Speech Disorders

Definition

A speech disorder is a communication disorder characterized by an impaired ability to produce speech sounds or normal voice, or to speak fluently.

Description

Speech disorders belong to a broad category of disorders called communication disorders that also include language and hearing disorders. Communication disorders affect one person out of every ten in the United States. Speech disorders refer to difficulties producing speech sounds or problems with voice quality. They may be characterized by an interruption in the flow or rhythm of speech such as stuttering, or by problems with the way sounds are formed, also called articulation or phonological disorders, or they may involve voice problems such as pitch, intensity, or quality. Often, there is a combination of several different problems.

Speech disorders can either be present at birth or acquired as a result of stroke, head injury, or illness. The production of intelligible speech is the result of very complex interactions originating in the brain. When the brain sends a series of speech signals to the speech muscles, the muscles need to produce the series of sounds that will convey the intended message. Major speech disorders that can impair this process include:

• Articulation disorders: Articulation is the production of speech sounds, and persons affected by articulation disorders experience difficulty in being understood because they produce incorrect speech sounds. As a result, their speech is not intelligible. They may substitute one sound for another or may distort the sound with the result that it sounds incorrect, even though still recognizable, or omit one or more sounds in a word.
• Phonological disorders: Phonology is the science of speech sounds and sound patterns and of the language rules that dictate how sounds may be combined to produce language. Persons affected by phonological disorders do not use the conventional rules for their native language but substitute their own variants. This affects classes of sounds, as opposed to single sounds. Sounds are characterized by where in the mouth they are produced, how they are produced, and by how the larynx (voice box) is used. Any unusual deviation in these features is called a phonological process. Fronting and backing are examples of phonological processes, characterized by the production of sounds at the front or at the back of the mouth when they should be produced the other way around. For example, the word "go," produced at the back of the mouth, might be used instead of "doe," which is produced in the front.
• Stuttering: Normal speech is fluent, in that it is spoken effortlessly and without hesitation. A break in fluent speech is called a dysfluency. Although some degree of dysfluency occurs in normal speech from time to time, stuttering has more dysfluencies than is considered average. Normally developing preschool children often demonstrate dysfluencies that are effortless and last for brief periods of time. However, changes in the types of dysfluency behavior and the frequency of occurrence may signal the development of a problem. Normal dysfluencies consist of word or sentence repetitions, fillers (um, ah), or interjections. Stuttering behavior includes sound or syllable repetition, prolongations (the unnatural stretching out of sounds), and blocks, which refers to an inability to produce the sound, as if it gets stuck and cannot come out. Stuttering dysfluencies are also often accompanied by tension and anxiety.
• Voice disorders: There are two types of voice disorders: organic voice and functional voice disorders. Organic voice disorders are associated with disease and require medical intervention. Functional voice disorders are the result of abuse or misuse of the larynx. Sounds are produced when the vocal cords of the throat come close together and vibrate with air coming from the lungs. These vibrations produce a series of pulses that then cause the air to resonate and produce voice sounds. People have unique voice characteristics and it is therefore difficult to define a normal voice. Generally speaking, a normal voice is pleasant sounding and has appropriate pitch and loudness for the age and gender of the speaker. A voice disorder is therefore present when the voice is not pleasant sounding, or when it is too loud or too soft or too high-pitched or low-pitched for the speaker's gender.
• Apraxia: This is a speech disorder in which voluntary muscle movement is impaired without muscle weakness. There are two main types of apraxias: buccofacial apraxia and verbal apraxia. Buccofacial apraxia impairs the ability to move the muscles of the mouth for non-speech purposes such as coughing, swallowing, and wiggling of the tongue. Verbal apraxia impairs the proper sequencing of speech sounds. Apraxias can either be acquired or developmental and have different degrees of severity, ranging from the inability to initiate speech to mild difficulties with the pronunciation of multi-syllabic words.
• Dysarthria: This is a speech disorder that affects the muscles involved in the production of speech. As a result, speech is slow, weak, inaccurate, and hesitant. The production of clear speech requires that several muscle systems work together. First, the lungs must provide the air required to activate speech. Then, the larynx must allow the air to vibrate. The soft palate that separates the oral and nasal cavities must also direct the air to one or both cavities to produce the different sounds. Finally, the lips, tongue, teeth, and jaw then must all move in a concerted way to shape the sounds into the various vowels, consonants, and syllables that make up the sounds of language. Dysarthria results from a weakness in any one of these elements or in the absence of proper coordination between them. If, for example, the lungs are weak, then speech will be too quiet or produced one word at a time. Childhood dysarthria can be present at birth or acquired as a result of disease or accident, as is the case for adult dysarthria.

