The effect of ageing on dual tasking performance: A tale of two paradigms

Dual tasking is the ability to perform two tasks simultaneously. There is some debate in literature as to whether or not ageing has a specific effect on dual tasking ability. Our study investigated this area further by assessing the performance of a younger group of 25 adults aged 19-23 years and an older group of 25 healthy adults 65-88 in two slightly differing dual task paradigms. In both paradigms the participants were required to perform a tapping task combined with a digit recall task. Difficulty in the first paradigm was adjusted by increasing the tapping speed required. In the second paradigm, difficulty of the tapping task was adjusted by increasing the level of accuracy required. Task difficulty was titrated for each individual and single task scores were controlled for when assessing dual task performance. An array of Neuropsychological tests were also carried out to test memory and executive functioning. The younger group performed significantly better than the older group in the dual task paradigm adjusted for speed but there was no significant difference between the groups in the paradigm adjusted for accuracy. This suggested that dual tasking ability was not impaired by ageing and that the difference in performance in the paradigm adjusted for speed was due to an exaggeration of the slower processing speed in older adults. The older group was found to perform significantly worse than the younger group in almost all the measures of memory and executive functioning