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MAKING MATHEMATICS AND SCIENCE ACCESSIBLE TO BLIND STUDENTS THROUGH TECHNOLOGY

Lawrence A. Scadden, Ph.D. National Science Foundation Arlington, VA

Abstract

Modern technology provides increased access to math and science educational instructional materials, media, and laboratory activities for blind students. Five projects supported by the National Science Foundation are described. Widespread use of these technologies would increase the math and science literacy of blind students and open new employment opportunities.

Background

Students who are blind are often counseled away from math and science courses even when their abilities and interests suggest that these are appropriate subjects for them to pursue. Little systematic effort has been made to provide access to science and math for blind students. The National Science Foundation (NSF) supports research and demonstration projects designed to enhance access to science and mathematics for students with disabilities.

Statement of the Problem and Rationale

Many employment opportunities today require mastery of math and science, and this requirement will increase in the future. Without opportunities to engage in these studies, students are denied important career options that should be available to them. Students with disabilities have been seriously underrepresented in science and math education and later in careers in these fields. Numerous blind scientists and engineers are currently successfully employed in their chosen careers. Personal creativity and assertiveness commonly were essential ingredients in implementing solutions to barriers they encountered, but use of adaptive techniques and technologies often provided needed accessibility. Documentation and dissemination of the techniques and technologies that enhance accessibility to science and math education for students with disabilities is needed. The following paragraphs describe five technological innovations that are increasing access to math and science for students who are blind.

Design, Development, and Evaluation

Access to mathematics. The six-dot braille code permits formation of 63 combinations of dots while higher-level mathematics is comprised of hundreds of different characters and functions. Standard braille notation for higher-level mathematics requires that multiple braille characters combine to represent most of these symbols. The presentation of equations commonly require several lines eliminating the possibility of retaining the customary, intuitive spatial layout of printed equations. Researchers have combined braille letters and numbers with raised-line math symbols preserving the spatial format of math equations(1). This technique, called "dotsplus," transforms the visual layout contained in an electronic document to a tactile layout. The dotsplus raised-line symbols are larger by a factor of approximately 2.5. These include most of the mathematical and scientific symbols. The document is printed by a modified wax-jet printer that produces tactile images, or it can be printed on a special "swell" paper using almost any standard printer. The swell paper is then heated causing the black portions to swell. Dotsplus documents cannot be printed directly from most computer files; they require use of high-level computer files. Dotsplus documents can presently be printed from LaTeX files and from some graphics-based word processor files. Dotsplus was first evaluated informally by over 50 blind scientists and mathematicians from around the world resulting in nearly unanimous endorsement of the technique. Additional evaluation is underway after advanced math textbooks were prepared for several blind students in dotsplus format. Widespread use of dotsplus will require availability of more math and science texts in high-level markup languages and the introduction of good quality, commercial wax-jet printers and/or lower priced swell paper.

High-level computer files can also be used to produce auditory displays of higher-level math equations. These computer files (produced by "markup" languages) contain "tags" that identify functions and spatial layout of the file elements. Many publishers use these high-level computer files for preparing scientific texts. The AsTeR (Audio System for Technical Readings) computer program2 uses these files to present mathematical and scientific information to blind users through an audio format. The audio formatting presents the information and structure using both synthetic speech and non-speech sound cues. A listener can change how specific information structures are rendered and review them selectively by using many browsing commands. Efforts to port AsTeR to personal computers are nearing fruition. This combined with an increased availability of electronic texts marked up in La)TeX or other high- level computer language should permit widespread use of AsTeR by blind math and science students and professionals.

Multimedia presentation of the calculus. Mastery of the calculus is critical to students desiring to study science and engineering because it is fundamental to most advanced courses in these disciplines. The calculus often presents a serious barrier to blind students because the typical calculus course relies heavily on a substantial use of graphical components. Researchers are developing text materials and a multimedia environment to provide blind students enhanced access to the calculus(3). The project uses course content from a self-paced mastery course in calculus developed at Carnegie-Mellon University, and blind students use new multisensory media to present the course materials. Audio-tactile displays are prepared and programmed to be presented by the touch- sensitive NOMAD (TM), an audio-tactile tablet. Graphics are embossed on a soft plastic sheet that also contains a tactile grid. The more important details of the graph are presented in higher relief to give tactile expression to their varying importance. A round button is located at the base of each vertical grid line. When the button is pressed, the NOMAD verbalizes the x-coordinate of that line. Similar buttons are located along the left margin to identify the y-coordinates of the horizontal gridlines. A row of diamond-shaped buttons located along the upper right margin of the graphic announce associated key words from the text. Features on the graphic can be programmed to be spoken when pressure is applied to that location on the NOMAD's surface. Three levels of information can be programmed to be spoken. Blind calculus students are assisting in the project by evaluating the instructional materials at each stage of their development.

