Incised Grids: Enhancing the Readability of Tangible Graphs for the Blind

Abstract

The transformation of a graphic display into tangible form for blind persons is usually achieved by raising the entire image above the surface. In the case of tangible line graphs, this format causes readability problems by degrading figure-ground (data-curve/grid) differentiation. This study assessed the feasibility of a new design format involving both raised and incised elements in the same display. The results from 24 blind students in grades 4 through 7 indicated that an incised-grid/raised-data-curve format significantly improves graph-reading performance relative to a raised-grid/raised-data-curve format. The importance of designing displays in ways that are compatible with the perceptual-motor capabilities of blind persons is discussed.

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References

Barth, J. L. The development and evaluation of a tactile graphics kit. Journal of Visual Impairment and Blindness, 1982, 76, 269–273.

Barth, J. L. Factors affecting line tracing in tactile graphs. Journal of Special Education, 1983, 17, 215–226.

Bentzen, B. L. , and Peck, A. F. Factors affecting traceability of lines for tactile graphics. Journal of Visual Impairment and Blindness, 1979, 73, 264–269.

Berla, E. P. Tactile scanning and memory for a spatial display by blind students. Journal of Special Education, 1981, 15, 341–350.

Berla', E. P. , and Butterfield, L. H. Tactual distinctive features analysis: Training blind students in shape recognition and in locating shapes on a map. Journal of Special Education, 1977a, 11, 335–346.

Berla, E. P. , and Butterfield, L. H. Tactile political maps: Two experimental designs. Journal of Visual Impairment and Blindness, 1977b, 71, 262–264.

Berla, E. P. , Butterfield, L. H. , and Murr, M. J. Tactile political map reading by blind students: A videomatic behavioral analysis. Journal of Special Education, 1976, 10, 266–276.

Berla, E. P. , and Murr, M. J. Psychophysical functions for active tactual discrimination of line width for blind children. Perception & Psychophysics, 1975, 17, 607–612. (a)

Berla, E. P. , and Murr, M. J. The effects of tactual noise on the location of point symbols and tracing a line on a tactile pseudomap. Journal of Special Education, 1975, 9, 183–190. (b)

10.

Geldard, F. A. The human senses (2nd ed.). New York: Wiley, 1972.

11.

Gill, J. M. Method for the production of tactual maps and diagrams. American Foundation for the Blind Research Bulletin, 1973, No. 26, 203–204.

12.

James, G. A. Kit for making raised maps. New Beacon, 1975, 59, 85–90.

13.

James, G. A. , and Armstrong, J. D. An evaluation of a shopping centre map for the visually handicapped. Journal of Occupational Psychology, 1975, 48, 125–128.

14.

Kahneman, D. Attention and effort. Englewood Cliffs, NJ: Prentice-Hall, 1973.

15.

Kirchner, C.

Non-text reading matter: How should it be presented?

Journal of Visual Impairment & Blindness, 1979, 73, 329.

16.

Lederman, S. J. , and Campbell, J.I. Tangible graphs for the blind. Human Factors, 1982, 24, 85–100.

17.

Nolan, C. Y. Relative legibility of raised and incised tactual figures. Education of the Visually Handicapped, 1971, 3, 33–36.

18.

Nolan, C. Y. , and Morris, J. E. Improvement of tactual symbols for blind students: Final Report. Louisville, KY: American Printing House for the Blind, 1971.

19.

Schiff, W. , Kaufer, L. , and Mosak, S. Informative tactile stimuli in the perception of direction. Perceptual & Motor Skills, 1966, 23, (Monogr. Supplement 7).

20.

Wiedel, J. W. , and Groves, P. A. Tactual mapping: Design, reproduction, reading, and interpretation: Final Report. College Park, MD: University of Maryland, 1969.