Sigrid Diether showed that eyes can compensate refractive errors even in local retinal areas. For this experiment, the chickens were raised with hemi-field lenses. The observation argues against a role of accommodation in the control of eye growth by vision.

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In her second project, she has set up a large drum in which the chickens' visual acuity and contrast sensitivity can be measured.
The head rotation of the chicken while it follows the drifting gratings is quantified by an image processing software written in C++. She found that the chickens' contrast sensitivity increased while they were wearing translucent eye occluders which produce myopia. Contrast sensitivity was back to normal one hour after occluder removal. She also found that atropine shifts the contrast sensitivity curve to increased sensitivity at higher spatial frequencies.

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