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FACTORS TO CONSIDER WHEN EVALUATING AND IMPLEMENTING A COMPUTER BASED AAC INTEGRATED SYSTEM WITH THE ACTIVE ADULT

Alicia Woyton Koontz, MS, ATP
HealthSouth Harmarville Rehabilitation Center
P.O. Box 11460, Guys Run Rd.
Pittsburgh, PA 15238
Voice: (412)826-2776
FAX: (412)828-1345
Internet: awoyton@city-net.com

Web Posted on: December 12, 1997


In today's world, computers are useful and powerful tools for performing various tasks in work, school, and home settings. In fact, it is uncommon to encounter a business, organization, or school who does not use computers on a daily basis. With the ongoing popularity of the Internet, it is also no surprise that businesses and households across the world are going "on-line" to acquire information and resources, send electronic messages, or just browse for entertainment purposes. Nonetheless, due to the increased use of computers in society, there is a greater demand on individuals with disabilities to gain access to computer technology as a means to accomplish communication, vocational, educational, and personal goals. Tapping into this technology, in most cases, requires a thorough assistive technology evaluation to determine the best way to access the computer. The focus of this paper is to examine the factors that help determine what is the most appropriate assistive technology device for the adult individual when the primary need is communication. In addition, complicated issues pertaining to the implementation of computer-based augmentative/alternative communication (AAC) technology will be addressed.

Conducting an assessment of an individual who is referred for AAC and/or computer access can be an involved and complex process. This is especially true, if the consumer places strong demands on what tasks the assistive device must perform in his life. For example, the adult individual may opt for a system that includes speech as the primary component but also enables for written output, access to information systems, notetaking, performing calculations, and so on. One way of determining the desired outcome of an assistive device is to conduct a needs assessment. The needs identification process will determine the individual's needs and goals and will provide a basis for the assistive technology intervention (1). Identifying the needs of the consumer is the most critical component of the service delivery process and is completed at the onset of the evaluation. The information collected during the needs identification is the cornerstone for measuring the effectiveness of the final outcome(1).

The outcome of the needs identification process will help the ATP to recognize the potential for a computer-based AAC system. The needs identification process involves determining and defining life roles, performance areas, related activities, and tasks. This process may reveal that the client needs to access a computer as a tool to: procure or maintain employment, produce formal written output, perform intricate calculations, create graphical output (i.e., drawing and plotting), gain access to information resources (i.e., CD-ROM's, Internet, BBS's), perform telecommunications, and/or achieve maximal independence in his environment (i.e., turn on/off lights and appliances). In addition, the consumer may have a goal to communicate and operate a computer system in one or more of the following settings: home, work, community, or school. Any or all of these needs could potentially be met with the implementation of a computer system. Once the AAC goals and needs are clearly understood and agreed to by all team members (e.g., client, parents, spouse, employer, care providers, and/or assistive technology practitioner (ATP)), the assistive technology evaluation can begin.

In general, capabilities of the individual to be assessed for AAC begin with cognitive, linguistic, motoric, sensory, and perceptual skills the individual brings to communication. In addition, if the person is active in the community, school or workplace it may be important to observe "a day in the life of" the individual to really understand his or her communication and computer needs. More specifically, when considering a portable computer-based AAC system several consumer issues in general should be addressed. These may include but are not limited to: overall access to the system, potential mounting/transportation of the system, previous experience with assistive technology, specific tasks the system must perform and to what extent, and the physical demands expected of the device.

Access to the AAC system may be accomplished via a control interface. A control interface, such as, a keyboard, pointing device, switch, joystick, etc. can be utilized to access a computer based AAC device. A thorough evaluation is necessary to determine the most effective and efficient means for the individual to access the system. Whether the access method is the keyboard on a notebook computer or a single switch, the control interface and all its components should be identified prior to equipment trials.

Another important factor involves potential transportation of the device. Knowing how one gets from point a to point b is important information in terms of deciding if and how the device will be mounted or carried. Does the client ambulate with the use of an assistive device? Does the consumer use a power or a manual wheelchair for primary mobility, or a combination of both? In any case, special arrangements may need to be made to transport the chosen device to as many different settings as the individual indicates.

