|dc.description.abstract||OBJECTIVES: This study aimed to explore age-related differences in dual-tasking. Previous studies report no age-effects in dual-tasking among healthy individuals in comparison to severe dual-tasking impairment in Alzheimer’s disease patients (Baddeley et al., 1986; Logie et al., 2004; MacPherson et al., 2007). This study aimed to replicate these findings using a new experimental paradigm: Fitts’ Box. Dual-tasking ability is thought to rely on the central executive (CE) component of working memory (Baddeley, 1986) along with other executive functions. Thus age-related differences in executive functions were also investigated.
METHODS: The executive functions were switching, inhibition and updating (Miyake et al., 2000). As a comparison, memory and crystallised intelligence were also investigated as these have previously demonstrated age-effects (Salthouse, 1991a; Horn & Cattell, 1967). Dual-tasking was measured by concurrent performance on serial digit-recall and Fitts’ box tasks. The paradigm also allowed the investigation of whether speeded tasks affect dual-tasking, thus two dual-task procedures were employed: standard(disc) and speeded(flashing). Fifty participants were recruited for two age groups (young: N=25; 18-35years, old: N=25; 60+ years).
RESULTS: The findings revealed no significant effect of dual-task on performance: F(1,46)=0.19, p=.67, r=.06 and no significant effect of cohort, F(1,46)=.38, p=.54, r=.19. There was also no significant interaction between the type of participant and the dual-task procedure, F(1,46)=1.66,p=.20. Immediate memory and crystallised intelligence were significantly different between groups. Apart from switching, executive functions demonstrated age differences. There was no relationship between executive functions and dual-task flashing, yet a significant relationship between dual-task disc, and inhibition was found.
IMPLICATIONS: The majority of the hypotheses were confirmed, and results concerning age-effects in executive functions and their relationship with dual-tasking contributed to research by providing some insight about the alleged fractionation of the CE (Baddeley, 1998). The study replicated previous findings by using a new experimental paradigm which was developed as an improvement from past methodologies. It is suggested that with further pruning, Fitts’ box could provide a novel and pioneering method to assess dual-tasking ability. The potential clinical use of this new paradigm is discussed.||en