The Fatigue of Accommodation as Registered by the Ergograph

Abstract

So, too, the tics of childhood, representing purposes as they do (that is, compromise defense reactions of the simplest types) are trarfsitory. Like many other ailments, unless the physician acts quickly enough, children's tics may have a disconcerting way of vanishing without the aid of recognized therapeutic measures.

Visual Discomfort and Objective Measures of Static Accommodation

“…5,6,11,12 Results were mixed. For example, during a 15-min near work task that required sustained accommodation, Berens and Stark 12 found 30.8% of the office workers they tested showed a decrease in accommodative amplitude, 28.7% showed an increase, and 40.5% showed no change.…”

Accommodative dysfunction

“…A number of investigators have studied fatigue of accommodation using an ophthalmic ergograph (Berens and Stark, 1932 a;Berens, 1929;Howe, 1916). Berens and Stark (1932 b) found that 69% of a group of asthenopic subjects showed no evidence of fatigue of accommodation over a 15 minute period of time.…”

“…It is not simply an additional sign of insufficiency of accommodation as suggested by Duane (1916). Howe (1917) had delineated several varieties of fatigue based on the response of the subject's accommodative system while using the ergograph. Hofstetter (1943) has provided a review of literature concerning fatigue of accommodation.…”

“…In particular, overall debilitation and fatigue (Howe, 1917), poor lighting conditions Ferree, 1914), myasthenia gravis (Manson and Stern, 1965) and a low oxygen tension in the air due to high altitude or a rebreathing apparatus (Berens and Stark, 1932 b;Wilmer and Berens, 1918) have been noted to commonly produce fatigue in the accommodative system.…”

Accommodation fatigue and dark focus: The effects of accommodation-free visual work as assessed by two psychophysical methods

“…Several studies, some of them very old, frequently are cited as evidence that close work leads to such near-point recession (e.g., Berens & Sells, 1944;Berger & Mahneke, 1954;Ferree, 1913Ferree, , 1914Fitzpatrick & Hansen, 1973;Howe, 1916). Others have presented contrary evidence (e.g., Berens & Sells, 1950;Berens & Stark, 1932;Heaton, 1966;Lancaster & Williams, 1914).…”