SECTION 5:
TYPES OF AAC DEVICES

1. CHARACTERISTICS OF AAC DEVICES

AAC devices refer to a class of durable medical equipment that serves a common purpose: the treatment of the expressive communication impairments that interfere with a person’s meaningful communication in current and projected daily activities. As is further explained in Section 3, individuals with severe dysarthria, aphasia, and apraxia who are unable to meet the communication needs that arise in the course of their daily activities through natural speech, gestures, and writing, use AAC devices to communicate. In addition, as was explained in Section 4, because AAC devices provide a viable means -- and will be the only means -- to achieve effective communication, they are a reasonable and necessary component of speech-language pathology treatment for these individuals.

An AAC device is incorporated into a treatment plan as a tool that enables an individual with a significant communication impairment to obtain, maintain, or regain communication capabilities. Such a device merges a variety of technologies that are specifically designed and configured to allow an individual to communicate independently for a variety of different reasons, across environments (home, medical settings, community, work), with familiar and unfamiliar partners, and over time. Selecting the appropriate device for an individual beneficiary requires an understanding of the technology as well as expertise in the types of speech and language impairments that interfere with functional communication. An SLP and other allied health professionals (e.g., occupational therapist, physical therapist, rehabilitation engineer) as necessary conduct an assessment process (outlined in detail in Section 3), to recommend and confirm the most appropriate AAC device to enable an individual to meet his or her daily communication needs.

1. AAC Device Categories

1. AAC Devices With Digitized Speech Output

AAC devices employ two principal means of speech production: digitized and synthesized speech. In terms of the qualitative aspects of the speech signal (pitch, resonance, and melody), digitized speech is more natural sounding than synthesized speech because it is a time sampled replication of actual human speech. Both digitized and synthesized devices produce speech that is highly intelligible (understandable) to the listener (Rupprecht, Beukelman & Vrtiska, 1995). Digitized speech output AAC devices represent a single category of AAC devices (Category #1). Digitized speech output essentially is natural speech that has been recorded, stored, and reproduced. Although digitized devices vary in physical dimensions, storage capacity and access methods, their fundamental components include a microphone, a series of filters, and a digital-to-analog converter. Thus, the reproduced speech output is a close replica of the original speech entry. The professional literature describes AAC devices with digitized speech as ‘closed’ systems because the device’s entire capacity for speech output is limited to the words, phrases, or messages that have been pre-stored for the user, ideally by someone of the same gender, under the direction of the treating SLP. Digitized speech devices also are called ‘whole message’ systems, because they can provide the user with an entire phrase, sentence, or message that can be accessed by a single selection on an AAC device. Individuals who do not have the linguistic capacity to formulate messages independently; who have cognitive or language impairments; and who are unable to generate messages through spelling and/or word-by-word message development (such as those with severe aphasia due to cortical stroke typically require a ‘whole message’ digitized AAC device.

The amount of language that can be stored in a digitized speech AAC device varies greatly. The memory capacity ranges from a minute or two an hour or more of speech. Examples of digitized speech devices are displayed in Figure 2.

Figure 2: Digitized Speech AAC Devices



 

 

 

 

Message Mate Digivox

Words+, Inc. DynaVox Systems, Inc.

 

Tables 8-11 below lists examples of digitized speech AAC devices. The tables are categorized by recording time and grouped according to the modifiers in the proposed NCD.

Table 8: Digitized Speech Output Devices -- Less than 4 minutes

Device Name Manufacturer	Recording Time (minutes)	Levels	Model #	Price (retail)
ActionVoice 2 Enabling Devices	2.0	1	ACTV	$595
BigMack AbleNet, Inc.	0.3	1	1-BM	$86
Cheap Talk 8 Enabling Devices	0.6	1	1389	$200
Fifteen Talker The Attainment Company	2.0	1	ATT-15C	$489
Five Talker The Attainment Company	2.0	1	ATT-059C	$349
Hawk II Adam Lab, Inc.	2.0	2	Hawk II	$300
Hip Talker Enabling Devices	1.0	1	5016	$165
MessageMate 20/60 Words+, Inc.	1.0	1	MM20/60	$549
MessageMate 20/120 Words+, Inc.	2.0	1	MM 20/120	$749
One Step Communicator AbleNet, Inc.	.25	1	One Step	$99
SpeakEasy AbleNet, Inc.	4.3	1	1-SE3	$399
Step-by-Step Communicator AbleNet, Inc.	1.25	3	Step-by-Step	$149
Step Talk Switch Plate Enabling Devices	1.25	1	1355	$79
Talk Back 24 Crestwood Company	4.0	1	3034	$599
Tech/Speak 2 x 32 Advanced Mulitmedia Devices, Inc.	2.1	2	X071232	$445
Tech/TALK 6 x 8 Advanced Mulitmedia Devices, Inc.	3.2	6	X07068	$395
Ultimate 4 Tash, Inc.	.25	1	2800	$99
VoicePal Adaptivations	1.0	1	VP-B	$325
VoicePal Max Adaptivations	1.0	1	VP-MAX-T60	$555
VoicePal Pro Adaptivations	1.5	1	VP-PRO-T90	$570

