Mild Cognitive Impairment (MCI) Due to Alzheimer's Disease

The goal of this clinical trial is to learn if a wearable ultrasound device, called ATTN201, is safe and easy to use. The study is for adults ages 65 and older who have mild cognitive impairment (MCI) and a buildup of a protein called amyloid in the brain. Amyloid buildup is an early sign of Alzheimer's disease. The ATTN201 device sends low-intensity sound waves to a deep area of the brain that helps control sleep. The aim is to boost deep-sleep brain waves. These brain waves may help the brain clear away waste, including amyloid. The main questions it aims to answer are: 1. What, if any, issues do participants have when using the ATTN201 device? 2. Can participants complete the full study schedule? Researchers will compare focused ultrasound to unfocused ultrasound. Unfocused ultrasound is a look-alike treatment. It feels and sounds the same but is not aimed at the brain target. The comparison will show if the focused treatment changes sleep brain waves, blood markers of Alzheimer's disease, or memory and thinking. Participants will: * Visit the study site for memory and thinking tests, blood draws, a health check, and MRI scans of the brain * Record their sleep at home for at least 5 days with a sleep diary, a watch-like sensor, and a headband that measures brain waves * Be assigned by chance to focused or unfocused ultrasound * Take part in 10 nap sessions over 2 weeks while wearing the device, at the study site or at home * Return for a final visit to repeat the first tests, and may return for an optional visit 3 months later

The goal of this clinical trial is to learn if repetitive transcranial magnetic stimulation (rTMS), a non-invasive form of brain stimulation, can improve short-term memory in people with early Alzheimer's disease (AD). The study will also evaluate the safety of this approach. The main questions it aims to answer are: * Does rTMS applied to the cerebellum improve short-term memory in people with early AD? * How does this stimulation affect brain activity and connectivity measured by MRI? Researchers will compare active rTMS to sham rTMS (a look-alike procedure that does not deliver brain stimulation) to see if rTMS works to improve memory. Participants will: * Complete a screening visit with medical and memory assessments * Be randomly assigned to receive either active rTMS or sham rTMS (neither participants nor researchers will know the assignment during treatment) * Receive 20 rTMS sessions over 4 weeks (about 20 to 30 minutes per session) * Undergo two MRI scans, one before and one after treatment * Complete memory and thinking tests and questionnaires at baseline, immediately after treatment, and at 3- and 6-month follow-up visits Participation in the study will last about 6 months. The rTMS is generally well tolerated. The most common side effects include mild headache and scalp discomfort during treatment, which are usually short-lasting. MRI is non-invasive and safe for most people. Study procedures will be reviewed to ensure participant safety. Participants may or may not benefit directly from this study. People who receive active rTMS may experience improvement in memory. This research may help improve understanding of memory function in AD and support development of new treatments.

This project aims to longitudinally profile plasma-derived GDEVs and plasma biomarkers of neuroinflammation across three stages of the AD continuum (Subjective Cognitive Decline, Mild Cognitive Impairment, and Alzheimer's Dementia), exploring their association with biomarkers of amyloidopathy, tauopathy and neurodegeneration, cognitive status and clinical outcome over time. Moreover, GDEVs - collected from subjects at different disease stages - will be used to treat human neurons derived from induced pluripotent stem cells (iPSCs) from healthy controls in order to assess the induced differential neurotoxic or priming effects. This dual translational approach may help identify early pathogenic signatures of neuroinflammation and elucidate their role in disease progression.

Gut problems, such as constipation, can have an important impact on quality of life of people who have them, and have been associated with higher risk of developing neurological diseases such as Parkinson's or Alzheimer's disease. Recent studies suggest that gut problems may also have implications for the progression of these diseases, as constipation is a risk factor for faster Parkinson's and Alzheimer's progression. However, how constipation and brain diseases are linked is unknown. Previous research has suggested that gut changes may lead to inflammation, which could play a role in accelerating the progression of both movement and memory problems in Parkinson's and memory and thinking problems in people with cognitive impairment. Methane is a gas that is naturally produced by microorganisms in the gut. Levels of methane can be measured using a simple breath test. Higher methane levels in the breath are thought to be more common in people with Parkinson's disease (PwP) when compared to people without Parkinson's (healthy controls) and have been associated with gut symptoms, particularly constipation, as well as worse movement problems in PwP, although they are less understood in conditions that affect memory and thinking (like dementia or mild cognitive impairment). The investigators want to better understand the changes in the gut of PwP and people with cognitive impairment (e.g. mild cognitive impairment or dementia). They will compare breath methane levels in PwP, people with cognitive impairment, people with REM Sleep Behaviour Disorder (a sleep condition linked to a higher risk of developing Parkinson's) and healthy participants. Participants will be followed-up over time to assess how methane levels are linked to changes in the blood and the stools, gut function, and clinical symptoms. This study has 2 components: Component 1: observational study, where the study investigators will follow 200 participants over 2 visits, 18 months apart. The study will recruit 4 groups of people: 50 people with Parkinson's disease, 50 people at high risk of developing Parkinson's disease (people with REM Sleep behaviour disorder), 50 people with other conditions affecting cognition (e.g. dementia, mild cognitive impairment), and 50 healthy controls. Component 2: study with 15 people with Parkinson's, who produce high methane levels, to test whether a probiotic (Lactobacillus reuteri) affects how much methane is produced.

