Braille and AACS for Sensory Impairments
Visual Impairments: Braille Literacy
The Origins of Braille
Valentin Haüy (1795) founded the Institute of Blind Youth (IJC) in Paris and developed the first reading and writing system for the blind, using wooden blocks with carved letters. Later, Charles Barbier (1808) invented a nocturnal writing method based on a dot alphabet, enabling soldiers to communicate silently at night. Louis Braille (1809-1852), who lost his sight in childhood, was a student and later a teacher. He adapted Barbier’s method for people with visual impairments.
How Braille Works
Braille uses cells with a maximum of six dots, which is the most that can be perceived with a fingertip. These cells (2.5x5mm) have two columns and three rows of raised dots. Each dot is assigned a number.
- Braille allows for the representation of letters, numbers, punctuation, musical notation, and mathematical symbols.
- It utilizes 64 distinct cell combinations.
Reading and Writing in Braille
Dots are embossed (raised) using a punch (punzón) and a Braille slate (regleta or pauta). This slate consists of two joined plastic or metal layers. The bottom layer has small rectangles, each with six dots, while the top layer has cells corresponding to these rectangles.
A sheet of paper is placed between the layers. Dots are punched from right to left. The paper is then flipped to read from left to right.
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Prerequisites for Learning Braille
- Conceptual Knowledge:
- Understanding of spatial concepts: up, down, right, left, in front, behind.
- Quantity concepts: many, few, more, less, 1-10.
- Qualitative concepts: same, different, similar; different fabrics; thickness.
- Procedural Knowledge (Skills):
- Using index and middle fingers to follow dotted lines.
- Discriminating the number of dots on paper.
- Turning pages one by one.
- Punching holes in paper.
Technical Aids for Braille
- Non-Electronic:
- Punches and slates for manual writing, adapted to age and manual dexterity.
- Pre-reading books or books with tactile stimulation for tactile discrimination.
- Tactile books with raised pictures.
- Braille books.
- Electronic Aids:
- Sagem printer: Allows typing on a standard keyboard and printing in Braille (no Braille knowledge required).
- Perkins Brailler:
- Six keys (one for each dot), a space key, a backspace key, and a line feed key.
- Each character is typed by pressing the corresponding dot keys simultaneously.
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Auditory Impairments: AACS
- Cochlear Implants: The most frequent solution. A surgically implanted device simulates the function of the cochlea. While beneficial, it’s not identical to natural hearing, requiring adaptation by the user.
- Intervention in Language: Augmentative and Alternative Communication Systems (AACS):
- Alternative systems replace spoken language.
- Augmentative systems support spoken language; they do not replace it.
Types of AACS
- Sign Language: A naturally developed language with its own grammar and rules, varying geographically and culturally, similar to spoken languages.
- Bimodal: An artificial system, more universal than sign language but still influenced by cultural factors. It primarily focuses on vocabulary, lacking a formal grammar.
- Manual Alphabet: Uses handshapes to represent letters of the alphabet. Can be one-handed (e.g., Spanish) or two-handed (e.g., English).
- Cued Speech: Uses handshapes near the mouth to represent syllables phonetically, not orthographically. Example: Pa-pá; Ca-sa; Que-so; Ce-ni-ce-ro.