Ativação cortical e desempenho funcional de idosos saudáveis submetidos a uma dupla tarefa

Abstract

Introduction: In daily activities, individuals need to perform simultaneous tasks, such as walking and observing obstacles, to prevent accidents. However, morphological findings in the elderly showed a reduction in the grey matter in the frontal lobe, a region necessary for the execution of tasks of the executive function, which is essential in the Double Task (DT). The electroencephalogram (EEG) is used to observe brain dynamics by capturing the electrical flow. DT training is an important tool for motor and cognitive gains in the elderly. However, studies that demonstrate brain patterns in DT performance are scarce. Objective: The objective of this study was to investigate how DT can influence the pattern of brain activation in healthy elderly people. Methodology: Descriptive observational cross-sectional study, in which individuals between 65 and 75 years old were investigated. The subjects were evaluated by means of the sociodemographic evaluation form, Mini-Mental State Examination (MMSE), Short Physical Performance Battery (SPPB), Functional Gait Assessment (TDF) and analysis of Electroencephalography (EEG) - Emotiv EPOC, in order to observe cortical activation in DT performance. Statistical Analysis: The data were prepared using statistical software SPSS-20. The initial analysis was performed using the mean, standard deviation and frequency values. Data were analyzed according to the Emotiv EPOC® standards and using the Mann-Whitney, Wilcoxon and Spearman correlation tests. Significance of 5% was adopted. Results: 23 individuals were included, most of them female (60.9%) and with predominant schooling in elementary school (30%). The duration of TDF1 was 1 minute and 38 seconds (median 98 seconds). There was significance between the performance of the TDF with education (p = 0.012), age (p = 0.018) and MMSE (p = 0.019). In the analysis of the alpha and beta waves, there was a trend of the greater potential for activation of F3 channels and less potential for activation of F5 channels. There were statistical correlations between SPPB and the F3 channel (alpha p = 0.020; ρ = -0.480 and beta p = 0.013; ρ = -0.509) and O2 channel (alpha p = 0.042; ρ = -0.426 and beta p = 0.032; ρ = -0.447); and between the P7 channel and the MMSE (alpha p = 0.034; ρ = -0.444) and beta p = 0.025; ρ = -0.466), all indicating a negative and moderate correlation. The direct hemisphere channels and the executive cortical areas were the most activated. Conclusion: The data obtained indicate that DT activated the motor areas that more contribute to executive functions rather than other cortical areas. These other areas, in turn, were also activated, albeit to a lesser extent, by the need for the cortex to meet instant motor and cognitive demands, mainly due to the compensation of cortical weakness in the elderly. In addition, this study showed that elderly people with better functional and cognitive performance require less neural effort and attention in the frontal and parietal areas on the left and right occiput, to perform the double task.