engleski

Updating in aging: executive function or fluid reasoning?

Updating is an executive function (EF) defined as the ability to replace old irrelevant information with new and relevant ones. It is usually measured with the n-back task in which the participant responds to a stimulus if it is equal to the stimulus shown n steps/positions before. Other updating tasks have been less studied. One such task is the Memory updating (MU) task in which participant must update numbers according to the corresponding mathematical operation. Both, n-back and MU task require building, maintaining, updating, and releasing arbitrary bindings between stimuli, therefore it is expected that tasks measure the same construct, which is separable from other cognitive abilities. The aim of this study was to examine whether the n-back task and MU task measure unique ability, and to investigate their relationship with other lower-and higher-level abilities, fluid reasoning and inhibition respectively. Healthy elderly (N=109) completed the n-backtask, MU task, Raven Progressive Matrices (RPM ; reasoning ability), and Picture-word (PW ; inhibition ability) task. Using the confirmatory factor analysis approach (CFA), three models of updating ability were tested: 1) model with two latent abilities representing two tasks, 2) model with one updating ability, 3) model with one updating ability and a method factor. A model in which updating tasks are saturated with a unique updating factor along with a method factor shows the best fit to data (χ2(6)=12.89, p=0.05 ; CFI=0.96 ; RMSEA=0.1). The results of the structural equation modeling (SEM) analysis showed a significant correlation between the ability to update and fluid reasoning (0.59, p<.01), which indicates a partial overlap of these abilities. On the other hand, the updating ability was not related to inhibition (-0.20, p>.05). These results confirm the partial overlap of updating and fluid reasoning measures, but suggest a dissociation of EF in aging.

updating ability ; fluid reasoning, inhibition

nije evidentirano