 

Table 9: Digitized Speech Output Devices -- 4 to 8 minutes

Device Name Manufacturer	Recording Time (minutes)	Levels	Model #	Price (retail)
6 Level Communicator Enabling Devices	4.0	6	2392	$245
Black Hawk Adam Lab, Inc.	4.0	4	Black Hawk	$475
Hand Held Voice Mayer Johnson Co.	6.0	Dynamic Display	H029A	$1495
MessageMate 40/300 Words+, Inc.	5.0	4	MM40/300	$1099
SpeakEasy AbleNet, Inc.	4.3	1	1-SE3	$399
Talk Back 24 Crestwood Company	4.0	1	3034	$599
Tech/Speak 4 x 32 Advanced Mulitmedia Devices, Inc.	4.1	4	X071432	$545
Tech/Speak 6 x 32 Advanced Mulitmedia Devices, Inc.	6.4	6	X071632	$645
Tech/TALK 8 x 8 Advanced Mulitmedia Devices, Inc.	4.25	8	X07088	$445
Tech/TALK 12 x 8 Advanced Mulitmedia Devices, Inc.	6.4	12	X070128	$645

 

Table 10: Digitized Speech Output Devices -- 9 to 16 minutes

Device Name / Manufacturer:	Recording Time (minutes)	Levels	Model #	Price (retail)
Digivox2 DynaVox Systems, Inc.	16.0	48	Digivox2-16	$1600
EasyTalk The Great Talking Box Co.	16.0	4	EasyTalk-16	$1100
Hand Held Voice Mayer Johnson Co.	10.0	Dynamic Display	H029B	$1645
Macaw3 Zygo Industries	9.0	32	Macaw3	$2495
MessageMate 40/600 Words+, Inc.	10.0	4	MM40/600	$1299
SideKick Prentke Romich Company	11.5	1	SK	$1295

 

Table 11: Digitized Speech Output Devices -- 17 + minutes

Device Name / Manufacturer:	Recording Time (minutes)	Levels	Model #	Price (retail)
AlphaTalker Prentke Romich Company	37	4	AT-1	$2645
Digivox DynaVox Systems, Inc.	142	48	Digivox2-142	$3250
Dynamo DynaVox Systems, Inc.	30	Dynamic Display	DMO	$1795
Macaw 3+ Zygo Industries	19	32	Macaw3+	$2645

Because digitized speech AAC devices have a fixed amount of recording time, the number of messages and the length of messages sometimes become competing factors. While some devices have pre-assigned maximum message lengths, most devices allow for a range of individual messages of varying lengths within the total recording time available. Some also offer limited language storage and retrieval features, such as iconic encoding and levels. These are described in subsection B. Although all AAC devices with digitized speech produce a finite number of pre-recorded messages (or message units), these messages can be changed to accommodate an individual’s varying communication needs by simply recording new messages to replace those no longer needed.

2. Synthesized Speech AAC Devices

Synthesized speech output AAC devices incorporate two categories of AAC devices (Category #2 and Category #3). Synthesized speech AAC devices use a technology that translates the user’s input into machine-generated speech using algorithms representing linguistic rules, including rules for pronunciation, pronunciation exceptions, voice inflections, and accents of the language. The user is not restricted to messages that are pre-stored by someone else, as occurs with digitized speech AAC devices; rather the user creates a message using letters, words, or symbols. The AAC device then ‘translates’ the input into speech. Research examining the intelligibility of the synthesized speech output in AAC devices has found that modern speech synthesizers, such as DECTalkä designed by the Digital Equipment Corporation, which is recognized as the industry standard, have word and sentence intelligibility of over 95% when compared to natural speech and are preferred over impaired speech by both unfamiliar and familar communication partners. (Rupprecht, Beukelman & Vrtiska, 1995).

