Evaluation of visuospatial performance in elderly patients with and without Alzheimer's disease using the dual task

Background and Objective: The purpose of this study was the evaluation of visuospatial task performance in elderly patients with and without Alzheimer's disease using the dual task.
Materials and Methods: This study was a quasi-experimental and between subjects and within subjects design was used in it. The 23 subjects (11 females and 12 males) with an age range of 62 to 81 years 13 patients with Alzheimer's disease (AD) and 10 healthy elderly subjects (EC) with normal cognitive function participated in this study. Identifying people with Alzheimer's disease and healthy people was performed based on physician diagnoses and the Short Portable Mental Status Questionnaire (SPMSQ). After obtaining the overall error (E) or Root Mean Squared Error (RMSE), and variable error (VE) were calculated for the tracking task, participants performed cognition task (counting month of year in duration of 20 seconds) in two conditions (simple, difficult) with visiouospatial tracking task simultaneously.
Results: The results showed that the AD group compared to the matched controls (EC) in the visuospatial task performance in Single-task condition, more errors were committed. Also level of difficulty on accuracy drop and consistency the tracking task at dual-task conditions was significant (p < 0.05). But AD disease effect not significant (p > 0.05).
Conclusion: A decline in visuospatial task affected by the increased interference at response level were due to defects in the mechanisms of selective attention in both groups.