In Vivo Tau and Neurodegeneration Imaging in a Family With the Presenilin 1 Met146Leu Pathogenic Variant.

Objectives: We investigated tau and neurodegeneration patterns and clinical phenotypes in carriers of a specific pathogenic variant in the PSEN1 gene and 1 nonaffected relative.

Methods: We included 3 symptomatic carriers of the c.436 A>C, p.

Insular monoaminergic deficits in prodromal α-synucleinopathies.

Methods: This study assessed data from two cohorts of patients with alpha-synucleinopathies (University of Brescia and University of Rome Tor-Vergata cohorts). Consecutive participants with video-polysomnography-confirmed iRBD, Parkinson's disease (PD), dementia with Lewy bodies (DLB) and controls underwent neurological, clinical and I-FP-CIT SPECT imaging assessments. Individuals with iRBD were longitudinally monitored to collect clinical phenoconversion to PD or DLB.

Persistent dysfunctions of brain metabolic connectivity in long-covid with cognitive symptoms.

Purpose: Our study examines brain metabolic connectivity in SARS-CoV-2 survivors during the acute-subacute and chronic phases, aiming to elucidate the mechanisms underlying the persistence of neurological symptoms in long-COVID patients.

Methods: We perfomed a cross-sectional study including 44 patients (pts) with neurological symptoms who underwent FDG-PET scans, and classified to timing infection as follows: acute (7 pts), subacute (17 pts), long-term (20 pts) phases. Interregional correlation analysis (IRCA) and ROI-based IRCA were applied on FDG-PET data to extract metabolic connectivity in resting state networks (ADMN, PDMN, EXN, ATTN, LIN, ASN) of neuro-COVID pts in acute/subacute and long-term groups compared with healthy controls (HCs).

Neurocognitive mechanisms of emotional interference in native and foreign languages: evidence from proficient bilinguals.

Currently available data show mixed results as to whether the processing of emotional information has the same characteristics in the native (L1) as in the second language (L2) of bilinguals. We conducted a functional magnetic resonance imaging (fMRI) experiment to shed light on the neurocognitive mechanisms underlying bilinguals' emotional processing in L1 and L2 during an emotional interference task (i.e.

Development of a prediction model of conversion to Alzheimer's disease in people with mild cognitive impairment: the statistical analysis plan of the INTERCEPTOR project.

Background: In recent years, significant efforts have been directed towards the research and development of disease-modifying therapies for dementia. These drugs focus on prodromal (mild cognitive impairment, MCI) and/or early stages of Alzheimer's disease (AD). Literature evidence indicates that a considerable proportion of individuals with MCI do not progress to dementia.

Coupling motor evoked potentials and brain [F]FDG-PET in Amyotrophic Lateral Sclerosis: preliminary findings on disease severity.

Background: The diagnosis of amyotrophic lateral sclerosis (ALS) is primarily clinical, supported by the electromyographic examination to reveal signs of lower motor neuron damage. Identifying reliable markers of upper motor neuron (UMN) involvement is challenging. On this regard, the role of transcranial magnetic stimulation-induced motor-evoked potentials (TMS-MEPs), and its relationship with UMN burden, is still under investigation.

Sharing brain imaging data in the Open Science era: how and why?

The sharing of human neuroimaging data has great potential to accelerate the development of imaging biomarkers in neurological and psychiatric disorders; however, major obstacles remain in terms of how and why to share data in the Open Science context. In this Health Policy by the European Cluster for Imaging Biomarkers, we outline the current main opportunities and challenges based on the results of an online survey disseminated among senior scientists in the field. Although the scientific community fully recognises the importance of data sharing, technical, legal, and motivational aspects often prevent active adoption.

Deep brain stimulation of the subthalamic nucleus for Parkinson's disease: A network imaging marker of the treatment response.

Subthalamic nucleus deep brain stimulation (STN-DBS) alleviates motor symptoms of Parkinson's disease (PD), thereby improving quality of life. However, quantitative brain markers to evaluate DBS responses and select suitable patients for surgery are lacking. Here, we used metabolic brain imaging to identify a reproducible STN-DBS network for which individual expression levels increased with stimulation in proportion to motor benefit.

The diagnostic and prognostic value of tau-PET in amnestic MCI with different FDG-PET subtypes.

Objectives: Mild cognitive impairment presenting with an amnestic syndrome (aMCI) and amyloid positivity is considered due to AD. Many subjects, however, can show an overall very slow progression relevant for differential diagnosis, prognosis, and treatment. This study assessed PET biomarkers, including brain glucose metabolism, tau, and amyloid load, in a series of comparable aMCI at baseline, clinically evaluated at follow-up.

Distinctive clinical and imaging trajectories in SWEDD and Parkinson's disease patients.

A proportion of patients clinically diagnosed with Parkinson's disease (PD) can have a I-FP-CIT-SPECT scan without evidence of dopaminergic deficit (SWEDD), generating a debate about the underlying biological mechanisms. This study investigated differences in clinical features, I-FP-CIT binding, molecular connectivity, as well as clinical and imaging progression between SWEDD and PD patients. We included 36 SWEDD, 49 de novo idiopathic PD, and 49 healthy controls with I-FP-CIT-SPECT from the Parkinson's Progression Markers Initiative.

