Where do glasses fit into this?

In some instances your student is under a great deal of stress trying to perform sustained near-centered visual tasks such as reading. Besides the difficulty of the actual work you are assigning, one of the factors contributing to this stress may be an inability to focus their visual system at near. As we shift focus of our eyes from distance to near we have to supply about 2.50 diopters of accommodation ("focusing power"), a bit more so at the closer working distances that are representative of most children. Stress-relieving lenses are glasses designed to take some of the load off of the accommodative system. On average, these lenses reduce the amount the eye has to change focus by about 40%. This has the dual effect of helping the child stay on task for a longer period of time before their visual concentration begins to deteriorate as well as allowing them to stay further away from their close work, thus reducing the on-going demand on the accommodative mechanism.

During the course of treatment the role of the lenses often changes. Whereas at first they helped to maintain a good working distance and helped the child concentrate better, later on they take on more of a role in the prevention of the development of nearsightedness. You may have noticed that more of your excellent students are nearsighted and wear glasses or contact lenses to see clearly at distance. There are links between doing large amounts of sustained close work in people who are goal-oriented and detail-oriented and the development of nearsightedness or myopia. You may have also noticed fewer of those children with learning problems wearing glasses. Once the vision therapy has helped the child acquire the visual abilities necessary to learn and once they begin applying themselves in school they become at-risk to development of nearsightedness. The stress-relieving lenses help to prevent this.