Vision accommodation refers to the focusing ability of the eye. When an object is distant, light rays that enter our eye and allow us to see it are almost parallel. However, a closer object causes light rays to diverge, causing the eye muscles to tighten to keep the object in focus. When you're young, these muscles are quite elastic and can quickly accommodate at different distances. These muscles lose elasticity with age, however, resulting in decreased ability to focus on near objects (presbyopia). You will probably notice when this begins to happen, but here are a few simple ways to easily test vision accommodation.
Test your vision accommodation by checking your reading distance. Normal reading distance is about 14 inches (35 cm). Once you reach your 40s, you will likely find it harder and harder to focus on near objects, such as words in a book or magazine. You may find yourself holding your reading material at arm's length and/or pulling your head back in order to see words more clearly, a sure sign of decreased vision accommodation.
Test your visual accommodation by turning on a light. Reading or doing close work with appropriate lighting is always a good idea, but with presbyopia, normal lighting may not be enough for close focus work. The reduced visual accommodation of aging is even worse in low light. If you can focus on near objects much more easily in bright daylight or with direct light, your visual accommodation may be decreased.
Test your vision accommodation with store-bought reading glasses. Presbyopia, or loss of vision accommodation with age, occurs gradually and worsens gradually. You may be able to correct the problem for a while with simple reading glasses available over-the-counter in varying degrees of magnification.
Test your visual accommodation with a professional eye exam. See your optometrist or doctor. In your activities of daily living, you may notice that your vision is changing, but only an eye exam by a qualified professional, with appropriate equipment, can determine the extent of change and the degree of vision correction needed.