Role of extraocular muscle proprioception

Extraocular muscle proprioception has been debated for a long time and has been an unfailingly interesting field. In many studies of vision, the Spatial perception is considered to be built by not only direct retinal image, but also by other various data points including extraocular muscle proprioception, efference copy, stereopsis, and convergence. Visual movement assessment with information of efference copy (outflow) and afferent feedbacks from proprioceptors (inflow) is considered to exist in the central nervous system. A consensus regarding the existence of neural pathways for, and the necessity and role of extraocular muscle proprioception have not yet been achieved because of the obvious existence of a more obvious signal outflow of efference copy, which arguably obviates the need for other datasets for visual perception. Although, evidence supporting the existence of possible proprioceptors (muscle spindles, palisade endings or innervated myotendinous cylinders) in histological studies, and neural activity related to extraocular muscle proprioception in neurophysiological studies have been reported, their functional roles remain unclear. Recently, the possibility of its influence on oculomotor control, convergence, and divergence has been reported. Moreover, extraocular muscle proprioception is notable for its potential role in elucidating the pathogenesis and treatment of strabismus.