You are in: eMedicine Specialties > Physical Medicine and Rehabilitation > REHABILITATION PROTOCOLS Communication DisordersArticle Last Updated: Apr 23, 2008AUTHOR AND EDITOR INFORMATIONSection 1 of 8
  Author: Renee S Melfi, MD, Consulting Staff, Orthopaedic Associates of Central New York Renee S Melfi is a member of the following medical societies: American Academy of Physical Medicine and Rehabilitation, American Association of Neuromuscular and Electrodiagnostic Medicine, and Association of Academic Physiatrists Coauthor(s): Susan J Garrison, MD, Medical Director of the Rehabilitation Center, Associate Professor, Department of Physical Medicine and Rehabilitation, Methodist Hospital, Baylor College of Medicine Editors: Everett C Hills, MD, MS, Medical Director, Penn State Hershey Rehabilitation Hospital, Assistant Professor of Orthopaedics and Rehabilitation, Assistant Professor of Neurology, Penn State Milton S. Hershey Medical Center and Penn State University College of Medicine; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; Richard Salcido, MD, Chairman, Erdman Professor of Rehabilitation, Department of Physical Medicine and Rehabilitation, University of Pennsylvania School of Medicine; Kelly L Allen, MD, Consulting Staff, Department of Physical Medicine and Rehabilitation, Lourdes Regional Rehabilitation Center, Our Lady of Lourdes Medical Center; Rene Cailliet, MD, Professor-Chairman Emeritus, Department of Rehabilitation Medicine, University of Southern California School of Medicine; Former Director, Department of Rehabilitation Medicine, Santa Monica Hospital Medical Center Author and Editor Disclosure Synonyms and related keywords: communication disorders, voice disorders, dysphonia, motor speech disorders, language disorders, aphasia, selected cognitive-communication disorders, hearing impairment THE NORMAL COMMUNICATION PROCESSSection 2 of 8
  Communication is a multidimensional dynamic process that allows human beings to interact with their environment. Through communication, people are able to express thoughts, needs, and emotions. Communication is an intricate process that involves cerebration, cognition, hearing, speech production, and motor coordination. Evaluation of a communication disorder includes consideration of all aspects of the normal communication process. Language is the transformation of thoughts into meaningful symbols communicated by speech, writing, or gestures. Thoughts are organized by the brain, specifically the left hemisphere, and encoded into a sequence according to learned grammatical and linguistic rules. These rules govern the way sounds are organized (phonology), the meaning of words (semantics), how words are formed (morphology), how words are combined into phrases (syntax), and the use of language in context (pragmatics). Speech involves the coordinated motor activity of muscles involved in respiration, phonation, resonance, and articulation. The entire system is modulated by central and peripheral innervation, including cranial nerves V, X, XI, and XII, as well as the phrenic and intercostal nerves. Respiratory muscles, specifically the muscles associated with expiration, must generate enough air pressure to provide adequate breath support to make speech audible. The diaphragm is the main muscle of expiration; however, the abdominal and intercostal muscles help to control the force and length of exhalation for speech. Phonatory muscles of the larynx generate vibratory energy during vocal cord approximation to produce sound.1 Vocal pitch and intensity are modified by subglottic air pressure, tension of the vocal cords, and position of the larynx. Articulatory muscles within the pharynx, mouth, and nose form the tone of the sound. The coordinated action of these muscles produces speech. By altering the shape of the vocal tract, we are capable of producing a tremendous range of sounds. Sound waves are transformed by the auditory system into neural input for the speaker and the listener. The outer ear detects sound pressure waves in the air and converts them into mechanical vibrations in the middle and inner ear. The cochlea then transforms these mechanical vibrations into vibrations in fluid, which act on the nerve endings of the eighth cranial nerve. Thus, the process of communication begins and ends in the brain. Various disorders may impair a person's ability to communicate. These disorders may involve voice, speech, language, hearing, and/or cognition.2, 3 Recognizing and addressing communication disorders is important; failure to do so may result in isolation, depression, and loss of independence.4, 5 VOICE DISORDERS (DYSPHONIA)Section 3 of 8
Voice is the audible sound produced by passage of air through the larynx. Voice typically is defined by the elements of pitch (frequency), loudness (intensity), and quality (complexity). By varying the pitch, loudness, rate, and rhythm of voice (prosody), the speaker can convey additional meaning and emotion to words. A voice disorder exists when the quality, pitch, or volume differs from that of other persons of similar age, culture, and geographic location. Dysphonia is classified as either an organic or a functional disorder of the larynx.6, 7 Organic disorders cause an interruption in the smooth approximation of the vocal folds.1 Such disorders include the following:
