The study may lead to an understanding of why the brain begins to lose its ability to remember more important things.
Researchers have suspected for some time that mental decline may be due to a decreasing ability to "tune out" irrelevant information.
A study from the University of Canada found that was the case when older people were getting a brain scan. During the scans, the older brains responded more to the background buzzing and banging from the scanner itself.
Participants were also tested to see if they recognized faces. The older subjects who failed the test showed increased activity in parts of the brain responsible for processing distracting sounds and sights.
There's no definite link at this point, but researchers think they're onto something. More information on the study is available in the Journal of Neuroscience.