The next issue involves the client's prior assistive technology experience. If the individual is an experienced computer user, the learning curve is shorter than it is for a new computer user. Most likely, the new computer user will need a considerable amount of training, because not only will he need to learn specific AAC software but also the computer's system software (i.e., Windows 95 or Macintosh System 7.5) and all other software and hardware components. Also with a new user, the type of computer system will need to be determined (Macintosh or IBM). The environment in which the system will be utilized, i.e., work or school, may influence this decision. Also, if an individual has a parent, spouse, or significant other who is familiar with a particular system, he may choose to go with the same system type so that the support member may provide assistance in learning the new system.

Identifying the demands on the AAC system prior to equipment trial will help to limit the number of candidate systems needing to be considered. This can be best illustrated with the following example. Conducting private phone conversations and maintaining full client confidentiality was critical for a woman with unintelligible speech who shared an office space with a co-worker. Many of the dedicated AAC devices considered only provided her with a means to conduct conversation via an external synthesizer in conjunction with a speaker phone. This was not acceptable by her employer and a computer- based system known as KeyWi by Consultants for Communication Technology was implemented on a personal notebook computer. The KeyWi system enables for speech to be delivered directly through the phone line via a phone interface. With a set of headphones, the user can conduct private conversations as well as benefit from delivering a clear and crisp synthesized voice heard at the other end.

Another factor that can influence the type of system chosen is the physical parameters that the consumer may desire in an AAC system. Examples of these parameters may include: continuous operation for x hours (where x is any number) per day, clear and precise digitized or synthesized speech, user adjustable volume control, color screen capabilities, appropriate weight and size, and/or optimal location of special keys (i.e., power and reset buttons).

After addressing the above issues, the individual should be offered the opportunity to experiment with various AAC devices and preferably those that fit the criteria established by the needs assessment and preliminary information. Trial and error with potential candidate systems may involve evaluation with both dedicated and computer-based AAC devices. Advancements in technology (infrared ports on devices) have enabled for dedicated devices to interface with computers without being physically tethered to the computer. In addition, sophisticated dedicated devices can offer the user word processing, notetaking, printing, and environmental control capabilities but may or may not be limiting depending again on the device goals of the user. Nevertheless, it is still important to consider dedicated devices as potential candidates for an AAC system.

Also during the evaluation, conducting a discussion with the consumer and support members regarding the advantages and disadvantages of a computer-based AAC system may be beneficial. There are numerous advantages to using a computer-based AAC system. For one, if the individual has good categorization skills, he or she may benefit from the use of dynamic displays to facilitate communication. Many of the more sophisticated AAC software programs feature dynamic displays. Dynamic displays makes possible a large symbol set, eliminating the need for multi-meaning symbols and allowing direct association between a symbol and the language it represents. At the same time, while the total number of symbols becomes unlimited (for all practical purposes on the most powerful dynamic display systems), the number of symbols displayed at one time can be kept to a minimum in order to reduce visual perceptual load (2).

Although choosing the most appropriate AAC system should not depend on cost, it often time does. Today's notebook computers can provide the individual with the powerful resources to drive the AAC software at a reasonable price. Most dedicated devices actually have larger price tags compared to dynamic display computerized devices which have more capability, especially in terms of storage and ability to upgrade. Furthermore, some "modern day" dedicated devices with comparable price tags have only a fraction of a percent of a notebook computer's computing capacity (2). Thus, computer-based AAC systems can provide an economical solution for individuals who do not, or have little, funding support.

In addition to cost comparison, computer-based AAC technology provides the user with a system that can be modified to adapt to life demands and expectations. Furthermore, the versatility of computer-based systems facilitates changing the language strategies and/or access methods if the user's requirements change, making a computer-based system less likely to be outgrown (2). Individuals with progressive disorders, such as multiple sclerosis and ALS may greatly benefit from this feature.

Above all, a computer-based AAC system will provide the user with the ability to operate other software programs such as a word processor, computer-aided drafting, database, spreadsheet, and/or environmental controls, which may be extremely useful based on outcome of the needs assessment.

Disadvantages of a computer-based AAC system include: the probable need to interface multiple components from multiple manufacturers, compatibility issues between software programs and access methods, and limitations on the internal batteries. The following paragraphs address these issues in terms of how they affect the implementation of the desired computer-based AAC device.

A computer-based AAC system may consist of many different components. In addition to a portable notebook computer, the hardware of a system may need to include several or all of the following: an internal/external speech synthesizer, an internal/external control interface (see previous description), a switch interface, internal/external CD-ROM drive, internal/external data/fax modems, software key (connects to one of the computer ports to provide full access of software to registered users), external scanner, external printer, external monitor, or external tape back-up system. Integrating all these components can be a very complicated procedure. While not always feasible, a good rule of thumb is to strive for a system that contains the primary components internally (within the computer). Primary components include the speech synthesizer, control interface, and those components that will be utilized most frequently by the individual. This will enable for a simpler and cleaner mounting system and minimize the number of peripherals the consumer must physically connect.

