Striatum and Hippocampus on Different Time Scales
Huntington DiseaseAlzheimer DiseaseTime processing is fundamental to survival and goal reaching in humans. Different time scales (seconds, minutes, and beyond) are processed through specific cognitive processes involving different neural representations. It is generally agreed that time scale in seconds-to-minutes range named "interval timing" would be anatomically linked to the striatum. Indeed, it is possible to demonstrate a deficit of interval timing processes in patients suffering from striatal damage (Huntington's disease). However, recent findings show involvement of a second brain structure, the hippocampus, in interval timing processing in the minutes range, suggesting an interaction between the striatum and hippocampus. Presumably, patients with hippocampal damage (Alzheimer's disease) would specifically show a decrease in performance for this minutes-range time scale. This study aims to provide a better understanding of the role of the striatum in the treatment of time and its interactions with other brain structures such as the hippocampus. More specifically, it is unclear whether the striatum plays a platform role that would always be involved regardless of the time scale, as suggested by the unified model of time or whether different brain structures is solicited according to the time scale, as suggested by the modular system model. In order to elucidate these issues, a potential double dissociation between brain structures and time scales will be tested.
Study of AGB101 in Mild Cognitive Impairment Due to Alzheimer's Disease
Mild Cognitive ImpairmentProdromal Alzheimer's DiseaseThe primary objective of the study is to evaluate the efficacy of AGB101 on slowing cognitive and functional impairment as measured by changes in the Clinical Dementia Rating-Sum of Boxes (CDR-SB) score as compared with placebo in participants with mild cognitive impairment due to Alzheimer's Disease (MCI due to AD) also known as prodromal AD. Participants will be randomized to receive placebo or AGB101 (220 mg), once daily for 78 weeks. Secondary objectives are to assess the effect of AGB101 compared with placebo on clinical progression as measured by the Alzheimer's Disease Assessment Scale-Cognitive Subscale 14 (ADAS-cog14), Mini-Mental State Examination (MMSE) and Functional Activities Questionnaire (FAQ).
Deep Brain Stimulation for Alzheimer's
Alzheimer DiseaseEarly Onset2 moreThis project will investigate the potential of Deep Brain Stimulation to improve cognitive abilities and counteract the effects of Alzheimer's disease. Deep Brain Stimulation electrodes targeting the Nucleus Basalis of Meynert (NB) will be implanted bilaterally in a cohort of patients. NB is the sole source of acetylcholine to the neocortex. Such stimulation may not only treat the cognitive symptoms but may have disease-modifying effects. Drawing from animal experiments in non-human primates that showed success of this approach, intermittent stimulation will be delivered at 60 pulses per second for 20 seconds of each minute for one hour per day. The study team will recruit patients, shortly after first being diagnosed with Alzheimer's disease. The study design will test the safety and efficacy of stimulation, potential benefits in cognitive function assessed with a battery of neurocognitive tests, cholinergic neurotransmission evaluated with Positron Emission Tomography, and ability to reverse Alzheimer's biomarkers, including beta amyloid and tau in the cerebrospinal fluid. Successful completion of this project will lead to a potential new intervention for the cognitive impairments of Alzheimer's disease.
Tau Networks in Psychotic Alzheimer's Disease
Alzheimer DiseaseAlzheimer Disease With Delusions1 moreThis research project aims to understand the brain mechanisms behind the manifestation of psychotic symptoms in Alzheimer´s disease (AD), and nature of the unique relationship with tau pathology. Amongst the cognitive manifestations of psychosis are impairments related to frontal circuits (social cognition, working memory and executive function deficits). The investigator's previous work suggests a role of tau pathology (one of the hallmarks of AD neuropathology) in the manifestation of psychosis in AD. However, the cerebral mechanisms that underly this association remain poorly understood. The overarching aim of the study is is to investigate the mechanisms by which tau network pathology may promote the presentation of psychosis in AD.
Noninvasive Temporal Interference Stimulation: Modulating Associative Memory by Targeting Deep-brain...
Healthy AgingMemory Disorders in Old Age2 moreAlzheimer's disease and its preclinical stages are characterized by progressive neurodegenerative changes in the hippocampi and default mode network resulting in dysfunctions in episodic memory and its central part the associative memory. Associative memory allows for learning and remembering the relationship between unrelated items. Previous research suggests that non-invasive brain stimulation can influence associative memory but with the caveat of quite a small precision and relatively small effects due to the ability only influence superficial brain areas. Novel Brain stimulation techniques such as temporal interference stimulation (TIS) allow overcoming these caveats by allowing focal non-invasive deep brain stimulation. The main goal of this pilot clinical trial is to modulate associative memory among healthy seniors by influencing the cortico-hippocampal circuits using TIS. Secondly, the goal is to use functional magnetic resonance imaging (fMRI) and EEG to explore the neural correlates of TIS effects on brain networks and find biomarkers that allow predicting better response to brain stimulation.
