The lack of effective preventive and treatment strategies against Alzheimer’s disease is an alarming problem. There is a need to find effective preventive and treatment strategies that will offer hope to an aging population, to Alzheimer’s disease patients, and their caregivers.
An urgent need to identify these strategies has risen among older adults at increased risk for memory loss. Among people at the greatest risk for Alzheimer’s disease are older adults diagnosed with Mild Cognitive Impairment (MCI). Some of the earliest signs of memory loss and possible Alzheimer’s disease involve damage to a part of the brain called the hippocampus. Scientists have been searching for drugs to stop the rate of memory loss by trying to preserve the neurons in the hippocampus, thereby improving its memory function. These attempts have failed.
However, recent research has shown that exercise and physical activity benefit cognitive function and may offer neuronal protection. Amazingly, the protective effects of exercise on brain function have been shown to be extremely robust in the hippocampus, the very brain structure targeted early on in Alzheimer’s disease. But these effects have never been demonstrated in older adults at greater risk for Alzheimer’s disease, such as in those diagnosed with MCI. As you can imagine, there has been excitement and great interest among scientists, but until now only speculation, regarding whether or not the protective effects of exercise on the hippocampus and memory function also occur in people who show signs of accelerated memory loss.
Our studies test the effects of exercise in those most at risk for Alzheimer’s disease--people diagnosed with MCI, people with a genetic risk, and those who have metabolic risk factors such as a past stroke or TIA. Exercise appears to offer cognitive benefits with a low risk of side effects. However, it is unknown if exercise training will improve brain function and brain blood flow in people with MCI. To measure the effects of exercise on brain function we will use magnetic resonance imaging (MRI) to measure brain activation during simple memory test consisting of famous and non-famous names. We will also use MRI to measure the amount of blood flow in the brain after the exercise program, particularly in the hippocampus. Our central hypothesis is that exercise promotes a neural reserve that can be drawn upon to promote enhanced brain function and cognitive performance in the face of early neurodegenerative processes related to Alzheimer’s disease. This work will advance our understanding the effects of exercise on brain function in those at increased risk for AD, with the long term-goal of determining if exercise may help prevent or delay conversion to Alzheimer’s disease.