Causes and symptoms

The causes of articulation and phonological disorders are unclear, although it has been observed that they tend to develop in children before age four and run in families. The symptoms vary, depending on whether other disorders are present, but typically involve difficulty in making specific speech sounds. Articulation is considered a disorder when it is unintelligible or draws negative attention to the speaker. For example, the word "super" is pronounced as "thuper."

The causes of stuttering are not very well understood. There is some evidence that stuttering has a genetic cause since it has been observed to run in some families. According to the National Stuttering Association (NSA), current research suggests a connection between stuttering and the brain's ability to coordinate speech. The major symptom of stuttering, found in preschoolers but not adults, is persistent dysfluency of language that exceeds 10%.

The main causes of organic voice disorders include neuromuscular disorder, cancer, vocal cord paralysis, endocrine changes, various benign tumors such as inflammatory growths (granulomas), or consisting of amass of blood vessels (hemangiomas) or occurring on mucous membranes (papillomas). Functional voice disorders are caused by abuse or misuse of the larynx. Misuse of the voice includes talking for excessively long periods of time or yelling. Abuse occurs as a result of excessive throat clearing, laughing, crying, coughing, or smoking. Both abuse and misuse of the voice can damage the vocal cords, or may result in nodules, polyps, contact ulcers, or edema.

Acquired apraxias occur as a result of brain damage and can often be linked to specific lesion sites on the brain. They can result from stroke, head injury, brain tumors, toxins, or infections. In the case of developmental apraxia of speech (DAS), it is usually present at birth. There are no specific lesion sites in the brain associated with DAS, and no direct cause has been identified. However, since young children only use a few words, it has been proposed that delays in language expression can impair a child's ability to gain control over the speech muscles.

Childhood dysarthria can be present at birth or acquired with diseases such as cerebral palsy, Duchenne muscular dystrophy, or myotonic dystrophy. Adult dysarthria may be caused by stroke, degenerative diseases such as Parkinson's or Huntington's disease, amyotrophic lateral sclerosis, multiple sclerosis, myasthenia gravis, meningitis, brain tumors, toxins, drug or alcohol abuse, or lead poisoning.

Diagnosis

Speech disorders are usually identified using a combination of hearing tests and physical exams. Physicians then recommend specialized evaluation by speech-language pathologists, who can best establish an accurate diagnosis.

A stuttering diagnosis is established on the basis of the type, frequency, and duration of speech dysfluency. The number of dysfluencies occurring in 100 words is counted to determine the dysfluency percentage. One half a stuttered word per minute is the usual criterion. Determining the type of stuttering behavior, either overt or covert, is the most important factor in diagnosing stuttering.

Organic and functional voice disorders are diagnosed with the assistance of an ear, nose, and throat specialist, an otolaryngologist, who can identify the organic cause of the voice disorder, if present. Several tests can be used to screen for possible tumors in the throat or laryngeal box area. Only in the absence of an organic cause will the voice disorder be diagnosed as functional, indicating that it is due to abuse or misuse of the voice.

A diagnosis of apraxia is not easy to establish but is usually indicated when children do not develop speech normally and are unable to produce consonant sounds.

