Effect of aging in cortial activity during sensory integration to balance posture

Abstract

Postural balance maintenance is a fundamental ability of human movements, achieved and maintained by a complex set of the sensory-motor control system. The sensory inputs from the somatosensory, visual and vestibular systems are integrated by the CNS to generate the motoric response required to balance the posture. Postural balance becomes very crucial in seniors. This study aims at identifying the impact of aging on postural balance, and the sensory integration involved in the postural balance, as well as the cortical response during static balance and sensory integration. In this study, 20 young active students 24.64 ± 2.47 years of age and 20 active seniors 68.45 ± 5.37 years of age underwent a sensory organisation test (SOT) with Balance Master. Along with coupled 32-channel wireless MOVE EEG 10/20 system. An IIR filter with a low cut-off of 0.5 Hz and a high cut-off of 120 Hz, were applied to the EEG data. The independent component ocular correction was used to remove the artifacts. The power spectrum and functional localisation were analysed in the delta, theta, alpha, beta and gamma frequency bands. The senior participants exhibited a decline in their ability to maintain postural balance p < 0.001 and balance strategies p < 0.05, together with decreased sensory integration abilities to balance the posture p < 0.001 when compared with the young participants. The senior participants also showed high-level cortical modulation, during postural balance. Delta and theta activities decreased, while alpha, beta and gamma activities increased under somatosensory visual and vestibular influence. Further, in functional localisation beta and gamma activities get reduced in young participants, and alpha activity was noted increased in senior participants. The significant finding from this study was that the cortical response was higher during the static postural balance in the seniors when compared with the young participants. As the sensory information to balance the posture was isolated, the cortical activity was observed to further decrease in young participates about baseline. To improve the postural balance of seniors training comprises physical challenges, coordination and cognition is proposed, e.g. dance training with music, which can be helpful to improve the balance ability.