As the number of aging persons in our society increases, the importance of finding ways of maintaining physical and mental functioning also increases. Research has shown that overall there is a decline in cognitive functioning with aging. However, this decline is not universal and there is great variability among individuals as they age. Identifying factors that can help maintain cognitive functioning with aging can be of personal benefit to individuals and to society as a whole. The "use it or lose it" theory hypothesizes that continued stimulation plays a role in maintaining cognitive functioning with aging. Previous studies have shown mixed results regarding this hypothesis. This proposal hypothesized that there would be an inverse correlation between participation in activities and the rate of change in cognitive functioning in a sample of nursing home residents. The results did not support the main hypothesis; however, there was indication that activity level may be correlated with maintaining cognitive functioning in a dementia population.