Synthesized speech AAC devices are ‘open’ systems because users independently can construct original messages. This is often referred to as generative speech capability. Individuals who need devices with synthesized speech possess the cognitive and linguistic capacity to formulate messages independently. These individuals typically have primary physical impairments with dysarthria or apraxia secondary to ALS, cerebral palsy, multiple sclerosis, Parkinson’s disease, brain stem stroke, and those persons with traumatic brain injury who have relatively preserved linguistic and cognitive skills. In addition, individuals with mild language difficulties, including some with mild aphasia, can utilize synthesized speech devices to generate words and sentences independently or to use pictographic symbols to generate language.

As further described below and in Section 3, synthesized speech AAC devices are distinguished by two unique features: (1) the method by which the user generates messages and (2) the method by which the user accesses the device. When considering a synthesized speech AAC device, the treatment goal is to identify the device that allows the individual with a severe communication impairment to communicate as efficiently as possible across environments. Therefore, the assessment process must match a user’s linguistic skills to the message formulation, storage, and retrieval features available in a particular AAC device. The assessment process also must identify the most appropriate user interface, i.e., a way to access the device to produce messages.

1. Category #2: AAC Devices With Synthesized Speech Output, Which Require Message Formulation By Spelling And Device Access By Physical Contact Direct Selection Techniques

Category #2 devices require spelling (which includes using a limited number of alphanumeric codes) for message formulation and access by physical contact direct selection techniques. Clinical indicators for this category require that the individual have sufficient spelling skills to generate messages independently and be able to access the device using a physical contact direct selection technique (pointing with finger, head stick, mouth stick, etc.). Finally, based on the communicative needs assessment, persons requiring Category #2 devices do not need to construct, store, and retrieve lengthy messages. Defining features of this category of AAC devices are described below.

1. Message Generation: Spelling

The most straightforward way to formulate a message is for the non-speaking individual to spell letter-by-letter using an AAC device with an alphanumeric keyboard. An important clinical indicator is that the person be able to spell sufficiently well to generate messages. Synthesized speech devices in this category are technologically unique in the method of message generation, i.e., spelling. Examples include the Link and the LightWriter [model # 25/35] as illustrated in Figure 3.

Figure 3: AAC Devices With Synthesized Speech Output, Which Require Message Formulation By Spelling And Device Access By Physical Contact Direct Selection Techniques





Link Light Writer SL 25/35

Depending on the ability of the user, the process of generating messages using spelling can be laborious. For this reason, some spelling-based AAC devices offer a limited selection of rate enhancement strategies such as alphanumeric encoding. This feature is discussed in section II.

2. Access method: Direct selection

Operating an AAC device by direct selection requires that an individual make physical contact with the selection set (letters, symbols, codes) of the device to construct a message. The individual can make physical contact using a body part (e.g., fingers, toe) or by using an adaptive peripheral device (e.g., a splint, mouth stick, head pointer, head mouse). The standard computer keyboard is an example of a device that uses direct selection (by the fingers) as an operating technique. The keyboard, display, or touch screen of AAC devices are similar to computer keyboards but typically are more adaptable. To accommodate persons with a range of physical and/or visual impairments many AAC devices permit the ‘keys’ or ‘cells’ to be configured in different sizes; permit variable amounts of pressure or time required to activate keys or cells; and enable key repeat features to be turned off.

AAC devices in all other categories allow for multiple access methods, i.e., both direct and indirect selection methods. Only this category of AAC devices limits the operating method to physical contact direct selection. Examples of AAC devices are listed below in Table 12.

Table 12: AAC Devices With Synthesized Speech Output, Which Require Message Formulation By Spelling And Device Access By Physical Contact Direct Selection Techniques

Device Name (Model #)	Rate Enhancement/ Message Storage (Yes/Minimal/No)	Direct Selection Options (Keyboard/Touch)	PRICE (retail)
LINK	Y	Keyboard	$1,395
LightWriter SL25LQBDO SL25LQFDO SL25LQF/BDO	Y	Keyboard	$3,095 $3,345 $3,595
LightWriter SL35LQBDO SL35LQFDO SL35LQF/BDO	Y	Keyboard	$4,070 $4,425 $4,780
LightWriter SL35C SL35 Big Keys	Y	Keyboard	$5,585 $5,795

1. Category #3: AAC Devices With Synthesized Speech Output, Which Permit Multiple Methods Of Message Formulation And Multiple Methods Of Device Access.