Heterogeneity and overlap in the continuum of linguistic profile of logopenic and semantic variants of primary progressive aphasia: a Profile Analysis based on Multidimensional Scaling study.

Background: Primary progressive aphasia (PPA) diagnostic criteria underestimate the complex presentation of semantic (sv) and logopenic (lv) variants, in which symptoms partially overlap, and mixed clinical presentation (mixed-PPA) and heterogenous profile (lvPPA +) are frequent. Conceptualization of similarities and differences of these clinical conditions is still scarce.

Methods: Lexical, semantic, phonological, and working memory errors from nine language tasks of sixty-seven PPA were analyzed using Profile Analysis based on Multidimensional Scaling, which allowed us to create a distributed representation of patients' linguistic performance in a shared space.

Mapping brain metabolism, connectivity and neurotransmitters topography in early and late onset dementia with lewy bodies.

Introduction: Early-onset dementia with Lewy bodies (EO-DLB) is associated with rapid cognitive decline and severe neuropsychiatric symptoms at onset.

Methods: Using FDG-PET imaging for 62 patients (21 EO-DLB, 41 LO (late-onset)-DLB), we explored brain hypometabolism, and metabolic connectivity in the whole-brain network and resting-state networks (RSNs). We also evaluated the spatial association between brain hypometabolism and neurotransmitter pathways topography.

The role of parietal beta-band activity in the resolution of visual crowding.

Visual crowding is the difficulty in identifying an object when surrounded by neighbouring flankers, representing a bottleneck for object perception. Crowding arises not only from the activity of visual areas but also from parietal areas and fronto-parietal network activity. Parietal areas would provide the dorsal-to-ventral guidance for object identification and the fronto-parietal network would modulate the attentional resolution.

Demographic, clinical, biomarker, and neuropathological correlates of posterior cortical atrophy: an international cohort study and individual participant data meta-analysis.

Background: Posterior cortical atrophy is a rare syndrome characterised by early, prominent, and progressive impairment in visuoperceptual and visuospatial processing. The disorder has been associated with underlying neuropathological features of Alzheimer's disease, but large-scale biomarker and neuropathological studies are scarce. We aimed to describe demographic, clinical, biomarker, and neuropathological correlates of posterior cortical atrophy in a large international cohort.

Atypical brain FDG-PET patterns increase the risk of long-term cognitive and motor progression in Parkinson's disease.

Introduction: Brain hypometabolism patterns have been previously associated with cognitive decline in Parkinson's disease (PD). Our aim is to evaluate the impact of single-subject fluorodeoxyglucose (FDG)-PET brain hypometabolism on long-term cognitive and motor outcomes in PD.

Methods: Forty-nine non-demented PD patients with baseline brain FDG-PET data underwent an extensive clinical follow-up for 8 years.

The impact of tau deposition and hypometabolism on cognitive impairment and longitudinal cognitive decline.

Introduction: Tau and neurodegeneration strongly correlate with cognitive impairment, as compared to amyloid. However, their contribution in explaining cognition and predicting cognitive decline in memory clinics remains unclarified.

Methods: We included 94 participants with Mini-Mental State Examination (MMSE), tau positron emission tomography (PET), amyloid PET, fluorodeoxyglucose (FDG) PET, and MRI scans from Geneva Memory Center.

FDG-PET markers of heterogeneity and different risk of progression in amnestic MCI.

Introduction: Amnestic mild cognitive impairment (aMCI) is emerging as a heterogeneous condition.

Methods: We looked at a cohort of N = 207 aMCI subjects, with baseline fluorodeoxyglucose positron emission tomography (FDG-PET), T1 magnetic resonance imaging, cerebrospinal fluid (CSF), apolipoprotein E (APOE), and neuropsychological assessment. An algorithm based on FDG-PET hypometabolism classified each subject into subtypes, then compared biomarker measures and clinical progression.

Comparison of univariate and multivariate analyses for brain [18F]FDG PET data in α-synucleinopathies.

Background: Brain imaging with [18F]FDG-PET can support the diagnostic work-up of patients with α-synucleinopathies. Validated data analysis approaches are necessary to evaluate disease-specific brain metabolism patterns in neurodegenerative disorders. This study compared the univariate Statistical Parametric Mapping (SPM) single-subject procedure and the multivariate Scaled Subprofile Model/Principal Component Analysis (SSM/PCA) in a cohort of patients with α-synucleinopathies.

Occipital hypometabolism is a risk factor for conversion to Parkinson's disease in isolated REM sleep behaviour disorder.

Purpose: Isolated REM sleep behaviour disorder (iRBD) patients are at high risk of developing clinical syndromes of the α-synuclein spectrum. Progression markers are needed to determine the neurodegenerative changes and to predict their conversion. Brain imaging with F-FDG PET in iRBD is promising, but longitudinal studies are scarce.

Comparing two picture naming tasks in primary progressive aphasia: Insights from behavioural and neural results.

Picture naming tests are widely used to evaluate language impairments in neurodegenerative diseases, especially in Primary Progressive Aphasia (PPA). The available tests differ for many factors affecting the performance, e.g.