Grant: Project Grant - PA: Neurosciences, Mental Health and Addiction

Alzheimer's disease (AD) is a type of dementia that causes problems with cognition (memory, thinking), function and behaviour. Currently, a group of drugs called cholinesterase inhibitors are used to improve cognition, however benefits from these drugs are modest and AD patients eventually worsen even with continued use. Moreover, they have significant side-effects such as loss of appetite, nausea, vomiting and diarrhea. As a result, there remains a critical need for treatments, particularly those focused on mild AD when quality of life is still potentially excellent. While transcranial direct current stimulation (tDCS; electrical brain stimulation with a safe, weak, and non-painful current to the brain) has been shown to improve memory in some people with mild AD with minimal side-effects, recent evidence suggests that tDCS works better when brain circuits are active. As exercise increases brain activity, it may help to make tDCS even more effective when performed right before treatment. This study will assess whether combining exercise and tDCS can help improve memory in mild AD, and whether this combination improves memory better than either exercise or tDCS alone. Patients will be randomly assigned to receive either 1) exercise before tDCS, 2) exercise before sham (non-active) tDCS, or 3) tDCS alone (with exercise education only) for two weeks. Cognition and behaviour, as well as blood measures reflecting brain and blood vessel health will be assessed before, during, and after treatment. This study may identify a safe, new, non-invasive treatment approach that preserves cognition in early AD, therefore having major health implications.