The devices in this category provide expanded options for constructing, storing, and retrieving messages, and they offer multiple methods for accessing an AAC device. An important clinical indicator for this category is that an individual be able to generate language independently and efficiently using text, words, and/or pictographic symbols. Other indicators include the individual’s need for extensive strategies for message construction, message storage, and message retrieval, and the need for individual’s indirect methods of access. The message generation and access features in this category are discussed in more detail below.

1. Message generation: Multiple methods

This category of AAC devices represents language using text and/or pictographs. Thus, a non-literate user with the cognitive and linguistic abilities to generate messages independently can use familiar pictures or icons (or ones they can learn) to communicate their thoughts, opinions, and needs. For example, an individual may store the message ‘Please call my wife’ and select it later by pointing first to the cell with the printed word ‘phone,’ and then to the cell with a picture of his spouse. Synthesized speech AAC devices with multiple message generation methods also enable users to store many messages and retrieve them efficiently using a variety of rate enhancement techniques. Figure 4 below illustrates two AAC devices in this category, the Freestyle and DynaVox, both of which offer touch screens which the user can operate by pressing an item or box on the screen to construct a message.


Figure 4:AAC Devices With Synthesized Speech Output, Which Permit Multiple Methods Of Message Formulation And Multiple Methods Of Device Access



Freestyle DynaVox 3100

Assistive Technology, Inc DynaVox Systems, Inc.

During the AAC assessment process, the SLP determines whether the individual possesses the linguistic capacity to formulate messages independently. If so, the SLP seeks to establish whether the person needs a device that can store a large number of messages, and can store lengthy messages and retrieve them efficiently. In such cases, the individual must be able to rely primarily on icons or pictographs to produce their messages as well as spelling to generate specific words or messages for which there are no appropriate icons or pictographs. This category of AAC devices is unique and often is required by individuals with primary physical impairments (dysarthria), as well as by some individuals with moderate aphasia and apraxia. The devices in this category are identified in Table 13.

Table 13: AAC Devices With Synthesized Speech Output, Which Permit Multiple Methods Of Message Formulation And Multiple Methods Of Device Access

Device Name Manufacturer	Screen Type	Model #	Price (Retail)
Axis 1600/Vanguard Prentke Romich Company	Dynamic	AXS-VGW	$6,995
Axis 1600/Scan/WiVox Prentke Romich Company	Dynamic	AXS-WSV	$5,995
Dynamyte 3100 DynaVox Systems, Inc.	Dynamic	DMYT3100	$5,995
Dynavox 3100 DynaVox Systems, Inc.	Dynamic	DNV3100	$6,495
Freedom 2000 Words+, Inc.	Dynamic	Freedom 2000	$5,995
Freestyle Assistive Technology, Inc.	Dynamic	FS 32/1.1	$6,615
Liberator Prentke Romich Company	Static	LIB2KEY	$8,945
Optimist 100 Zygo Industries	Dynamic	Optimist 100	$4,995
Optimist 160 Zygo Industries	Dynamic	Optimist 160	$5,995
Pegasus Lite Words+, Inc.	Dynamic	Pegasus Lite	$6,995
Synergy mAAC 2 Synergy	Dynamic	Synergy mAAC 2	$8,675
Vanguard Prentke Romich Company	Dynamic	VG-NON	$7,995

1. Access (user interface): Multiple methods

1. KEY AAC DEVICE CHARACTERISTICS
1. Methods Of Displaying Language

Currently, AAC devices use two distinct methods of displaying language/message components (letters, words, icons, pictures): dynamic displays and static displays.