Functional disorders affect the quality and volume of the voice. They include the following:
Rule out a treatable medical condition in all patients with voice disorders. For example, a voice disorder may be one of the first symptoms of laryngeal cancer. Patients should be referred to an otolaryngologist (ear, nose, and throat [ENT] specialist) for specialized examinations, which may include peripheral oral/nasal examination, voice analysis, and indirect or fiberoptic laryngoscopy. Once an organic disorder has been either treated or excluded, the patient may be referred to a speech-language pathologist (SLP). The SLP helps the patient to produce the most functional voice possible.9, 10 Laryngectomy rehabilitation Laryngectomy remains a common procedure for the treatment of laryngeal cancer. Total laryngectomy results in the complete loss of voice (aphonia). Speaking options for the patient following laryngectomy patient include the following:
See also the following related eMedicine topics: MOTOR SPEECH DISORDERSSection 4 of 8
The production of speech depends on motor coordination of the structures of the respiratory system, larynx, pharynx, and oral cavity. Disorders of motor speech are classified into dysarthrias and apraxias.
Dysarthria refers to a group of motor speech disorders caused by a disturbance in the neuromuscular control of speech.4 It results from central or peripheral nervous system damage and is manifested as weakness, slowness, or incoordination of speech. Any or all of the normal motor structures may be involved. Unless a concomitant language disorder exists, a person with dysarthria has intact comprehension and is able to understand written, spoken, and read language. The most typical dysarthrias are summarized in Table 1. Table 1. Summary of Dysarthrias
The diagnosis of dysarthria is made clinically by assessing the pitch, nasality, articulation, rate, and intelligibility of the patient's speech. Additionally, each of the subsystems of speech (respiratory, laryngeal, pharyngeal, and oral structures) must be assessed. Bedside evaluation of dysarthria includes the following exercises:
SLPs can administer formal speech intelligibility tests, such as the Tikofsky word list or the Assessment of the Intelligibility of Dysarthric Speech. The overall goal in the treatment of dysarthria is functional communication in which a patient can reliably communicate basic needs of daily living. A generalized hierarchy of treatment moves through the following 3 stages, based on the severity of speech impairment:
Oral apraxia is an apraxia of nonverbal oral movements. Patients have difficulty performing movements such as sticking out their tongue, licking their lips, and protruding their lips. Lesions of the premotor cortex are a frequent finding in patients with this disorder. AOS is a disorder of articulation that encompasses the intonation, rhythm, and stress of speech (prosody). These patients find it difficult to accurately plan, initiate, and sequence speech movements. Typically, AOS occurs with left frontal lesions adjacent to the Broca area. The following characteristics usually are present:
Diagnosis is made clinically, based on the above characteristics. Additionally, AOS may be differentiated from dysarthria and aphasia, because in AOS, automatic speech, motor control, and other language modalities (ie, listening, reading, writing) are spared. A number of extensive objective tests exist and may be administered by the SLP to provide additional qualitative and quantitative information. Treatment of apraxia is designed to teach effective communication strategies and improve volitional control of the oral musculature. Exercises are used to teach sound sequencing, program sound patterns, and improve rhythm in speech. Language disorders (aphasia) Aphasia is a language disorder that results from damage to the areas of the brain responsible for language comprehension and expression.12 These injuries usually occur in the dominant side of the brain, which, for most people, is the left hemisphere. Depending on the site of the lesion, aphasia may involve spoken and written language expression, auditory comprehension, and reading and writing abilities.4 Aphasia may be described by a variety of abnormalities in speech production. Table 2 summarizes the terminology used to describe expressive disorders of aphasia. Table 2. Terminology Describing Expressive Disorders of Aphasia
