Health care providers and the medical community are beginning to consider hearing an important element of cognition and overall health, according to recent trends in the medical community. More and more, researchers are conducting studies which show the important link between cognition and hearing health, and the overall importance of hearing as a way for individuals who are aging to retain independence, inclusion, and overall quality of life.
Although some of the studies are conducted by hearing technology manufacturers, the findings that, overall hearing is a very important component to retaining cognitive function, are across the board regardless of the sponsors of the studies. In fact, many of these studies have been conducted by Neurologists and Neuroscientists as well, and all support the same basic conclusion: Wearing hearing aids, and the consistent use of assistive listening devices does have a positive impact on cognitive function in the aging brain.
You can read one such study here, with links to other studies as well.