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As part of an extensive investigation of the underlying variables in complex perceptual-motor performance, 35 male subjects were given practice under usual conditions on a Koerth-type pursuit rotor, and several days later practiced on the same unit at a slower speed with mirror-vision. The speed of the rotor for conventional direct-vision performance was 60 r.p.m. and for mirror-vision was 15 r.p.m. For direct-vision, the lengths of the work and rest periods were 10 and 20 sec., respectively, and for mirror-vision, 30 and 30 sec. Thirty trials of conventional practice were given, with a two minute break after trial 15. The number of mirror-vision trials was 40, with two-minute breaks after trials 10, 20, and 30. The lengths of the work and rest periods, the number of trials, and the speeds of rotation were adjusted so as to make the tasks about equally difficult and thus lead to approximately the same proficiency of performance throughout practice, as judged by per cent of time on target. The slow speed of rotation for the mirror-vision task was especially necessary. The purpose of this paper is to present performance curves for the two learning situations, to summarize information on reliability, and to indicate the strengths of the relationships between performance measures for the two tasks at comparable points during practice.

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Journal Title

Proceedings of the Iowa Academy of Science





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©1953 Iowa Academy of Science, Inc.



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