1. Dynamic Displays

A dynamic display depicts language in an electronic format. As a result, the information displayed is ‘changeable’ by the user. That is, when the user selects a location on the display, the device either speaks a message immediately or changes what appears on the screen. Figure 5 illustrates an AAC device with dynamic display and AAC software. In addition to displaying language, dynamic displays are designed to facilitate the effective and efficient retrieval of language. Messages typically are organized by topic into ‘electronic pages,’ which become familiar to the user. These may include, among others, context-based pages (home, physician’s office), taxonomic-based pages (family, foods, medicines), conversational pages (greetings, partings), and alphanumeric pages (alphabet). Individuals learn to compose messages by navigating through the pages electronically. This dynamic display allows the user to see only the message components that are most relevant at the time and to switch easily between display screens. Some devices with dynamic displays have onscreen keyboards so that literate users can spell words when necessary.

Figure 5: AAC devices with dynamic displays

Dynamo DynaMyte 3100

DynaVox Systems, Inc DynaVox Systems, Inc

(digitized speech output) (synthesized speech output)

Dynamic display AAC devices are available for users who require ‘open’ systems (devices that use synthesized speech) as well as for users who require a ‘closed’ system (devices that use digitized speech). Dynamic display devices are clinically indicated for individuals who need to access multiple levels of vocabulary independently to generate messages. Dynamic displays also are appropriate for individuals who have difficulty learning and remembering a large number of codes. Because dynamic displays essentially are computer screens, devices with dynamic displays typically offer a range of rate enhancement features and message storage options. They are available among devices in Categories # 1 and # 3 and the AAC software accessories category.

2. Static Displays

A static display provides language symbols in a tangible format. An example of a static display is a computer keyboard, which has a fixed layout of letters, numbers, punctuation marks and operational command keys. Most digitized speech AAC devices have static displays, which typically are constructed by an SLP. Figure 6 illustrates a digitized speech device with a static display.

Figure 6: AAC Digitized Devices With Static Displays

 

This Minspeak device enables a user to access a large vocabulary using iconic sequences

The user selects a picture and the device speaks the stored message.

Liberator MessageMate

Prentke Romich Words+, Inc.

(Synthesized Speech) (Digitized Speech)

Static displays often are used for individuals who have limited vocabulary needs, especially those able either to change displays independently or to have others who are readily available do so. At the same time, displays that are ‘static’ do not necessarily generate a limited amount of language. For example, a static display containing the letters of the alphabet can produce any message. Likewise, by using encoding techniques, a large number of messages. Devices that use a Minspeak approach are good examples of static display devices that generate many messages.

2. Methods of Storing and Retrieving Language

The goal of all AAC devices is to allow individuals to meet the communication needs arising in the course of their daily activities. Therefore, a major design consideration in AAC devices is the need to provide access to more language/messages than can fit within the physical dimensions of a given display. This characteristic is called ‘language storage and retrieval.’ AAC devices use two methods to store/retrieve language: levels and message encoding techniques. These features can be found in AAC devices in Categories #1 and #3, and to a lesser degree, among the AAC devices in Category #2.

1. Levels

Many devices (both digitized and synthesized) use a ‘level’ approach to language storage and retrieval. ‘Level’ capability means that each cell shown on the display can produce more than one message. Multiple levels permit the storage of more symbols, letters, words, or other messages than can fit within the physical dimensions of an AAC device display. By offering a ‘level’ alternative, AAC device users have access to more of the language they require to meet their communication needs.

A user with many levels who needs access to a large vocabulary must recall where a desired message is located or stored. Because this may be very difficult for the individual, AAC devices offer different strategies to aid users in retrieving messages efficiently. Dynamic display devices allow vocabulary to be organized in ways meaningful to the user and take advantage of an individual’s ‘recognition memory.’ Devices with static display devices that use a level strategy require multiple overlays. Of course, persons who are physically unable to change the overlay by themselves because of upper extremity involvement will be dependent upon others to do so.

2. Message Encoding

Some devices offer the use of numeric, letter or iconic codes as a way to store and retrieve messages, and as described below, as a rate enhancement technique. ‘Coding’ capability means that users, by selecting the cells of a display in sequence, can generate a large number of stored messages from just a few ‘hits.’ Some form of coding is available across all AAC device categories. An important clinical indicator for language encoding is the user’s ability to learn (and recall) the codes. Types of coding used in AAC devices include the sequencing of numbers, letters (abbreviation expansion, instant messages), words/icons (semantic encoding/Minspeak) and Morse code (dits and dahs). Clinical indicators for encoding are determined through the AAC assessment process and relate to the type and number of codes to be memorized. An advantage of coding is that with just a few selections, individuals can access longer messages and enhance their rates of communication. A disadvantage is that individuals must memorize codes to use them effectively.

