Table 4.

Brain activity due to sensory challenges to static balance control.

Name, year	Balance challenge	Modality	Mobile	Spatial location	Activity
Chang et al., 2016	Platform perturbations with and without synced VR in older adults	EEG	No	Parietal-occipital region	Gamma, beta bands
				Frontal-central region	Theta band
				Occipital lobe	Alpha band
Del Percio et al., 2007	Standing with eyes open or closed	EEG	No	Rt. ventral CP area	Alpha band ERD amplitude
Karim et al., 2013	Fixed floor, eyes open light/dark, sway-referenced floor, eyes open light/dark	fNIRS	No	Bi. Lat. temporal-parietal areas	Activation
Mitsutake et al., 2015	Head rotations on a rotating platform	fNIRS	No	Cz, T3, T4, F3, F4	Activation
Ouchi et al., 1999	Bipedal or unipedal stance; eyes open or closed	PET	No	Cerebellar anterior vermis, visual cortex, PFC	Activation
Petrofsky and Khowailed, 2014	Eyes open/closed, surface compliance, base of support in amputees vs. controls	EEG	No	Fz, F3, F4, Cz, C3, C4, POz, P3, and P4	Alpha, beta, and sigma band power
Pirini et al., 2011	Auditory feedback in eyes open vs. eyes closed scenarios	EEG	No	Rt inferior parietal	Alpha power
				Lt temporo-parietal, Lt temporo-occipital	Gamma power
Slobounov et al., 2015	Maintain balance in heel-to-toe stance while subjected to 2D or 3D VR moving room	EEG	No	Frontal midline	Theta power
Slobounov et al., 2013	Optical flow with various degrees of uncertainty	EEG	No	Frontal-central areas	Theta power
Tse et al., 2013	Eyes open/ closed; Firm/foam surface; Regular stance/heel-toe position	EEG	No	Parietal and central areas	Beta and Sigma band power
Varghese et al., 2015	Standing with eyes closed and feet together or feet heel-to-toe position	EEG	No	Cz	Amplitude of N100 evoked prior to balance reaction

TM, treadmill; OG, overground; VR, virtual reality; lt., left; rt., right; bi. lat., bilateral; ERD, event related desynchronization.