Intervention refers to a balanced process in which rehabilitative procedures designed to improve deficient skills are implemented in concert with management strategies designed to minimize a deficit's adverse effects. This process is maximized when remediation and management are implemented in a timely fashion, specific to the client's needs, and generalized across settings (ASHA, 2005). For many speech-language-hearing professionals, intervention for (central) auditory processing disorders [(C)APDs] remains a challenge due to the complex nature and impact of these disorders.
Poor (central) auditory processing may manifest behaviorally in a variety of ways, including deficient academic performance, impaired communication, and altered sense of self. This diversity in scope and severity implies not only that the assessment and intervention processes will involve a team of professionals, each contributing uniquely to the overall understanding of the (C)APD, but also that the elements of the intervention process itself will likely vary from simple to extensive. Although (C)APD may be a complex problem, intervention need not be complicated.
Many professional resources are available that describe specific therapies and strategies for developing individualized intervention programs for listeners with (C)APD. These resources have three basic elements in common—activities, identification of barriers, and need for collaboration—or the ABCs of intervention for (C)APD.
A is for Activities
Remediation for (C)APD involves specific activities to improve specific auditory and related skills. Bottom-up training programs are designed to improve auditory skills, including auditory discrimination, dichotic listening, and temporal processing (Ferre, 2002). Top-down therapy programs focus on improving metalinguistic and metacognitive skills, important for minimizing the impact of the (C)APD on functional communication (Ferre, 2006). These formal therapies are appropriate and important components of a (C)APD intervention plan and are discussed in detail in the literature (Chermak & Musiek, 2006).
In addition to formal therapy, professionals should encourage parents, teachers, and students to "play" with sounds and language using games that require auditory discrimination, dichotic listening, localization, temporal processing, and related top-down skills. These simple games, similar in scope to these training paradigms, can be implemented daily, at little or no cost, at home, in the car, or at school, and they meet the goal of extending rehabilitation beyond therapy to maximize mastery and generalization of skills for listeners with specific (C)APD.
To practice auditory discrimination—the ability to discriminate, identify, and recognize fine and/or rapidly changing acoustic cues—consider simple rhyming games such as "give three rhymes for cat;" creating ending-sound word chains in which each player says a word that starts with the last sound of the previous word (e.g., hiT – ToP – PaTH – THeN – NaMe…); or the "telephone game," in which a message is whispered down a line of players or around a circle.
Dichotic listening training can improve binaural integration and separation skills, which require that the two cerebral hemispheres work together (Weihing & Musiek, 2007). In dichotic listening training, the listener hears two (or more) different targets presented simultaneously, one or more to each ear, and is asked to attend to one (separation) or both (integration) signals. Informal binaural separation/integration training can be accomplished by asking the student to repeat one or both targets spoken by individuals standing on either side of the listener. While not a true dichotic experience, the activity approximates the skill. As with formal dichotic training programs, relative loudness levels between the two speakers can be varied, as can language of the target, for example, by asking the listener to repeat numbers given by two speakers versus repeating sentences or answering questions.
Localization, or the ability to locate an acoustic target in space, can be practiced through games such as "Blind Man's Bluff" and "Marco Polo." For very young children, "find the sound" involves having the child stand with eyes closed while a parent or sibling shakes a set of keys (or other noisemaker) at various locations near the child's head (e.g., above, below and to the left, etc.) and asking the child to try to take the keys or point to the sound source.
Temporal processing, the ability to use timing aspects of the signal, includes temporal patterning, or the ability to recognize and use acoustic patterns such as those that occur in running speech. Games such as "MadGab," "Bopit," "Bopit Extreme," "Simon," and "Simon2" facilitate pattern recognition practice at home or school.
Enhancement of auditory-related skills may include games to enhance auditory vigilance (waiting for the target to change), interhemispheric communication, and/or the ability to use visual, linguistic, and cognitive cues. Vigilance-enhancing games include "Simon Says," "Twister," "duck-duck-goose," "musical chairs," and "cake walks." Communication across the corpus callosum should be enhanced by any activity that requires interhemispheric communication, such as gymnastics, karate, playing an instrument, dancing, tossing a ball from one hand to another, "Simon," "name that tune," or "feely bag" (players reach into a bag and identify an object without looking at it).
In addition, the latest generation of interactive video games (e.g., "Donkey Kong Jungle Beat," "Mario Mix Dance Revolution," "Eye-Toy" for PlayStation2) require whole-body integration for success.
The ability to use visual, linguistic, and/or cognitive cues is promoted through no-cost or low-cost games such as "Charades," "Read My Lips," and "Pictionary" that promote attention to and use of visual cues, or "HangMan," "Twenty Questions," crossword puzzles, "Password," "Taboo," "Catch-Phrase," and "Tribond," which stress metalinguistic and metacognitive skills.
B is for Barriers
In addition to improving skills, a goal of any intervention program is to minimize the adverse effect of the disorder on the individual. Communication is enhanced for individuals with (C)APD—and all listeners—by identifying and minimizing barriers to auditory processing. These barriers may exist in the listening environment or in the message itself.
