FIGURE 5.1 Testing infants' visual acuity Paddles like those depicted here can be used to assess young infants' visual acuity. Two paddles are shown to the infant simultaneously, one with stripes and one in plain gray. If the infant can detect the contrast difference between the black and white stripes, the infant's gaze should, because of infants' preference for a patterned visual field over a plain one, become oriented toward the striped paddle. The ophthalmologist or researcher presents the infant a succession of paddles with increasingly narrow stripes, with increasingly narrow gaps between them, until the infant can no longer distinguish between the striped paddle and the plain gray one. The degree of grating on the last paddle discriminated provides an indication of the infant's visual acuity.
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