Affiliations: [a] Department of Neurology, Case Western Reserve University, Cleveland, OH 44106, USA | [b] Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44106, USA | [c] Department of Neuroscience, Case Western Reserve University, Cleveland, OH 44106, USA | [d] Optometry, Veterans Affairs Medical Center and University Hospitals, Case Western Reserve University, Cleveland, OH 44106, USA
Note: [*] Correspondence to: R. John Leigh, M. D., Department of Neurology, University Hospitals, 11100 Euclid Avenue, Cleveland, OH 44106-5000, USA. Tel.: +1 216 421 3224; Fax: +1 216 421 3040; E-mail: rjl4@po.cwru.edu
Abstract: The goal of this study was to investigate the influence of light, without retinal slip information, on the ability to generate eye movements to compensate for head rotations. Subjects were rotated sinusoidally at 1.0, 2.0 or 3.0 Hz at a peak velocity of 30 deg/sec while they: 1) performed mental arithmetic in darkness; 2) attempted to view the remembered location of a stationary target in darkness; 3) attempted to view the remembered location of the stationary target through translucent contact lenses that allowed the passage of light but did not provide any target information (ganzfeld stimulus); 4) directly viewed the illuminated stationary target. The gain of compensatory eye movements was least while subjects viewed through the translucent contact lenses (median = 0.76), intermediate while subjects either performed mental arithmetic in darkness (median = 0.84) or attempted to view the remembered location of the target in darkness (median = 0.84), and greatest if they actually viewed the target (median = 0.95). Our findings suggest that factors other than light alone account for the increased gain of compensatory eye movements that occurs when subjects view rather than imagine a stationary target.
Keywords: VOR, visual-vestibular, ganzfeld, oculomotor, human
