Effects of Exercise on Electroencephalogram Parameters and Cognitive Functions in Mild Cognitive Impairment Patients

Abstract

Mild cognitive impairment (MCI) is becoming an emerging problem for developing countries where there is increase in expected age. There is no specific therapeutic treatment for these patients. Evidence suggests that the combination of both exercise and physical activity has a greater effect on MCI patients, than exercise or physical activity alone. The objective of this study was to determine the short and long-term effects of aerobic exercise and Xbox 360 Kinect cognitive games on slowness, complexity, coherence in electroencephalography (EEG) signals, somatosensory evoke potentials (SEPs) and cognitive tests in MCI patients. A parallel group design study was conducted in the Pakistan Railways General Hospital, Rawalpindi. Patients were selected and randomly divided into Xbox 360 Kinect cognitive games group (n=22), aerobic exercise group (n=21), single session aerobic exercise group (n=14) and their respective control groups (n=22, n=22, n=14 respectively). The outcome measures were slowness, complexity coherence of EEG, SEPs and mini-mental state examination (MMSE), Montreal cognitive assessment scale (MoCA) and trail making test (TMT) A and B. EEG was recorded using the EMOTIV EPOC with 14 channels and Refa 72-channel stationary system. Patients were assessed before and after one session of intervention for short-term effects and after six weeks for long-term effects. After one session of aerobic exercise there were significant improvements in slowness (delta waves; 0.678+0.035 vs 0.791+0.033; p=0.015) and complexity (0.601+0.051 vs 0.470+0.042; p=0.027) of the EEG in aerobic exercise treated group as compared to no-aerobic exercise group. After six weeks there were significant xxii improvements in slowness (delta waves; 0.581+0.036 vs 0.815+0.025; p=0.005) and complexity (0.751+0.045 vs 0.533+0.046; p=0.001) of the EEG in the aerobic group as compared to no-aerobic group. Moreover, significant improvements were observed in the MMSE (p=0.032), MoCA (p=0.036), TMT-A (p=0.005) and TMT-B (p=0.007) in aerobic exercise group as compared to no-aerobic group. After one session of Xbox 360 Kinect cognitive games intervention, delta (0.704+0.025; p=0.013), theta (0.128+0.009; p=.0.00127) waves and complexity of EEG (0.642+0.042; p=0.008) significantly improved, in eyes closed state. Whereas after six weeks intervention of games, delta (0.673+0.029; p=0.013), theta (0.129+0.013; p=0.002), beta2 waves (0.044+0.009; p=0.046), complexity of EEG (0.051+0.042; p=0.016), MMSE (26.25+0.347vs 23.722+0.731; p=0.003), MoCA (25.65+0.310vs 22.00+0.504; p=0.0001), TMT-A (1.429+0.234vs 2.225+0.259; p=0.028) and TMT-B (2.393+0.201vs 3.780+0.195; p=0.0001) improved significantly. These changes were not observed in the control group. Upon comparison of aerobic exercise and Xbox 360 Kinetic cognition games, it was found that aerobic exercise has more short and long-term therapeutic effects on MCI patients as compared to Xbox 360 Kinect cognitive games group. Single session of aerobic exercise significantly decreased the inter-hemisphere coherence, however, it improved intrahemisphere coherence. After single session of aerobic exercise, there was significant decrease in peak amplitude of SEPs in MCI patients, however, no effect on SEPs peak latencies was found. This study suggests that aerobic exercise and Xbox 360 Kinetic cognitive games have dual/2-fold beneficial effect on age associated MCI. First one, the progression of MCI is slowed down significantly. Second, there is evidence of xxiii improvement in the cognitive state of MCI patients. Such intervention for treatment purpose could be helpful to rehabilitate MCI patients in third world countries.