View clinical trials related to Logopenic Progressive Aphasia.
Filter by:While many have strongly suggested that transcranial direct current stimulation (tDCS) may represent a beneficial intervention for patients with primary progressive aphasia (PPA), this promising technology has not yet been applied widely in clinical settings. This treatment gap is underscored by the absence of any neurally-focused standard-of-care treatments to mitigate the devastating impact of aphasia on patients' family, work, and social lives. Given that tDCS is inexpensive, easy to use (it is potentially amenable to home use by patients and caregivers), minimally invasive, and safe there is great promise to advance this intervention toward clinical use. The principal reason that tDCS has not found wide clinical application yet is that its efficacy has not been tested in large, multi-center, clinical trials. In this study, scientists in the three sites that have conducted tDCS clinical trials in North America-Johns Hopkins University and the University of Pennsylvania in the US, and the University of Toronto in Canada, will collaborate to conduct a multi-site, Phase II clinical trial of tDCS a population in dire need of better treatments.
The purpose of this study is to investigate the feasibility of using repetitive transcranial magnetic stimulation (rTMS) - a form of non-invasive brain stimulation - to improve language functioning in individuals who have the logopenic variant of primary progressive aphasia (PPA-L) - a slowly progressive impairment of language, characterized by difficulties with word-finding, sentence repetition and sentence comprehension.
Alzheimer's disease (AD) is the leading neurodegenerative disease of aging characterized by multiple cognitive impairments. Given the recent failures of disease-modifying drugs, the current focus is on preventing or mitigating synaptic damage that correlates with cognitive decline in AD patients. Transcranial Direct Current Stimulation (tDCS) is a safe, non-invasive, non-painful electrical stimulation of the brain that is shown to act as a primer at the synaptic level when administered along with behavioral therapy, mostly involving language, learning and memory. Previous studies have shown that tDCS over the left angular gyrus (AG) improves language associative learning in the elderly through changes in functional connectivity between the AG and the hippocampus. The investigators' previous clinical trial on the effects of tDCS in neurodegenerative disorders has also shown augmented effects of lexical retrieval for tDCS. In the present study the investigators will compare the effects of active vs. sham tDCS over the AG-an area that is part of the default mode network but also a language area, particularly important for semantic integration and event processing-in two predominant AD variants: probable AD with amnesic phenotype (amnesic/typical AD) and probable AD with non-amnesic (language deficit) phenotype also described as logopenic variant PPA with AD pathology (aphasic/atypical AD). The investigators aim to: (1) determine whether active high-definition tDCS (HD-tDCS) targeting the left AG combined with a Word-List Learning Intervention (WordLLI) will improve verbal learning; (2) identify the changes in functional connectivity between the stimulated area (AG) and other structurally and functionally connected areas using resting-state functional magnetic resonance imaging; (3) identify changes in the inhibitory neurotransmitter GABA at the stimulation site using magnetic resonance spectroscopy. Furthermore, the investigators need to determine the characteristics of the people that may benefit from the new neuromodulatory approaches. For this reason, the investigators will evaluate neural and cognitive functions as well as physiological characteristics such as sleep, and will analyze the moderating effects on verbal learning outcomes. Study results can help provide treatment alternatives as well as a better understanding of the therapeutic and neuromodulatory effects of tDCS in AD, thus improving patients' and caregivers' quality of life.
AD afflicts over 5.5. million Americans and is one of the most expensive diseases worldwide. In AD the variant in which language functions are most affected are referred to as 'logopenic variant Primary Progressive Aphasia' (lvPPA). Language deficits dramatically impair communication and quality of life for both patients and caregivers. PPA usually has an early onset (50-65 years of age), detrimentally affecting work and family life. Studies have identified verbal short-term memory/working memory (vSTM/WM) as a primary deficit and cause of language impairment. In the first cycle of this award, the investigators asked the question of whether language therapy effects could be augmented by electrical stimulation. The investigators conducted the largest to-date randomized, double-blind, sham-controlled, crossover, clinical trial to determine the effects of transcranial direct current stimulation (tDCS) in PPA. The investigators found that tDCS over the left inferior frontal gyrus (L_IFG), one of the major language hubs in the brain, significantly enhanced the effects of a written naming and spelling intervention. In addition, findings demonstrated that tDCS modulates functional connectivity between the stimulated area and other networks (e.g. functionally and structurally connected areas), and that tDCS modulates the inhibitory neurotransmitter gamma-aminobutyric acid (GABA). In terms of tDCS, the investigators have been identified several predictors to determine the beneficience of tDCS including (a) PPA variant, (b) initial performance on cognitive/language tasks, particularly vSTM/WM, and (c) initial white-matter integrity and structure. These findings support the notion that tDCS benefits generalize beyond the treatment tasks and has led to the important question of the present study: How can we implement treatments to product benefits that maximally generalize to untrained but vital language/cognitive functions. To address the above question, the investigators will test recent neuroplasticity theories that claim that the benefits of neuromodulation to language-specific areas generalize to other language functions within the language network, while neuromodulation of a domain-general/multiple-demands area generalizes to both domain-general, executive and language functions. The two areas to be stimulated will be the supramarginal gyrus (SMG) and left dorsolateral prefrontal cortex (DLPFC) respectively. The left supramarginal gyrus (L_SMG) in particular, specializes in phonological processing, namely phonological verbal short-term memory (vSTM), i.e., the ability to temporarily store phonological (and graphemic) information in order. The domain of vSTM affects many language tasks (repetition, naming, syntax), which makes it an ideal treatment target and the L_SMG an ideal stimulation target, since generalization of tDCS effects to other language tasks is driven by the function (computation) of the stimulated area. By testing a fundamental principle of neuromodulation in a devastating neurodegenerative disorder, the investigators will significantly advance the field of neurorehabilitation in early-onset dementias. Aim 1: To determine whether vSTM/WM behavioral therapy combined with high definition (HD)-tDCS over the L_SMG will induce more generalization to language-specific tasks than to executive tasks, whereas stimulation over the LDPFC will induce equivalent generalization to both executive and language-specific tasks. Aim 2: To understand the mechanism of tDCS by measuring tDCS-induced changes in network functional connectivity (FC) and GABA in the LSMG and LDPFC. The investigators will carry out resting-state functional magnetic resonance imaging (rsfMRI), (MPRAGE), diffusion-weighted imaging (DWI), perfusion imaging (pCASL), and magnetic resonance spectroscopy (MRS), before, after, and 3-months post-intervention. Aim 3: To identify the neural, cognitive, physiological, clinical and demographic characteristics (biomarkers) that predict sham, tDCS, and tDCS vs. sham effects on vSTM and related language tasks in PPA. The investigators will evaluate neural (functional and structural connectivity, cortical volume, neuropeptides, and perfusion), cognitive (memory, attention, executive) and language functions, clinical (severity), physiological (sleep), and demographic (age, gender) characteristics, and the investigators will analyze the effects on vSTM and other language/cognitive outcomes immediately after intervention and at 3 months post-intervention.
This study attempts to identify two types of AD by using clinical and cognitive tasks and brain imaging. The subtypes of AD are separated into a "typical" group (memory loss) and a "variant" group (language, visuospatial, and other cognitive difficulties). Performance on the clinical tasks and brain imaging will be compared among the young-onset Alzheimer's disease group, a late-onset Alzheimer's disease group, and a control group.