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 CSD 5230

Communication Symbols

General Terms

• Symbol - is "something that stands for or represents something else" (Vanderheiden & Yoder, 1986).
• Referent - the "something else" that a symbol represents is called its referent.
• Iconicity - refers to the continuum that describes symbols by ease of recognition.
• Transparent - At one end of this iconicity continuum are transparent symbols, which visually resemble their referents and thus are high in guessability, and at the other end are opaque symbols, whose visual relationships to their referents are not obvious and may be quite arbitrary.
• Translucent - In the middle of the iconicity continuum are translucent symbols, which are not readily guessable without additional information. Translucent symbols are often described in terms of their learnability.
• Aided - symbols require some type of external assistance such as a device for production. Examples of aided symbols include real objects and black and white line drawings.
• Unaided - symbols require no external device for production. Examples of unaided symbols include facial expressions, manual signs, natural speech and vocalizations.
• Pictograph represents the meaning of a word or concept through a picture; e.g., a photograph, picture or line drawing of a house to represent house.
• Ideograph represents an idea related to the word; e.g., a drawing of a heart to represent love or emotion.
• Arbitrary is one to which meaning is assigned; e.g., Blissymbols uses the symbol / to represent the.

Aided Symbols

• Tangible Symbols refer to two or three dimensional aided symbols that are permanent, manipulable with a simple motor behavior, tactually discriminable, and highly iconic. Symbols that can be discriminated on the basis tangible properties (shape, texture, consistency).
• Real Objects - may be identical, similar to, or associated with their referents. For example,
• Identical Symbol - "brush your teeth" might be a toothbrush that is the same color and type as the individual's actual toothbrush.
• Similar Symbol - toothbrush of a different color and type
• Associated Symbol - might be a tube of toothpaste, container of dental floss, wrappers from fast food
• Miniature Objects may be more practical than real object symbols in some situations buy need to be selected carefully. May be difficult to recognize by intellectually disabled.
• Partial Objects involve those that are large. For example, top of spray bottle of window cleaner may represent washing windows.
• Artificial Associated And Textured Symbols
  • For example, a wooden apple may be attached to a cafeteria door and a similar apple could be used as the symbol. Textured symbols may logically or arbitrarily associated with their referents. A logically associated textured symbol could be piece of spandex material to symbolize a bathing suit. Alternatively a square velvet could be selected to represent a favorite snack.

Representational Symbols include 2 dimensional symbols.

• Photographs
  • Mirenda & Locke (1989) - Cognitively delayed matched color photographs to referents more accurately than black and white photos
  • Sevcik & Romski,(1986) - Cognitively delayed matched black and white photos to referent more accurately than line drawings
  • Color versus B/W, no data
  • Issue of context not clear - Dixon (1981) found that students with severe disabilities were more able to associate objects with their color photographs when the photographic objects were cut out than when they were not. Reichle (1991) suggested that the context in which a photograph appears may affect an individual's ability to recognize it, for example, a photograph of a watering can may become more recognizable when it appears next to a plant.
• Line Drawings
  • Picture Communication Symbols (PCS) - widely used system of 1800 simple line drawings. PCS can be purchased in a variety of formats, including stamps, symbol books and software.
  • Picture Exchange System - Single Subject Design Research
  • Rebus Symbols - A rebus is a picture that visually or nominally represents a word or a syllable. For example, a picture of a knot could be used to symbolize either "know" or "not.
  • Picsyms (Dynasyms) is a logical system of visual-graphic symbols that were developed through work with young children who were unable to speak. 1800 symbols are available. New symbols can be created by following the generative rules that are include with the dictionary of symbols. Research indicate that Picsyms appear to be similar to or slightly more difficult than both PCS and rebus symbols and superior to Bliss.
  • Pictogram Ideogram Communication (PIC) Symbols - consists of 400 white on black symbols designed to reduce figure-ground discrimination difficulties. Have been used with severe disabled and autistic individuals.
  • Blissymbolics - System was developed to function as an auxiliary language for international written communication. It consists of a 100 basic symbols that can be used individually or in combination to encode virtually any message. The original system consisted of 1400 black and white symbols with written labels. New Bliss symbols are added annually by an international panel affiliated with Blissymbolics Communication International.
  • Enhanced Blissymbols - A Collection of Blissymbols are available that have been enhanced by pink line drawings cues. These enhanced Blissymbols are designed to remind the beginning user of the concepts that the symbols represent.
    • Major strength of Bliss - Principles and strategies for combining symbols enable expression of thoughts not on the communication board. The symbols are conceptually based and constructed using consistent, systematic rules.

