Tactual Distinctive Features Analysis: Training Blind Students in Shape Recognition and in Locating Shapes On a Map

Abstract

Two experiments were conducted to determine the effects of training blind students in shape recognition accuracy and speed and accuracy of locating shapes on a tactile map by using a distinctive features analysis strategy and line tracing. In Experiment 1, training significantly improved the shape-recognition performance of a group of 25 trained braille readers, as compared to a matched group of 25 untrained braille readers. In Experiment 2, 21 trained students (as compared to a matched group of 21 untrained students) showed a significant increase in the number of shapes located and a significant decrease in the average time to locate a shape on a tactile map. Results are discussed in terms of the critical importance of training blind students to be analytical, systematic, and complete in exploring tactile materials so as to ensure adequate development of their perceptual-conceptual abilities.A series of studies investigating the effects of stimulus parameters and methods of exploring shapes (Berld, 1972; Berla, 1974; Berld & Murr, 1972) found that tactual shape discrimination performance was quite poor by blind children in grades 1-6. Three, striking observations were made concerning the blind child's inspection of tactile shapes. First, many of the children failed to completely explore the entire tactile shape, and many inspected only a small portion of a shape. Second, the overwhelming majority of the students had no systematic method for exploring shapes. Third, some subjects did trace the entire shape, but did not appear to realize at what point on the shape they had begun tracing and at what point on the shape they had completed their tracing.

Angle Discrimination in Raised-Line Drawings

“…These findings can furthermore have implications for studies of the perception of raised-line drawings: if there are different exploration modes that are best for the assessment of different geometric features, it could be useful to instruct observers to use those particular modes. In tactile map reading, it has already been shown that training of exploration improves mapreading qualities (Berla and Butterfield 1977).…”

Design principles for tactile interaction

“…The system, called Weasel, uses PVC tactile overlays on an Intellikeys touchpad in conjunction with speech output and audio output. Results obtained from the close observation of users working with the system have been used along with existing psychological knowledge on interaction with raised lines [1,2,9], tactile symbols [3,7,11,12] and textures [6,8,10], to create a set of fundamental design principles for tactile interaction.…”

Tactile localisation: the function of active antennal movements in the crayfishCherax destructor

“…Very little, however, is known about the role and the patterns of movement in elucidating a spatial scene (cf. Davidson 1972;Berla and Murr 1974;Berla and Butterfield 1977;Hatwell 1978;Millar 1979;Lederman et al 1985).…”