Developing visual systems and exposure to virtual reality and stereo displays: some concerns and speculations about the demands on accommodation and vergence

Little is known about the developmental plasticity of the vergence and acco mmodative systems, an important issue since abnormalities can lead to visua l problems, e.g. strabismus. One way of artificially altering the links bet ween accommodation and vergence is to vary the stimulus to vergence while f ixing the accommodative stimulus, as is found in virtual reality displays. While it would be of interest to study developmental plasticity in this sit uation, since many children are exposed to games machines which use this ar rangement, no studies to date have tackled this issue. There is, however, s ome indication that long-term VR viewing in adults can lead to visual probl ems. It seems important to determine the safety of these systems for the de veloping human visual system before they come into common use. In this pape r, adaptation of the accommodation and vergence systems and the effect of V R viewing in adults is discussed. The sparse literature on adaptation in ch ildren is then reviewed, and suggestions made for approaches that would enh ance our knowledge of plasticity of accommodation and vergence in children. (C) 1998 Elsevier Science Ltd. All rights reserved.