Abstract
Efferent circuits within the nervous system carry nerve impulses from the central nervous system to sensory end organs. Vestibular efferents originate in the brainstem and terminate on hair cells and primary afferent fibers in the semicircular canals and otolith organs within the inner ear. The function of this efferent vestibular system (EVS) in vestibular and motor coordination though, has proven difficult to determine, and remains under debate. We consider current literature that implicate corollary discharge from the spinal cord through the efferent vestibular nucleus (EVN), and hint at a potential role in overall vestibular plasticity and compensation. Hypotheses range from differentiating between passive and active movements at the level of vestibular afferents, to EVS activation under specific behavioral and environmental contexts such as arousal, predation, and locomotion. In this review, we summarize current knowledge of EVS circuitry, its effects on vestibular hair cell and primary afferent activity, and discuss its potential functional roles.
Highlights
The flow of information through the nervous system can be viewed as relatively simple
The EVS has been implicated in efference copy generated from spinal cord circuitry during locomotion, while participation in vestibular plasticity and compensation has been suggested
Combining monosynaptic tracing technologies with electrophysiological recordings could further investigate the role of the EVS in corollary discharge signaling in mammals
Summary
The flow of information through the nervous system can be viewed as relatively simple. The functional role of most efferent systems in the nervous system has been characterized. In the vestibular system a conclusive functional role in mammals has yet to be confirmed.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