Treatment

Speech pathologists have designed approaches for treating speech disorders with the type of treatment depending upon the type of impairment. A wide variety of treatment techniques are available for treating affected children, adolescents, and adults. A thorough assessment is normally conducted with the aim of determining the most effective and acceptable treatment approach for each disorder on an individual basis. A common treatment for many patients involves increasing sensory motor awareness of selected aspects of speech and systematically shaping the target speech behaviors.

Treatment for articulation/phonological disorders is usually based on increasing the affected person's awareness about how speech sounds make the meaning of words different. As a result, therapy often involves pronunciation exercises designed to teach how to produce sounds and words more clearly to increase understanding of the differences between the various speech sounds and words.

Treatment plans for stuttering depend on the severity of the dysfluency and may include seeing a speech-language pathologist. Most treatment plans include breathing techniques, relaxation strategies to help relax speech-associated muscles, posture control, and other exercises designed to help develop fluency.

Speech-language pathologists use many different approaches to treat voice problems. Functional voice disorders can often be successfully treated by voice therapy. Voice therapy involves identifying voice abuses and misuses and designing a course of treatment aimed at eliminating them. Voice disorders may require surgery if cancer is present.

Treatment of apraxia depends on the extent of the impairment. For individuals diagnosed with moderate to severe apraxia, therapy may be for them to start saying individual sounds and contrasting them, thinking about how the lips and tongue should be placed. Other specialized drills use the natural rhythm of speech to increase understanding. Individuals affected with mild apraxia are taught strategies to help them produce the words that give them difficulty. Several treatment programs have been developed for developmental apraxias. Some feature the use of touching cues, others modify traditional articulation therapies.

Treatment of dysarthria usually aims at maximizing the function of all speech systems with the use of compensatory strategies. Patients may be advised to take frequent pauses for breath, or to exaggerate articulation, or to pause before important words to emphasize them. If there is muscle weakness, orofacial exercises may also be prescribed to strengthen the muscles of the face and mouth that are used for speech.

Prognosis

The prognosis depends on the cause of the disorder; many speech disorders can be improved with speech therapy. In the case of childhood speech disorders, prognosis also significantly improves with early diagnosis and intervention. Children who do not receive speech therapy and do not outgrow their speech difficulties will continue to have the disorder as adults.

Health care team roles

The treatment of speech disorders belongs to the field of speech-language pathology. Speech-language pathologists assist individuals who have speech disorders and collaborate with families, teachers, and physicians to design an appropriate course of treatment, which depends on the specific nature of the disorder. They also provide individual therapy to affected persons, consult with teachers about effective classroom strategies to help children with speech disorders, and work closely with families to develop effective therapies.

Prevention

Prevention of speech disorders is centered on identifying at-risk infants. The following conditions are considered to represent high-risk factors, and children exposed to them should be tested early and regularly:

• diagnosed medical conditions such as chronic ear infections
• biological factors such as fetal alcohol syndrome
• genetic defects such as Down syndrome
• neurological defects such as cerebral palsy
• family history such as family incidence of literacy difficulties

Stuttering can be prevented by parents avoiding undue corrections of dysfluency in their children. As young children begin to speak, some dysfluency is normal because they have a limited vocabulary and have difficulty expressing themselves. This results in dysfluent speech, and if parents place excessive attention on the dysfluency, a pattern of stuttering may develop. Speech therapy with children at risk for stuttering may prevent the development of a stuttering speech disorder.

KEY TERMS

Apraxia— Motor disorder in which voluntary movement is impaired without muscle weakness.

Articulation disorder— Also called phonological disorder; type of speech disorder characterized by the way sounds are formed.

Communication disorder— Disorder characterized by an impaired ability to communicate, including language, speech, and hearing disorders.

Dysarthria— Speech disorder due to a weakness or lack of coordination of the speech muscles.

Dysfluency— Any break or interruption in speech.

Language disorder— Communication disorder characterized by an impaired ability to understand and/or use words in their proper context, whether verbal or nonverbal.

