[Psychological studies on accommodation of the eye]

Psychological studies on accommodation are reviewed on the following subjects: (1) subjective and objective methods of measuring accommodation, and their related practical problems in visual experiments, (2) accommodative responses in the absence of an adequate visual stimulus (a resting point of accommodation or a dark focus), and the specific phenomena of night myopia, empty myopia and instrument myopia, (3) contribution of accommodation to the perception of depth and the influence of imagination or thinking of distance on accommodation, (4) unsettled problems on accommodation in the three domains of myopia mentioned above, and the prospect of research in the future, and (5) a description of the results of psychological studies on accommodation that are applied to the establishment of an optimal condition of visual environment.