Teaching Science To Blind Students

When we teach children with sight to read textbooks containing complex ideas and mathematical equations, we teach them to read actively: that requires rereading, referring back to the text, and creating a visual representation of the information so that they can synthesize and remember it. Reading for a sighted person is an active process, but for blind students, it is the opposite. Blind students have traditionally learned by reading braille texts, or voice synthesizers that essentially read the information out loud to them. These synthesizers are more prevalent in science or technical classes because braille texts are so big and bulky. Books on tape have long been accepted for both sighted and blind communities, but they only active participation available is rewinding or fastforwarding a long the chronological timeline. Textbooks and technical writing are not at all suited to being listened to with only rewind/fastforward capabilities because they are so complex and information is often not exclusively sequenced chronologically.

Translating an already large textbook into braille (which can involve an active reading process) would probably mean tripling its size. The challenge with synthesizers is that they often do not approximate th eprosody of normal human speech which makes it hard for students to listen and retain the information. Moreover, they do not present the opportunity to easily scan back, re-read (re-listen) or give any information as to how to visualize the information. Complex information such as equations, scientific or technical documents are therefore very hard to synthesize or internalize. This means that blind people are often prevented from accessing a great deal of technical material.

Research at Dublin City University is currently exploring ways that prosody can help signify the symbols in equations that it woudl be really confusing to read out loud such as parenthesis, or the multiplication symbol. BY inserting a series of timed pauses as a code for these markings, blind students can understand and begin to visualize an equation like = (2x3)-2 without having to hear, remember, parse, and synthesize a monotone computerized reading of, "y equals parenthesis two times three parenthesis subtract two." Using a combination of pauses and alterations in rate of speaking, the speaker (or computer generated speaker) can signify different visual symbols.

Science is a discipline in which it is often vitally important to be able to see the diagrams and graphs. Students who are blind can rely on tracing outlines of raised images with their fingers, or verbal descriptions of things, but the same researchers at DCU are experimenting with sound descriptions instead. By varying frequencies of sound there can be sonic representations of graphs and charts. By using a combination of raised pictures and accompanying sound signals a multi-modal approach can provide much richer sources of information that simply tracing an outline or hearing a verbal description.

Blind students in the classroom develop impressive skills in synthesizing information just from speech, but the lesson drawn from this research is that it is important to be consistent in the way speech is expressive, and strategically vary auditory clues to signify the details and shadings that would have been apparent if the information was taking in visually. Even without the technology or training to do this formally, teachers can be aware of how they use their voices to explain or describe visual information. They can also develop shortcuts or shorthand to convey things like symbols or visual information that might confuse or complicate the auditory information for a blind listener.

: Fitzpatrick, Donal: "Teaching Science Subjects to Blind Students" 7th IEEE international conference on Advanced Learning Technologies. 2007 http://csdl2.computer.org/comp/proceedings/icalt/2007/2916/00/29160917.pdf:

posted by Rachael Gabriel