In a new study, Brandeis University researchers conclude that older adults with mild-to-moderate hearing loss may expend so much cognitive energy on hearing accurately that their ability to remember spoken language suffers as a result.
The study, published in the latest issue of Current Directions in Psychological Science, showed that even when older adults could hear words well enough to repeat them, their ability to memorize and remember these words was poorer in comparison to other individuals of the same age with good hearing.
"There are subtle effects of hearing loss on memory and cognitive function in older adults," said lead author Arthur Wingfield, Nancy Lurie Marks Professor of Neuroscience at the Volen National Center for Complex Systems at Brandeis University. "The effect of expending extra effort comprehending words means there are fewer cognitive resources for higher level comprehension."
"This extra effort in the initial stages of speech perception uses processing resources that would otherwise be available for downstream operations, such as encoding the material in memory or performing higher-level comprehension operations," explained co-authors Patricia A. Tun and Sandra L. McCoy.
A group of older adults with good hearing and a group with mild-to-moderate hearing loss participated in the study. Each participant listened to a fifteen-word list and was asked to remember only the last three words. All words were delivered at the same volume. Both groups showed excellent recall for the final word, but the hearing-loss group displayed poorer recall of the two words preceding it.