Phonological process— Any unusual change in the place, manner, or larynx characteristics of a produced sound.

Phonology— The science of speech sounds and sound patterns.

Speech disorder— Communication disorder characterized by an impaired ability to produce speech sounds or by problems with voice quality.

Speech-language pathology— This field, formerly known as speech therapy, is concerned with disorders of speech and language.

Stuttering— Speech disorder characterized by speech that has more dysfluencies than is considered average.

Vocal cords— Either of the two pairs of folds of mucous membrane located in the throat and projecting into the cavity of the larynx.

Resources

BOOKS

Dworkin, J. P., and R. J. Meleca. Vocal Pathologies: Diagnosis, Treatment, and Case Studies. San Diego, CA: Singular Publishing Group, 1997.

Golding-Kushner, K. J. Therapy Techniques for Cleft Palate Speech and Related Disorders. San Diego, CA: Singular Publishing Group, 2001.

Kehoe, T. D. Stuttering: Science, Therapy, & Practice: The Most Complete Book about Stuttering. Boulder, CO: Casa Futura Technologies, 1997.

PERIODICALS

Johnson, N. C., and J. R. Sandy. "Tooth Position and Speech—Is There a Relationship?" Angle Orthodentistry 69 (August 1999): 306-10.

Kraus, N., and M. Cheour. "Speech Sound Representation in the Brain." Audiology and Neurotology 5 (May-August 2000): 97-132.

Oller, D. K., R. E. Eilers, A. R. Neal, and H. K. Schwartz. "Precursors to Speech in Infancy: The Prediction of Speech and Language Disorders." Journal of Communication Disorders 32 (July-August 1999): 223-45.

Postma, A. "Detection of Errors during Speech Production: A Review of Speech Monitoring Models." Cognition 77 (November 2000): 97-132.

Rosen, C. A., and T. Murry. "Nomenclature of Voice Disorders and Vocal Pathology." Otolaryngology Clinical North America 33 (October 2000): 1035-46.

ORGANIZATIONS

American Speech-Language-Hearing Association (ASHA). 10801 Rockville Pike, Rockville, MD 20852. 800) 638-8255.〈http://www.asha.org/〉.

Autism Society of America. 7910 Woodmont Avenue, Suite 300, Bethesda, MD 20814-3067. (301) 657-0881. (800) 3AUTISM. 〈http://www.autism-society.org/〉.

The Hanen Program for Parents of Children with Language Delays. The Hanen Center, Suite 403, 1075 Bay Street, Toronto, Ont M5S 2B1, Canada. (416) 921-1073. 〈http://www.hanen.org/〉.

National Institute on Deafness and Other Communication Disorders (NIDCD). National Institutes of Health, 31 Center Drive, MSC 2320, Bethesda, MD 20892-2320. 〈http://www.nidcd.nih.gov/〉.

OTHER

"Center for Voice Disorders of Wake Forest University." Wake Forest University School of Medicine. 〈http://www.bgsm.edu/voice/〉.

"A Guide to Communication Disorders and Science Sources on the Internet." Net Connections for Communication Disorders and Sciences. 〈http://www.mankato.msus.edu/dept/comdis/kuster2/welcome.html〉.

"The SLP Homepage." Internet Searches and Resources on Speech Language Pathology. 〈http://members.tripod.com/Caroline_Bowen/slp-eureka.htm〉.

Speech Disorders

How Does Speech Develop?

What Can Go Wrong?

Articulatory Disorders

Brain Disorders

How Are Speech Disorders Diagnosed and Treated?

Resources

A speech disorder is a condition that interferes with a persons ability to speak clearly and understandably. It may be caused by developmental delays, hearing problems, accidents, strokes, or defects in any of the organs or muscles involved in producing speech or in any of the areas of the brain that control speech.

KEYWORDS

for searching the Internet and other reference sources

American Sign Language

Aphasia

Articulation

Augmentative communication devices

Broca’s area

Communication disorders

Neurology

Stuttering

Wernicke’s area

How Does Speech Develop?

