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Performance on the Star Discrimeter has several interesting features, the most important of which have to do with retention and transfer. This paper summarizes recently obtained data and offers a tentative explanation. A brief description of the apparatus and the task that is learned should first be given. The Iowa model of the Discrimeter is basically like the original unit developed at Northwestern University (1). The subject learns to move a vertical wobble-stick rapidly into one of six horizontal channels, depending on the color of the light that appears on a stimulus panel 30 inches away at eye level. The six channels, equally spaced 60 degrees apart, radiate out from a central opening through which the wobble-stick protrudes. When a correct channel is entered, a stepping switch is activated to bring up a new color. The number of channels correctly entered per trial period is recorded, as is the number of errors. Each channel has a length of 31/4 in., and each one has two microswitches placed ½in. and 21/4 in. from its entrance. This provides for counting both shallow and deep errors. A large number of different tasks may be obtained on the Discrimeter by changing the interconnections between the six colored lights and the six channels.

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Proceedings of the Iowa Academy of Science





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©1954 Iowa Academy of Science, Inc.



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