1. Encoding Strategies

1. Methods for Enhancing Rate

While AAC devices provide a way to communicate for people unable to speak, they generate language at a far slower rate than natural speech. Most individuals who use an AAC device want to approximate normal conversational rates but are limited by the technology and such factors as deficits in cognitive/linguistic, motor, and/or sensory skills. Rate enhancement techniques maximize output (produce a sufficient quantity and quality of messages efficiently) while minimizing input (fewer keystrokes or activations). In other words, with rate enhancement options, users can produce more language with fewer keystrokes. Some are available across device categories. The two primary rate enhancement strategies are encoding and prediction. Encoding strategies are discussed above. A description of prediction strategies follows.

1. Message Prediction

Message prediction techniques speed the message generation process by offering predictions to complete words or phrases based on prior user input. This contrasts with encoding strategies, which require the user to memorize and recall multiple code sequences to construct their utterances. The algorithms employed to guide predictions in AAC devices are based on research examining frequency of usage in the target language (English). For example, in a device that has single-word prediction such the LightWriter by Zygo, after the user types ‘th’ the device predicts ‘the’ because it is the most frequently used word in the English language beginning with the letters ‘th.’ Individuals who have sufficient spelling and reading skills to spell the beginning of words and to recognize the desired word from the prediction set often find prediction strategies useful in decreasing message construction time. Another clinical indicator for use of prediction strategies is lack of desire or inability to memorize alphanumeric and/or iconic codes. Because the user simply selects the desired word from the prediction set, no memorization is required. Extensive message prediction-based strategies are available only on synthesized speech based devices in Category #3 and in the AAC software accessory category. AAC devices in Category #2 may offer limited message prediction capability.

2. Letter/Word Prediction

1. Accessories (Device Customization Components)

People who use AAC techniques and are unable to speak or write through traditional means may need different device components to enable them to use an AAC device to meet daily communicative needs. Device customization components (also referred to as AAC accessories) are technologies that permit custom adaptation of AAC devices and include a variety of switches and pointing devices, mounting systems, carrying cases, power accessories and software.

1. Switches/Keyboard Adaptation and Selection (Pointing) Devices

AAC device accessories that enable people to access AAC devices can be both electronic and nonelectronic. Some are designed to support direct selection; others support indirect access techniques. Table 14 provides examples of AAC Access technologies.

Table 14: Examples of AAC Access Technologies

Nonelectronic All Device Sub Categories	Electronic (Direct) Device Categories 1 & 3	Electronic (Indirect) Device Categories 1 & 3
Hand-held stylus	Light pointers	Pneumatic switch
Pointers (head, foot)	Infrared pointers	Rocking lever switch
Splints	Eye-gaze systems	Tread switch
Keyguards	Joysticks
Mouth stick	Optical head pointers
	Head controlled mice

The selection of switches, keyboard adaptations, and pointing devices is determined by the SLP and, as necessary, an occupational therapist, based on the user’s physical capabilities, such as motor skills and visual abilities, and the type of AAC device the individual needs for communication.

3. Mounting Systems

Mounting systems are necessary to place AAC devices, switches and other access peripherals in a stable position relative to the user. Without appropriate mounting for a device and/or switch, individuals with severe motor impairment are unable to use appropriate AAC devices to transmit messages. Good positioning underlies successful access and device use. Depending upon an individual’s disabilities and communication needs, mounting systems may be required on a wheelchair, desk, bed or lap tray, or other locations where the individual resides throughout the day.

4. Carrying Cases

Carrying cases are needed for individuals who are ambulatory and need to communicate in a variety of locations. Specially designed carrying cases are available for some devices. Carrying cases also are used to protect a device. For example, nonambulatory individuals who use their devices in multiple contexts need to safely transport the device from one location to another on a regular basis. Carrying cases are designed to accommodate a user’s fine motor skills to enable a person with physical disabilities to open and close the case and communicate effectively.

5. Power

Electronic communication devices require a source of power. Individuals cannot be tethered to a wall outlet in order to communicate. AAC devices therefore require batteries, battery chargers, auto adapters, and AC adapters. While batteries and AC adapters always are included with an AAC device, individuals who use their devices most of the day often need to purchase several batteries and chargers to insure they can communicate regularly.

6. AAC Software

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