Aphasias are classified in several ways. Traditionally, aphasia syndromes were classified as expressive or receptive. Individuals with expressive, or motor, aphasia had difficulty producing words and were believed to have a lesion in the Broca area in the dominant frontal lobe. Patients with receptive, or sensory, aphasia have difficulty comprehending language and are thought to have a lesion in the Wernicke area of the dominant temporal lobe. In the 1960s, a popular modification of the classification system was proposed based on the fluency, or rate of speech. Fluent speech is produced at normal to rapid rates and is effortless and well articulated. Nonfluent speech is slow, labored, and poorly articulated. As a rule, lesions anterior to the fissure of Rolando produce nonfluent aphasias; lesions posterior to this fissure produce fluent aphasias. Newer brain imaging techniques, however, have shown that subcortical and right hemispheric structures also contribute to language functions. The traditional classification systems are limited in that they classify the types of disorders according to the site of the lesion only in the dominant cortical hemisphere. The currently accepted classification system evaluates fluency, comprehension, and repetition; it also divides the aphasias into cortical and subcortical forms. Classification of the cortical aphasias is summarized in Tables 3 and 4. Table 3. Summary of Cortical Aphasias
Table 4. See Image 1. The advent of computed tomography (CT) scanning and magnetic resonance imaging (MRI) has enhanced our ability to identify small subcortical lesions as causes of aphasia.13, 14 The following 2 major forms of subcortical aphasias are recognized: (1) thalamic and (2) those due to lesions in the caudate, putamen, and/or internal capsule. Thalamic aphasia generally consists of fluent speech, mild impairment in comprehension, and intact repetition. Paraphasias, neologism, perseveration, and fluctuating attention are also common in thalamic aphasia. Lesions involving the putamen and caudate with extension into the internal capsule may cause several aphasic syndromes. The core syndrome is one of relative intact fluency, comprehension, and repetition. Depending upon the extent and location of the lesion, the syndrome may include better or worse articulation and comprehension, apraxia, and paraphasias. Evaluation of aphasia should be performed by the SLP using a formal standardized assessment of the components of language. Tests are designed to evaluate the patient's receptive and expressive language capacities by sampling components, such as conversational speech, comprehension, repetition, naming, reading, and writing. Several of the most commonly used aphasia batteries are summarized in Table 5.13, 14 Table 5. Comprehensive Tests for Aphasia
Successful treatment of aphasia is based on the detailed knowledge of a patient's cognitive and linguistic strengths and weaknesses obtained from the formal testing batteries. Traditional treatment strategies focused on syndrome-specific approaches, in which treatment is based on the diagnosed aphasia syndrome. More current strategies promote getting a message across by any means, that is, through language, gestures, drawing, or any other expressive method. Whatever strategy is employed, patients and families must be taught to maximize the individual's communicative strengths. Some treatment strategies are summarized in Table 6. Table 6. Methods of Treating Aphasia
See also the following related eMedicine topics: Aphasia Apraxia and Related Syndromes SELECTED COGNITIVE-COMMUNICATIVE DISORDERSSection 5 of 8
Cognitive-communicative disorders affect the ability to communicate by impairing the pragmatics, or social rules, of language. Cognitive processes involved include the following:
Cognitive-communicative impairments occur primarily with the following 3 conditions:
Patients with right hemispheric lesions have relatively intact language but demonstrate impaired overall communication abilities. Common deficits seen in right hemispheric lesions are visuospatial processing, insensitivity to context (missing subtleties), impulsivity, difficulty with expression and reception of emotions, lack of affective aspects (vocal inflection, facial expressions), impaired conversational rules (turn taking), left-sided neglect, poor topic maintenance (tangential), unawareness of deficits, and failure to recognize humor. These impairments often cause patients to be considered difficult to get along with, rude, indifferent, or depressed. Formal testing batteries for evaluating right hemispheric deficits can be administered by the SLP, including the RIC Evaluation of Communication Problems in Right Hemisphere Dysfunction (RICE) and the Mini Inventory of Right Brain Injury (MIRBI). Such batteries include analysis of the above deficits and assist the practitioner in deciding what treatment approaches to use. Treatment of right hemispheric dysfunction tends to focus on behavior modification. The goal of treatment is to improve a patient's understanding of the context and pragmatics of communication. Importantly, family training to allow adjustments to and understanding of the patient's new personality is paramount to rehabilitation success. Patients with TBI often show deficits in perception, language, and memory; therefore, all of these modalities should be evaluated. As patients recover, they generally demonstrate progressive improvement in cognitive functioning. Because recovery is a dynamic process, patients with TBI should be tracked serially by a neuropsychologist to help guide the treatment plan. Treatment of the