It has been estimated that nearly two-thirds of a student's day consists of listening to and participating in spoken communication (ANSI, 2002). Thus, it is essential that listening environments be free of acoustic (e.g., noise, reverberation, distance) and nonacoustic (e.g., lighting, visual cues, or distractions) barriers. Background noise is any auditory disturbance that interferes with listening. The combination of noise and reverberation, or echo, adversely affects the ability to process what we hear by masking the acoustic and linguistic cues in the message and/or by distracting the listener from the communication event (Crandall & Smaldino, 2002). Improving classroom acoustics can involve extensive and often expensive infrastructure changes such as eliminating open classrooms, relocating teaching spaces, or altering heating or air conditioning systems.
Simpler and less expensive solutions in school and at home include closing doors and windows; carpeting rooms; using curtains, drapes, and/or acoustic ceiling tiles; placing baffles within the listening space; damping acoustically reflective surfaces; reducing radio, stereo, and television volume; changing lighting; and minimizing the number of speakers talking at once. Distance between the speaker and listener can affect speech recognition. For most listeners, a distance of three to six feet from the sound source is considered optimal (Boothroyd, 2004). By locating the listener with (C)APD nearer the primary sound source at home or in school, listening and processing are enhanced.
Nonacoustic factors such as lighting, availability of visual cues, and presence of visual and physical distractions also should be considered. Room lighting can affect ability to use visual cues and maintain attention on task. Speakers should avoid being backlit, or standing with the light coming from behind rather than on the speaker's face. Using incandescent lighting rather than fluorescent lighting eliminates the hum often produced by these lights and reduces harshness and glare, thus minimizing a source of noise and improving access to visual cues. Preferential seating, use of study carrels at home and school, and/or changes to desk or chair design can minimize visual and physical barriers that may interfere with listening or studying.
For the listener with (C)APD, what we say and how we say it can be critically important. Modifying the message by using clear speech and clear language, increasing message familiarity, and adding visual cues enhances processing for all listeners, not just those with (C)APD. Clear speech and clear language focus on enhancing speech recognition by modifying the speech or language of the talker. Too often, speakers talk too fast or too softly, drop word endings, and blur acoustic boundaries between targets (Schum, 1997). By speaking at a slightly reduced rate and slightly increased volume, spectral boundaries and characteristics are enhanced and signal timing and prosody improve, improving speech intelligibility.
While clear speech improves signal perception, clear language improves comprehension. Speakers can enhance message salience by rephrasing, minimizing the use of ambiguous and generic language, adding "tag" words (such as first, last, before, after), providing verbal cues and prompts, and verbally stressing key words. Limiting the overall amount of information presented at once, breaking long messages down into shorter sequences, and allowing "thinking" or "waiting" time before a response is required can improve message comprehension as well as the listener's ability to demonstrate understanding.
In general, the more familiar one is with the target, the easier the processing becomes. In the classroom, pre-teaching or previewing material enhances familiarity with the target and the task. Audio books, copies of teachers' notes/texts, study guides, movies, and reading aloud to children can enhance their familiarity with the subject, task demands, main ideas, key elements, and vocabulary. At home and school, prior knowledge of the rules, structure, and task demands can minimize overload. Listeners will become more familiar with and better able to use the rules of language through a combination of repeated exposure and, as needed, explicit instruction, across a variety of contexts and settings throughout the day (Ferre, 2006).
Adding visual cues to a message intensifies processing through increased neural interaction. Thus, looking and listening should be modeled by parents and teachers if the same behavior is expected from children. However, some listeners are deficient in their ability to integrate auditory and visual information and the addition of visual cues may create further confusion. In these cases, "look and listen" should be changed to "look or listen" (Bellis, 2003). The addition of complementary visual cues or use of manipulatives, examples, and demonstration (e.g., show me) improves understanding, particularly for unfamiliar or abstract information. For some students, these additional cues can be provided with simultaneous auditory input. For others, multisensory cues should be given sequentially, e.g., "look then listen," in order to minimize potential overload on integration and/or organization skills (Bellis, 2003).
C is for Collaboration
The professional scopes of practice of both speech-language pathologists and audiologists make it clear that effective assessment and intervention of (C)APD requires collaboration. Audiologists use well-controlled diagnostic tools to evaluate the integrity of the auditory system and offer deficit-specific recommendations for treatment and management. SLPs provide information concerning the cognitive-communicative aspects that relate to (C)APD, implement treatment recommendations, and communicate with teachers and related professionals regarding educational accommodations and strategies.
In addition, because (C)APD shares behavioral characteristics with other sensory processing, neurocognitive, and educational difficulties, related professionals such as occupational therapists, physical therapists, psychologists, and specialists in learning disabilities are among the team members working together to develop effective individualized intervention programs. Finally, clients and their families should be included in the process to maximize carryover of new skills and minimize the adverse effects of the disorder on daily life. Collaboration may include co-written lesson plans, joint treatment sessions, classroom visitation, or specific activities to be completed at home.
The behavioral similarity of (C)APD to other disorders suggests that treatment options and management strategies may be shared among individuals diagnosed with different deficits. For example, activities suggested by the occupational therapist to enhance a student's sensory processing skills also may be useful for the student with impaired interhemispheric integration. The classroom management strategies recommended for the student with a nonverbal learning disability also may meet the needs of the student with temporal processing deficits.
Audiologists and SLPs are uniquely positioned to share information, strategies, and resources with clients, related professionals, teachers, and parents to find creative and effective ways to meet intervention goals across a variety of settings. By looking at the whole listener and thinking "outside the box," team members may find unique approaches to seemingly different and complex problems. It's as simple as A-B-C.