Saying versus touching: age differences in short-term memory are affected by the type of response.

We examined whether the type of response used to report items recalled from short-term memory affects the age difference in verbal and spatial memory spans. Younger and older adults viewed either a series of letters or a series of locations in a grid, and then they reported their memory for the items either vocally or by using a touch screen. Overall, age differences were larger for spatial memory spans than for verbal memory spans, replicating previous results. Changing the response modality affected only older adults' verbal spans, which were approximately one item higher with a vocal response than with a manual response. This resulted in a smaller age difference for verbal items reported vocally than for any other condition. The results can best be explained by age-related difficulties in both spatial processing and in dealing with stimulus-response incongruity.