PD-postural instability and gait disorder patients were randomized into 2 groups: the DUAL-TASK+AOT-MI group performed a 6-week gait/balance training consisting of action observation training-motor imagery combined with practicing the observed-imagined exercises; the DUAL-TASK group performed the same exercises combined with watching landscape videos.

The art gallery maze: a novel tool to assess human navigational abilities.

Humans differ widely in their ability to navigate effectively through the environment and in spatial memory skills. Navigation in the environment requires the analysis of many spatial cues, the construction of internal representations, and the use of various strategies. We present a novel tool to assess individual differences in human navigation, consisting of a virtual radial-arm maze presented as an art gallery to explore whether different sets of instructions (intentional or incidental) affect subjects' navigation performance.

An update on magnetic resonance imaging markers in AD.

The purpose of the present review is to provide an update of the available recent scientific literature on the use of magnetic resonance imaging (MRI) in Alzheimer's disease (AD). MRI is playing an increasingly important role in the characterization of the AD signatures, which can be useful in both the diagnostic process and monitoring of disease progression. Furthermore, this technique is unique in assessing brain structure and function and provides a deep understanding of evolution of cerebral pathology.

Early functional MRI changes in a prodromal semantic variant of primary progressive aphasia: a longitudinal case report.

Objective: To assess longitudinal patterns of brain functional MRI (fMRI) activity in a case of prodromal semantic variant of a primary progressive aphasia (svPPA).

Methods: Clinical, cognitive and neuroimaging data (T1-weighted and task-based fMRI during silent naming [SN] and object knowledge [OK]) were obtained at baseline, month 8 and month 16 from a 49-year-old lady presenting with anomias and evolving to overt svPPA in 8 months.

Results: At baseline, the patient showed isolated anomias and mild left anterior temporal pole atrophy.

Crossed aphasia confirmed by fMRI in a case with nonfluent variant of primary progressive aphasia carrying a GRN mutation.

Objectives: To characterize patterns of language lateralization in a right-handed woman with nonfluent/agrammatic primary progressive aphasia (nfvPPA) clinical picture despite showing a prevalent right-sided brain damage.

Methods: We report a case of a 58-year-old woman with nfvPPA diagnosis (age at onset = 55) previously described as a crossed aphasia case with progranulin mutation. At 2 years from the first visit, patient underwent 3DT1-weighted and a task-based functional MRI (fMRI).