The tactual identification of shapes for coding switch handles.

Three experiments concerning the tactual identification of 16 differently shaped lever-switch handles are described. A comparison of the "find" method (S searched through a set to find a particular handle) with the "learn" method (S learned to associate a number with each handle) showed moderate agreement in specifying the predominant confusions and measuring their extent. Change in handle size (from ?-in. to 3/8-in. diameter) had no effect on learning. Two subtests of ten handles selected so as to avoid the predominant confusions were more homogeneous than the original set of sixteen handles, and each subset was learned quickly. (PsycINFO Database Record (c) 2010 APA, all rights reserved)