The present study will administer the drug leronlimab to 20 participants who are above 50 years old with Alzheimer's disease (AD) or mild cognitive impairment (MCI) due to AD. While leronlimab is considered safe in other diseases like Human Immunodeficiency Virus (HIV) and certain types of cancer, its safety and tolerability in AD will be tested for the first time. The main purpose of this study is to learn: 1. Is this drug safe for participants with AD and MCI due to AD? 2. Does leronlimab change levels of brain inflammation? The results of this study could lead to future studies with more participants that will test whether leronlimab may slow or prevent the decline in thinking abilities and brain function in this group of participants. Using leronlimab for Alzheimer's disease is experimental, which means that the Food and Drug Administration (FDA) has not approved leronlimab for this purpose. Participants will be asked to take leronlimab once a week for 12 weeks in our clinic or in their own home. Participants will also be asked to complete the below procedures before and after taking leronlimab for 12 weeks: 1. Undergo 2 types of brain scans, Positron Emission Tomography (PET) and Magnetic Resonance Imaging (MRI). 2. Visit our clinic for routine lab work, an electrocardiogram (ECG), and a physical exam. 3. Donate blood so the researchers can better understand how leronlimab affects levels of inflammation and proteins related to AD in the blood. 4. Undergo a series of tests and questionnaires that test thinking abilities. 5. Have weekly phone calls with researchers to let them know if there are side effects while taking this drug.

Mild cognitive impairment (MCI) is a transitional risk state that occurs between the normal aging process and Alzheimer's dementia (AD). On average 32% of patients with MCI will progress to dementia, 62% will stay stable, and about 6% will return to normal cognition at subsequent visits. Current treatment for MCI includes cholinesterase inhibitors (donepezil, galantamine and rivastigmine), and NMDA receptor antagonists (memantine) which delay or slow the worsening of symptoms and treat cognitive symptoms (memory loss, confusion, and problems with thinking and reasoning). Despite currently ongoing drug studies and modest clinical benefits of currently approved drug treatments, there continues to remain a need for treatments for long term symptomatic improvement of MCI with fewer and less severe side effects. Photobiomodulation (PBM) therapy also called low-level laser (or light) therapy (LLLT) is a safe, non-invasive, non-thermal (no significant heat is generated) method of therapy which uses either visible red or near-infrared (NIR) light to stimulate, heal and repair damaged or dying tissue cells. This study proposes to use the Neuro RX Gamma device (version 2) to deliver NIR light energy to particular brain regions which are dysfunctional in MCI participants.

The goal of this clinical trial is to learn if mindfulness meditation can improve outcomes in older adults with and without cognitive impairment. The main questions it aims to answer are: 1. How does mindfulness impact thinking and memory? 2. How does mindfulness influence brain function and structure? 3. How does mindfulness affect daily function and quality of life? Researchers will compare all outcomes to one other groups. In one group, individuals will participate in a mindfulness class intervention; in the other group, individuals will not engage in any active interventions immediately, but will be placed on a waitlist for the mindfulness intervention. Researchers will compare all outcomes between the groups groups to determine whether the mindfulness interventions leads to greater improvement compared to no intervention (waitlist group). Participants will: * Be randomly assigned to participate in the mindfulness intervention, or no immediate intervention (waitlist) * Complete paper-and-pencil cognitive testing, surveys, computerized tasks, and neuroimaging measures (EEG and MRI) before and after the intervention Outcomes will be assess at baseline, 2 months, 4 months and 6 months.

The Anti-Aβ mAb CED Study is a prospective, longitudinal coverage with evidence development (CED) study using clinical data, patient assessments, and administrative claims data of the Medicare population, conducted in accordance to the National Coverage Determination (NCD) on Monoclonal Antibodies Directed Against Amyloid for the Treatment of Alzheimer's Disease (AD).