Older adults typically have trouble identifying the speech they hear, especially in noisy environments. Fortunately, compared to younger adults, older adults are better able to compensate for difficulties identifying the speech they hear by recruiting the visual system. However, the extent to which older adults can benefit from visual input, and how this influence relates to age-related changes in brain structure and function, have not been thoroughly investigated. The general purpose of this study is to determine how age-related changes in brain structure and function affect how well people hear and see. This study seeks participants with normal hearing to mild hearing loss, who also have normal or corrected-to-normal vision.

With this research study, we want to learn if methylphenidate (Ritalin® and others) helps people with Alzheimer's disease and apathy (lack of interest or concern for things that others find moving or exciting).