Tangible symbols are a type of augmentative and alternative communication (AAC) that uses objects or pictures that share a perceptual relationship with the items they represent as symbols.
A tangible symbol's relation to the item it represents is perceptually
obvious and concrete - the visual or tactile properties of the symbol
resemble the intended item. Tangible Symbols can easily be manipulated
and are most strongly associated with the sense of touch. These symbols
can be used by individuals who are not able to communicate using speech
or other abstract symbol systems, such as sign language.
However, for those who have the ability to communicate using speech,
learning to use tangible symbols does not hinder further developing
acquisition of natural speech and/or language development, and may even facilitate it.
Definition
The term tangible symbols was first developed by Charity Rowland and Philip Schweigert,
and refers to two-dimensional pictures or three-dimensional objects
used as symbols to convey meaning. The items are termed "tangible"
because they are concrete items that can be manipulated by the user and
communication partner. Symbols can be used individually or combined with
other symbols in order to create new messages. Tangible symbols are
used as a means of communication for individuals who are unable to
understand or communicate using abstract systems, such as speech or sign language.
Properties of tangible symbols include permanency, capacity to be
manipulated by both the user and the communication partner, and an
obvious relationship between the symbol and the referent. They can
represent items, people, activities and/or events, and look or feel
similar to what they refer to. For example, a cup can be used as three-dimensional tangible symbol to represent the action: "drink".
A photograph of a cup can be used as a two-dimensional tangible symbol
to also represent the action : "drink". Two- and three-dimensional
symbols are used to fit the cognitive and sensory abilities of the
individual, as well as the individual's unique experiences.
Rowland and Schweigert use the term tangible symbols to refer to
conceptually tangible items like two-dimensional pictures or
three-dimensional objects.
However, other authors, such as Beukelman and Mirenda, use the term to
exclusively describe three-dimensional physical objects that display
concrete properties such as shape or texture.
According to Rowland and Schweigert, "for some individuals, the
use of tangible symbols may be used to bridge the gap between gestural
communication and the use of formal language systems. For others,
tangible symbols may represent an ultimate level of communicative
competence."
| Level of Communication | Means of Communication |
|---|---|
| Presymbolic | Body and limb movements, Gestures, Vocalizations |
| Concrete Symbolic | Symbolic gestures and vocalizations, Tangible Symbols: Objects (three-dimensional) & Pictures (two-dimensional) |
| Abstract Symbolic | Speech, Sign Language, Printed Language, Braille, Abstract shapes, Abstract graphics |
History
Historically, objects and pictures have frequently been used as communication devices.
Many authors have also used picture symbols, such as line drawings and
photographs to develop language in individuals with little or no speech
and/or cognitive disabilities. Tangible symbols emerged from Van Dijk’s work in the 1960s using objects as symbols to develop language in deaf-blind children.
In turn, Van Dijk’s work was based on the concept "symbol formation"
developed by Werner and Kaplan (1963), who theorized that "symbol
formation" referred to the process of developing language by creating
symbols in our minds.
Types of tangible symbols
Rowland and Schweigert propose that tangible symbols can be divided into hierarchical categories, ranging from most concrete to most abstract symbols:
- Identical objects are real items that are equal to their referent and are the most concrete type of tangible symbol. An example includes using a toothbrush to represent "brush your teeth". Beukelman and Mirenda includes in this category miniature objects: items that are smaller than what they symbolize, such as having a small toy toilet indicate "toilet".
- Partial/associated objects refers to a portion of the object they represent, and therefore are less concrete than identical objects. For example, a shoelace would symbolize "shoes".
- Symbols with one or two shared features have a resemblance to their referent, like using a mould of a loaf of bread for "bread". This category is sometimes included in the partial/associated objects category.
- Artificial symbols are abstract symbols that do not have a direct resemblance to their referent, such as having a 3D shape (i.e. an apple) that is attached to a cafe door be used as the symbol for "cafe". Beukelman and Mirenda include textured symbols in this category. An example of a textured symbol is using a piece of spandex material to denote "bathing suit".
- Three-dimensional symbols may be identical objects, parts of objects, or associated objects. A three-dimensional symbol will share similar features of the focused object, creating a meaningful symbol.
- Two-dimensional pictures, such as photographs and line drawings, are the most abstract type of tangible symbols. They are commonly used for both expressive and receptive communication, whereas the three-dimensional symbols are often used for receptive only communication (i.e. to cue the individual for upcoming events).
The type of tangible symbol used is chosen based on the cognitive and sensory abilities of the learner/user.
The meaning behind each symbol is not universal, but by using a symbol
the individual is familiar with, a meaningful symbol is created.
Tangible symbols should be constructed by meaningful and motivating
symbols that will provide the individual with the most opportunities to
practice using the new system.