Adapted software that is required for an individual will be based on his or her AAC needs in addition to what is recommended for computer access. Most of the AAC software programs incorporate a variety of input methods. To maintain uniformity, the input method preferred to access the AAC software should also be utilized to access other computer applications as well. For instance, an individual using a trackball as the primary control interface may use it to select communication symbols in his AAC software and similarly with an on-screen keyboard software program, point and click to select characters to enter text into a word processing program.

The most challenging situation involves providing a computer-based AAC system that is accessed solely by a single, double, or multiple switch. The switch user, in general, requires the use and integration of many different hardware and software components. In terms of hardware, it is important to make sure that all the components are compatible with the type of computer system as well as with each other. An example of the later case may be that the switch jack on the switch interface is of a different diameter than that of the switch plug. As a result, an adapter may need to be provided to enable the connection to occur. In addition to ensuring hardware compatibility, the ATP must determine the best method for mounting the computer system, speech synthesizer (if external), switch interface, switch, software key, and/or other peripherals (as necessary) on a power wheelchair, manual wheelchair, scooter, or other mobility system. Commercially available systems may offer the ATP numerous mounting possibilities, however, every individual has unique needs and may require special adaptations in order to obtain the optimum configuration.

As discussed above, the input method used to access the recommended AAC software is often the same as it is for overall computer access. Frequently, one of the problems that switch users who use computer- based AAC systems face is in the ability to independently switch between an AAC program and an on- screen scanning software program which gives them access to all other software programs on the computer. Only one completely integrated software program containing both communication and computer access components, E Z Keys for Windows or Scanning WSKE for DOS by Words+, enables for a seamless swap between communication and scanning access to the computer desktop via a switch. Majer- Johnson Co., recognized this need and incorporated a feature called Ke:nx Aware into their AAC Macintosh software, Speaking Dynamically. Ke:nx Aware enables for a Ke:nx on-screen scanning keyboard (available from Don Johnston, Inc.) to appear automatically on the display when the user has exited out of Speaking Dynamically. The scanning keyboard can then be utilized to access other applications via the same switch that used to access Speaking Dynamically. Currently, many AAC software programs exist that do not enable for a seamless transition to an on-screen scanning software program via the same switch which could potentially have an impact on the user's choice system.

Power consumption is another factor to consider when recommending and implementing a computer-based AAC system. Notebook computers have sufficient battery life to operate for approximately 2-3 hours, depending on the model. This is usually not enough to enable the user to communicate for an entire work day. This limitation in battery capacity may require assistance from others in changing the battery or connecting the computer to an electrical outlet. Alternative power sources may be implemented to provide the user with the necessary power to communicate for longer hours. Some commercial products utilize the batteries of a power wheelchair to power the computer. Notebook computers (which are quite hungry in comparison to AAC devices) require approximately one percent of the wheelchair's battery capacity per hour for full operation (3). In addition, these battery adapters can provide power to other hardware components like external synthesizers, external CD-ROM drives, etc.

In conclusion, there are many steps to evaluating and implementing a computer-based AAC system with the active adult. During the initial needs assessment, device characteristics are determined based on the individual's abilities, goals and expectations. Through a comprehensive evaluation, the individual may demonstrate the potential to utilize computer-based AAC technology. Determining the most appropriate access method will predict some of the hardware and software requirements of the system. Incompatibilities in hardware and software components in addition to limited battery capability can become barriers in respect to implementation unless alternative measures are taken. Regardless of how complicated or challenging the situation may appear to be, advanced technology is currently available to provide users with the best possible AAC system that is efficient and effective in assisting them to perform the physical demands required by society, work, home or and/or school.


(1) Cook, A.M., and S.M. Hussey, Assistive Technologies: Principles and Practice, St. Louis, MS: Mosby - Year Book, Inc., 1995.

(2) Woltosz, W.S., "Dynamic Displays: the Changing Face of Augmentative Communication", Words+, Copyright (c) 1994.

(3) Snell, E. and L. Silver, "Extending the Functional Day for Powered Wheelchair Based Technologies", Proceedings of the 1994 RESNA Annual Conference June 17-22, 1994.