Study leader Philip Ko and Dr. Brandon Ally, both of Vanderbilt University, said the study involved 11 older adults about age 67 and 13 younger adults of approximately 23 years of age. They had them complete a task called visual change detection, which consisted of viewing two, three or four colored dots and memorizing their appearance.
These dots disappeared, and then after a few seconds the participants were presented with a single dot appearing in one of the memorized colors or a new color.
The accuracy of their response -- behavioral measure -- was considered to reflect how well they memorized the colors. Electroencephalographic -- the recording of electrical activity along the scalp -- was also collected from the participants as they performed the task for a neural measure of their memory capacity.
The study found while behavioral measures indicated a lower capacity in older adults than younger adults to memorize items, the neural measure of memory capacity was very similar in both groups. In other words, during the maintenance stage, both groups stored the same number of items.
However, older adults store the items at a lower resolution than younger adults, resulting in impaired recollection, Ko said. Unlike older adults, younger adults may be able to use perceptual implicit memory, a different kind of visual memory, to give them a "boost" when they are trying to retrieve the stored information, Ko added.
The findings were published the journal Attention, Perception & Psychophysics.