Assessing Dual-Task Ability: Developing a New Paradigm

Abstract

Whilst there have been many attempts to design a paradigm to assess dual tasking ability throughout the lifespan, studies have failed to avoid potential pitfalls in their methodologies. By combating three main problems with previous methods, this project aims to develop a paradigm that can yield valid and accurate results. Two single tasks were chosen as they satisfied three key conditions; 1. They loaded onto separate domains of the working memory model (Baddeley & Hitch, 1974) 2. Demand level was able to be varied to equate differences between group ability level. 3. They did not involve the use of Response Time (RT) tasks which could potentially infer an illusionary age effect. The tasks were; immediate serial digit recall and a tapping task involving a Fitts’ law box. The box could be used to create a RT dependent and a non RT dependent dual task assessment. Two samples, of younger and older adults respectively took part. Testing was in two parts involving a small battery of neuropsychological tests and the main dual task assessments. Each component task was calibrated to each individual’s ability level and were combined to provide results for each age group in single and dual task conditions. There were two dual task assessments made for each individual – RT dependent and non RT dependent. Results indicated that an age effect was produced on the RT dependent dual task assessment, but not the non RT dependent assessment. This indicates that RT dependent tasks bias younger samples leading to an illusionary age effect being produced confirming that studies that utilise an RT dependent task to assess dual tasking are inherently flawed.