Vestibular-Evoked Responses Indicate a Functional Role for Intrinsic Foot Muscles During Standing Balance

Autor: Brandon G. Rasman, Jonathan W. Wallace, Brian H. Dalton
Rok vydání: 2018
Předmět:
Zdroj: Neuroscience. 377:150-160
ISSN: 0306-4522
DOI: 10.1016/j.neuroscience.2018.02.036
Popis: Maintaining standing balance involves multisensory processing and integration to produce dynamic motor responses. Electrical vestibular stimulation (EVS) delivered over the mastoid processes can be used to explore the vestibular control of balance. The purpose of this study was to determine whether intrinsic foot muscles exhibit vestibular-evoked balance responses and to characterize the traits associated with these responses. Electromyography (EMG) of the abductor hallucis (AH), abductor digiti minimi (ADM) and medial gastrocnemius (MG) and anterior-posterior (AP) forces were sampled while quietly standing participants were subjected to a random continuous EVS signal (peak-to-peak amplitude = ±3 mA). The relationship between EVS input and motor output was characterized in both the frequency (coherence) and time (cumulant density) domains. When head orientation was rotated in yaw from left to right, the biphasic cumulant density function was inverted for all muscle (EVS-EMG) and whole-body (EVS-AP forces) balance responses. When vision was occluded, the EVS-EMG and EVS-AP forces coherence function amplitude increased at low frequencies (
Databáze: OpenAIRE