cognitive-communicative deficits in patients with TBI requires special considerations. Most patients with TBI are aged younger than 30 years and have the potential to return to the workforce. Although initially the patient benefits from traditional rehabilitative techniques, he/she requires additional focus on areas of orientation, memory, attention, and self-regulation. Additionally, the patient's environment should be structured so that predictability reinforces memory. Lastly, generalization to real world settings is necessary during therapy if re-entry into the community is to be successful. Dementia results in generalized intellectual impairment that compromises communication ability. A result of diffuse, bilateral damage, dementia may be cortical and/or subcortical. The severity of language impairment is associated with impairment in other mental functions. Patients with dementia often are classified into the following stages:
Assessment of the demented patient should include a full history and physical examination, as well as formal testing. The Mini Mental Status examination can be administered quickly and easily. The SLP can administer the Arizona Battery for Communication Disorders of Dementia to assess communicative deficits. Assessment should be performed at regular intervals to follow the patient's progression. Dementia is progressive and diffuse; therefore, treatment is supportive. Treatment goals should include environmental controls, capitalization on any preserved memory, and family training. HEARING IMPAIRMENTSection 6 of 8
As mentioned earlier, the ability to hear is an integral part of the normal communication process. Impaired ability to relate to sounds can result in social isolation, depression, avoidance, and diminished quality of life. Frequencies used in the measurement of clinical hearing range from 250-8000 Hz. The most critical part of this spectrum is the range of frequencies used for the reception and understanding of speech, 400-4000 Hz. Conductive hearing loss results from dysfunction of the outer and/or middle ear. Patients with conductive hearing loss usually can understand (discriminate) speech correctly but require louder volumes of speech. Possible causes of conductive hearing impairment include cerumen impaction, presence of a foreign body, tympanic membrane perforation, otitis media, and otosclerosis. Sensorineural hearing loss results from dysfunction of the inner ear (cochlea) or neural fibers of the eighth cranial nerve. Patients with sensorineural hearing loss usually have decreased speech discrimination. Conditions causing sensorineural impairment include excess noise, advanced age (presbycusis), ototoxic drugs, viral or bacterial illness, tumors, and cortical lesions. A mixed hearing disorder involves components of conductive and sensorineural hearing loss. Central hearing impairment results from dysfunction of the central auditory pathways (eg, tumors, demyelinating disease, vascular damage). In general, conductive hearing is assessed by measuring sensitivity to sound waves vibrating through the air and moving from the external auditory canal and middle ear. Bone conduction is assessed by placing a vibrating tuning fork over the mastoid process. This maneuver bypasses the outer and middle ear and conducts sound vibrations directly to the cochlea. Therefore, it reflects the sensitivity of the sensorineural system. The most common rehabilitative therapy for hearing impairment is the hearing aid. Any person with hearing difficulties that limit daily activities should be considered a prospective candidate for a hearing aid. A hearing aid evaluation should be performed by a certified clinical audiologist. The use of a hearing aid does not cure the impairment, but it does improve the ability to communicate effectively. Successful hearing aid use is dependent on the patient's self-perceived impairment, acceptance of the device, and desire to use hearing amplification. Cochlear implants are auditory prostheses that provide hearing for the profoundly deaf. The implant converts sound into electrical signals that are delivered directly to any viable eighth-nerve neurons in the cochlea. Sounds perceived with a cochlear implant are entirely different from the amplified sound heard with a hearing aid. Assistive listening devices are used in selected listening environments. They employ a microphone placed close to the specific sound source, that transmits to the hearing-impaired listener. Assistive listening devices are effective in that they enhance the desired sound and diminish background noise. Other devices, such as closed-captioned television decoders, flashing alarms, telephone equipment, and tactile/vibration devices, are available. Auditory training teaches the patient to be an assertive listener. Patients are instructed to inform others as to their most effective means of communication. The hearing-impaired person also is trained to use speech reading (recognizing facial expressions, gestures) to improve understanding of speech. MULTIMEDIASection 7 of 8
REFERENCESSection 8 of 8
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