Abstract Symbols Systems

• Yerkish Lexigrams resulted from a primate research project designed to develop computer based system for studying language acquisition in chimpanzees. The lexigrams are composed of 9 geometric forms used singly or in combinations of 2, 3, 4, to form symbols.
• Non SLIP (Non-Speech Language Initiation Program) symbols were predecessor to Yerkish lexigrams since they originated in early chimpanzee language work (Premack, 1971). Symbols are plastic or masonite chips that vary in color, shape and size and are accompanied on reverse side by printed English word meanings.

Orthography and orthographic symbols

• Traditional orthography refers to written characters used to transcribe a particular system (English alphabet, Chinese characters).
• Orthographic symbols is used to refer to aided techniques that represent traditional orthography, such as braille, Morse code, and phonemic symbols.
• Morse code is an international system that users series of "dits" (dots) and "dahs" (dashes) to represent letters, punctuation, and numbers. When used in AAC applications, code is transmitted via microswitches through a device called a emulator that translates it into orthographic letters and numbers.
• Braille is a tactile symbol system for reading and writing that is used by persons with visual or dual sensory impairments. Braille characters are formed by combinations of 6 embossed dots arranged within a "cell" of two vertical columns of three dots each. The characters represent letters, parts of words, or entire words.

Considerations in selecting symbols

• Openness - Traditional orthography is highly open because the user can express any item that can be spelled. In contrast, pictographs have more limited openness, since they do not provide access to any words or concepts beyond those displayed on the aid (with the exception of MINSPEAK). Ideographic and abstract symbols tend to be more open than those that use only pictures, since it is difficult to represent abstract concepts through pictures alone. The more open a symbol system is, the more abstract it is. Symbols must be chosen that will provide the openness the individual needs but that also are within his cognitive/linguistic abilities.
• Intelligibility - The ability of the symbol to be understood with no prior training. This depends on the output of the aid and the obviousness of the symbols.
• Electronic Aid - The need for the partner to understand the symbols depends upon the output produced (printed or spoken).
• Nonelectronic Aid - The obviousness of the symbols used is important. If a pictograph is used, the word or phrase corresponding to it should be printed above it because the meaning of the symbol may not be obvious to those unfamiliar with the system. A partner who is unable to read the word printed above the symbol must understand the specific system being used.
• Strategies - If a pictographic system is used that allows the user to create new words not displayed, printing the word corresponding to the symbols may not be of assistance. For example, in Blissymbols the word talk can be created by indicating action then mouth. In such a case, the partner would need to know the strategy.
• Amount of time to learn symbols - Time available to train the partner to learn symbols must be considered. If user communicating with unfamiliar partners or partners with little time available, then symbols easily intelligible to an untrained person must be used. Thus, with different partners, symbols from different sources may be used depending upon the partner's abilities.

Using one symbol set or system versus several

• Advantage of using a single set is that if many individuals in the immediate environment also use it, they will understand each others symbols and can communicate with each other. If a specific system is used, the user may be able to achieve maximum degree of openness by using the strategies and symbols consistently (rather idiosyncratic) rather than mixing various sets and systems.
• Disadvantage of using one source is that if a symbol from a particular set or system is too abstract for the user or not obvious enough for partners to understand, the individual may not be able to use it. If the set is limited in openness, the individual is limited in the ideas that could be expressed.
• Mixed - Thus hand-drawn pictographs or those collected from magazines and photos, prepackaged sets of pictographic symbols, and symbol systems can be combined. New symbols can be created incorporating ideas from different sources as well.