A Study of Caregiver Connections Via Technology in Dementia
Caregiver StressDementia4 moreThis research is being done to develop a unique matching process for caregivers of persons living with dementia, such as Alzheimer's disease, Lewy body dementia, frontotemporal degeneration, or other dementia syndromes. Dementia caregivers often assume greater caregiving burden than do non-dementia caregivers, and the caregiving duration tends to be longer. Many caregivers do not have the adequate support they need. Peer-to-peer support has been shown to improve quality of life, more engagement with services, improve caregiver health, and reduce hospitalizations in the person they are caring for. This study will help determine whether caregivers of persons with dementia would find a technology-based caregiver matching program valuable for the purpose of emotional support.
Investigating if a Stronger tDCS Intensity is More Effective for Improving Naming Ability in People...
Alzheimer DiseaseThere is currently little symptomatic therapy for Alzheimer's Disease (AD) and nothing effective for individuals with Frontotemporal dementia (FTD). However, neuromodulation with transcranial direct current stimulation (tDCS) has the potential to be a clinically effective therapy for both AD and FTD. The challenge now is to specify the parameters and conditions under which tDCS is most effective to transition from the laboratory to clinical medicine. tDCS studies typically report significant group effects despite the variability demonstrated among participants, with some showing clear, meaningful improvement, while others only show statistical improvement or none at all. These variable results may be related to the conventional stimulation intensity level of 2mA. The investigators predict that administering tDCS at 4.0 mA, a more significant number of participants would show a meaningful response, and those who improve at 2mA may improve even more from 4.0mA due to having a larger electric field produced. The investigators aim to test this hypothesis in people with Alzheimer's Disease.
SAFE at Home: A Service to Provide Social Engagement to Community-Dwelling Persons With Dementia...
Alzheimer DiseaseDementia4 moreThe proposed Phase 1 study will involve initial development and evaluation of a new service called Social Activities For Engagement at Home or SAFE at Home (SaH). SaH will enable PWD to participate in videoconference-based group activities with their peers-i.e., other PWD. SaH sessions will be facilitated by highly trained "Engagement Professionals," who will be SaH staff members that have a background in recreation therapy, activity coordination, or a similar field. The proposed study has three Specific Aims: Aim 1. Develop an Alpha version of the SaH app, including app infrastructure and preliminary activity content for live group sessions, as well as staff training and coaching modules. Aim 2. Examine the app's acceptability/feasibility (by assessing attendance, session length, and engagement/affect). Aim 3. Examine satisfaction with the app by directly eliciting feedback from PWD and life enrichment staff.
Tau Protein and SV2a Imaging in Patients With Tau Protein-related Diseases
Alzheimer DiseaseProgressive Supranuclear Palsy1 moreTau protein has been identified as one of the key pathological features of Tau proteinopathies, such as Alzheimer's disease (AD), progressive supranuclear palsy (PSP), frontotemporal dementia (FTD). Tau protein-targeted PET imaging can detect the amount and distribution of Tau protein deposition in human body, and has great research and application value in the diagnosis and evaluation of Tau protein disease. This study will be the first to introduce a complete quantitative, repeatable detection and analysis method in China. For the SV2a tracer [18F]MNI-1126, cross-sectional evaluation of its imaging in patients with Tau protein-related diseases and normal controls will be carried out. Later, longitudinal clinical symptoms and two tracers will be evaluated in patients with Tau protein-related diseases and normal controls.([18F]APN1607 and [18F]MNI1126) Imaging follow-up to explore longitudinal changes in brain Tau protein deposition and synaptic density in Tau protein-related diseases, thus providing support for future clinical drug trials using imaging biomarkers.
Vanderbilt Memory and Aging Project
Alzheimer DiseaseAging7 moreThis study will use an observational cohort to cross-sectionally and longitudinally relate vascular health to clinical, imaging, and biological markers of early Alzheimer's disease and cerebrovascular disease among aging adults. Adjusting for relevant clinical covariates, we will test the hypothesis that vascular health is associated with clinical, brain magnetic resonance imaging (MRI), neuropsychological, and cerebrospinal fluid markers of early cerebrovascular and Alzheimer's disease changes (i.e., prior to the onset of significant cognitive decline or dementia). Secondarily, we will examine medical and genetic factors that might mediate associations between vascular health and brain aging, such as inflammatory processes, insulin resistance, and genetic factors (e.g., APOE, a susceptibility risk factor for dementia). Findings will advance knowledge regarding the role that vascular health plays in brain aging.