- 期刊
【論文摘要】Age-related Differences in EEG Gamma Band During Six Sensory-Challenging Tasks
【論文摘要】不同年齡在六種感覺挑戰任務之腦電圖伽馬波差異
摘要
Background and Purpose: With advances in brain imaging techniques, electroencephalography (EEG) can be used to investigate brain activities in upright positions. Our literature search revealed few EEG studies using sensory-challenging balancing tasks. The aims of this study were to 1) examine gamma band in six sensory conditions with difficulty increasing in a stepwise manner and 2) compare the differences between elderly and young individuals. Methods: We used 21-channel EEG during the Sensory Organization Test (SOT), with withdrawal visual or altered visual/ somatosensory inputs, in healthy young (n = 10, 22.5 ± 2.7 yr) and elderly (n = 5, 68.7 ± 5.0 yr.) participants. Changes in spectral power during 20-sec standing relative to the 1.5-sec standing baseline in the gamma band (31-50 Hz) were evaluated. Results: There was significantly decrease in gamma oscillations of the temporal-parietal-occipital area in Condition 2 than in Condition 1. In terms of the SOT equilibrium score, the elderly group underperformed the young group (F1,13 = 46.480, p ＜ 0.001), and these differences were amplified in Conditions 5 and 6. Comparing to the young group, there were significantly increment in gamma waves of the frontal area in the elderly group in Conditions 1 and 6, as well as in the occipital area especially in SOT Conditions 4, 5 and 6. Conclusion: Decreased gamma activity in the temporal-parietal-occipital area in the eyes-closed condition might signify an increased need for sensory integration. The elderly participants have increased gamma oscillations in the frontal area, representing more demanding of selective or divided attention, and in the occipital area, signifying increased demand of visual attention when they attend to solve the conflicted somatosensory information by increasing the relative weighting of visual information. Clinical Relevance: The results suggest that, even in healthy elderly adults, inefficient central modulation during challenging postural conditions could be an internal factor that contributes to the risk of fall.