Users of tangible symbols
Individuals
who can benefit from using tangible symbols include those who may lack
the skills to communicate using verbal speech or other various
communication systems such as sign language. Users of tangible symbols
may include individuals with cognitive disabilities (including developmental delay and intellectual disability), sensory and/or visual impairments (blindness and/or deafblindness), developmental disabilities (such as autism spectrum disorder), and orthopedic impairments. Rowland and Schweigert claim that tangible symbols do not require the use of high demands on the learner’s cognitive abilities, memory, visual perception, and motor abilities because they are:
- Iconic and concrete: they have a clear connection what they refer to.
- Permanent: the user does not need to recall the object, but simply be able to recognize them.
- Manipulable: can be picked up and used by the learner and who s/he is communicating with.
- Tactually discriminable: can be identified by touch.
- May be indicated through a simple motor response: such as eye gazing, touching, or pointing.
Furthermore, simple behavioral responses can be used with tangible
items. For example, learners that are unable to speak can simply point,
touch, pick up, or look (in cases of severe motoric impairment) at the
object to answer a question or make a request.
Finally, three-dimensional objects can be distinguished from one
another using touch, and therefore they are suitable for people with
visual impairments or blindness.
A study by Rowland and Schweigert found individuals who were already
able to communicate using gestures or vocalizations more readily learned
to use tangible symbols than those who did not have intentional
pre-symbolic communication skills.
Application of tangible symbols
Presentation format depends on the users visual scanning
and motoric ability. The tangible symbols can placed in front of the
user within reach, placed on a board for visual scanning, or placed in a
book for access.
Typically, tangible symbols are custom made and tailored to the
individual child. If pre-made sets are used, it is assumed that the
symbols are familiar and motivating for the user. It is important to
utilize frequently occurring and highly motivating symbols in order to
optimize opportunities for use.
Tangible symbol system offers a manual and DVD as well as an
online course. For more information on tangible symbol system
instructional strategies, please reference: http://designtolearn.com/products/tangible_symbol_systems.
Universal tangible symbol system
In
2009, Ellen Trief, Susan M. Bruce, Paul W. Cascella, and Sarah Ivy
created a Universal Tangible Symbol System. They began by developing a
survey to determine which tangible symbols were already in use, new
activities and concepts for which tangible systems are needed, and
participant preferences for tangible symbols from a pilot study.
Participants included teachers and speech-language pathologists
from four New York City schools. Following the survey, an advisory
board consisting of directors of the New York City schools,
speech-language pathologists, the designer and manufacturer of the
symbols, a representative from the Perkins School for the Blind, college
professors, and a graduate research assistant reviewed and discussed
the results. This resulted in the establishment of the 55 universal
tangible symbols seen in the chart below. However, this universal
tangible symbol system should not replace a system already established
for an individual.
| Activity | Chosen symbol |
|---|---|
| Dismissal | Strap with a buckle |
| Bathroom | White tile with a black edge |
| Gym | Tennis Ball |
| Speech | Mouth or lips |
| Classroom | Doorknob |
| Literacy | Small, thick book |
| Circle time | Wooden circle |
| Outside | Three stones |
| Music | Bells |
| Occupational therapy | Three beads |
| Physical therapy | Squishy ball |
| Snack | Small, empty snack bag |
| Cookie | Cookie |
| Computer | Floppy disc |
| Art | Paintbrush |
| Sensory | Small tube of lotion |
| Rest time | Small square of a blanket |
| Nurse's office | Large Band-Aid |
| Toothbrush | Toothbrush |
| Cooking | Measuring spoons |
| Orientation and mobility | Tip of a long cane |
| Arrival | Plastic hands |
| Math | Unifix cube |
| Science | Magnet |
| Vision | Small eyeglasses |
| Center time | Clothes pin |
| Drink | Cup |
| Lunchroom | Spoon |
| Break | Timer |
| No | Raised "X" |
| Community | Piece of a tactile map |
| Stander | Vinyl square |
| Orthodics | A half-cup measuring cup with a Velcro strip |
| Calendar | Piece of a calendar from American Printing House for the Blind |
| Walk | Shoe or sneaker |
| Light box | Plastic piece from a light-box kit |
| More | Piece of red velvet |
| Games | Spinner |
| Food | Small plate |
| Finished | Spool on a cord |
| Juice | Juice box |
| Bubbles | Bubble wand |
| Milk | Milk box |
| Yes | Raised "O" |
| "Itsy Bitsy Spider" | Plastic spider |
| "Twinkle, Twinkle" | Raised, shiny star |
| "Wheels on the Bus" | School bus |
| "Alphabet Song" | Raised letters "A," "B," and "C" |
| Bedtime | Piece of a comforter |
| Park | Metal chain |
| Church or temple | Smooth molding in the shape of a roof |
| Bath time | Small bar of soap |
| Set the table | Piece of a placemat |
| Do the dishes | Small dish |
| Car ride | Car keys or house keys |