Three-dimensional tactile models. Three-dimensional computer graphics are now commonly used in many disciplines to display physical phenomena and mathematical data. Access to information displayed in three-dimensions has been difficult for blind students, and analogous tactile models have been difficult to produce. Recently, an innovative technique, laser stereolithography, has been used to produce tactile molecular models for blind chemists and chemistry students(4). This rapid prototyping process is used to produce three-dimensional plastic models from images created in computer aided design (CAD) programs. A computer-controlled laser is used to cure and solidify a light- sensitive, liquid polymer in a shape of an image produced by the CAD program. The process accurately produces intricate structures. Surface textures are modified to enhance tactual identification of atom types. Informal evaluation was first provided through regular use of the process by a blind chemist in his research. A more formal evaluation is currently underway in the Washington State School for the Blind.

Laboratory measurements. Independent measurement of laboratory experiments have traditionally been difficult for blind students. Since 1977, researchers at East Carolina University have attempted to develop instrumentation that would provide this independence for blind science students(5). Recent introduction of commercial science kits for school laboratories has simplified these efforts. Computers are made fully accessible to blind students with speech synthesizers, sound cards, and special software; and they become robust laboratory tools when connected to appropriate laboratory sensor probes provided in the new science kits. The East Carolina University researchers have now developed software that permits blind students to perform independent data acquisition and analysis for many types of scientific experimentation. Using a "talking, whistling, musical, large text laboratory work station," blind students can independently measure temperature, pH, mass, light intensity, distance, and properties of electrical circuits. Rising and falling pitches enable blind students to locate peaks and other qualitative features while the speech synthesizer verbalizes the quantitative measurements. Additional software programs are being developed that will provide independent performance of titrations, infrared and visible spectrometry, gas chromatography, and high- performance liquid chromatography.

Described video. Acquisition of the visual content on videos and films has always been a problem for blind "viewers." This becomes a potentially serious issue when the videos and films have an educational purpose. Auditory descriptions of visual scenes and activities traditionally have been available to blind people only from other viewers. For several years, the WGBH Education Foundation has been providing audio descriptions through its Descriptive Video Service (DVS) (R) on several dramatic series broadcasted by the Public Broadcasting Service (PBS). A three-year grant was awarded to the WGBH Education Foundation to study the value of describing science programs for blind viewers. The American Foundation for the Blind (AFB) conducted a rigorous evaluation of the value of audio description of science programs with over 100 blind viewers. Results of the study clearly demonstrated that blind viewers understand and retain information from science videos far better when audio descriptions are provided(6).

Conclusion

Modern technology is providing increased independent access to, and performance in, math and science education. Broad dissemination of these techniques and technologies should significantly increase the representation of blind students enrolled in science and math curricula and pursuing careers in these fields.

References

1. Barry, W.A., J.A. Gardner, and R. Lundquist. (1994). Books for blind scientists: The technological requirements of accessibility. Information Technology and Disabilities Journal, Refereed Journal of EASI [Online], Available e-mail: listserv@sjuvm.stjohns.edu Message: get ITD V01N4 ARTICLE8.

2. Raman, T.V. (1992). An Audio View of La(TeX) Documents. Proc. TeXUsers Group, 13, 372-379.

3. Blank, A., K.L. Gourgey, and M.E. Kress. (1994). A. graphical calculus course for blind students. Information Technology and Disabilities Journal, Refereed Journal of EASI [Online], Available e-mail: listserv@sjuvm.stjohns.edu Message: get ITD V01N4 ARTICLE3.

4. Skawinski, W.J., T.J. Busanic, A.D. Ofsievich, V.B. Luzhkov, C.A. Venanzi, and T.J. Venanzi. (1994). The use of laser stereolithography to produce three-dimensional tactile molecular models for blind and visually impaired scientists and students. Information Technology and Disabilities Journal, Refereed Journal of EASI [Online], Available e-mail: listserv@sjuvm.stjohns.edu Message: get ITD V01N4 ARTICLE6.

5. Lunney, D. (1994). Assistive technology in the science laboratory: A talking laboratory work station for visually impaired science students. The Student Advocate, National Alliance of Blind Students, David Sass, ed., Volume XII, No. III.

6. Schmeidler, E. and C. Kirchner. (1995). Adding Audio Description to Television Science Programs: A Study of Impact on Legally Blind Viewers, American Foundation for the Blind, New York: Final Report for NSF Grant # ESI-9253447 on subcontract from the WGBH Education Foundation.

Lawrence A. Scadden, Ph.D. Senior Program Director Program for Persons with Disabilities National Science Foundation 4201 Wilson Blvd., Room 815 Arlington, VA 22230 Phone: (703) 306-1636 Fax: 703-306-0423 E-mail: Lscadden@nsf.gov