Speech and language develop most intensively during the first three years of life. When babies are born, they can make sounds by pushing air out of the lungs and through the vocal cords in the throat. The air vibrates these vocal cords, located in the larynx (LAR-inks) or voice box, creating sound.

Newborns learn that a cry will bring food, comfort, and companionship, and they begin to recognize certain sounds. As the jaw, lips, tongue, throat and brain develop over the first nine months of life, infants learn how to use the voice to mimic simple controlled sounds, such as “ba ba” or “da da.” During this time, they learn to regulate the action of muscles in the face, mouth, neck, chest, and abdomen to produce speech-like sounds. At first, these sounds are filled with nonsense syllables. Eventually, children begin to use words that others can understand. The responses they get encourage them to speak more and more. With practice, words become more understandable.

During the preschool years, children increase their mastery of speech sounds, word and sentence formation, word and sentence understanding, the tone and rhythm of speech, and effective use of language.

What Can Go Wrong?

Speech disorders arise from many different conditions and have a wide range of causes. Two main parts of the brain are involved in producing and understanding speech: Brocas area and Wernicke’s area. Broca’s area coordinates the muscles of the lips, tongue, jaw, and vocal cords to produce understandable speech. Wernicke’s area controls the comprehension, or understanding, of others’ speech. Damage to these or other portions of the brain—or to the nerve connections to the organs that make speech (tongue, mouth, chest, and so forth)—can result in disordered speech.

Stroke, trauma, or infection may be the root cause of these disruptions. Severe mental retardation often has a negative impact on speech development. In some cases, anatomy plays a role in speech disorders, for example cleft palate, cleft lip, hearing problems, and damage to the larynx all can interfere with speech.

Speech disorders are fairly common in children. Many children show delays in developing speech, a condition that frequently is outgrown. Often the cause of a child’s speech disorder is never known.

When adults develop a speech disorder after years of speaking normally, it usually is easier to locate the cause. For instance, a stroke, head injury, brain tumor, or dementia* may involve damage to the areas of the brain that affect speech or speech understanding. In other cases, an accident, a surgical procedure, or a viral infection can cause damage to the nerves that control the functions of the larynx.

* dementia

(de-MEN-sha) is a general loss of intellectual abilities involving impairment of memory, judgment and abstract thinking, and often changes in personality.

Articulatory Disorders

Articulatory (ar-TIK-yoo-la-tor-ee) disorders interfere with the process whereby the muscles of the mouth, tongue, jaw, throat, and diaphragm work together to produce clear, understandable sounds. These problems typically begin in childhood and can persist into adulthood. They also may be called fluency disorders.

It is normal for children to have problems with articulation as they are learning to speak. For instance, many children between the ages of 2 and 3 are unable to pronounce the sound “th.” Other children in this age group stutter, which means that they repeat sounds occasionally or hesitate between words. Most children outgrow such problems rather quickly. If problems persist, however, they are considered speech disorders.

Lisp

A lisp is a relatively common speech disorder in which a person has trouble pronouncing the sounds of the letters “s” and “z.” One of the most well-known lispers is the cat, Sylvester, featured in the Tweety Bird cartoons, whose favorite exclamation is “thuffering thuccotash!”

Lisping can happen for a variety of reasons: an abnormal number or position of teeth; unconscious imitation of other lispers; defects in the structure of the mouth, such as a cleft palate; or hearing loss. Usually lisps can be corrected by working with a speech-language therapist who coaches the person with the lisp to make the sound correctly.

Stuttering

Stuttering often begins in early childhood and may persist into adulthood. People who stutter repeat certain speech sounds, or prolong certain sounds, or hesitate before and during speaking. Stuttering often is referred to as a fluency disorder because it disrupts the smooth flow of speech. Over 3 million Americans stutter, and most began stuttering between the ages of 2 and 6.

Stuttering can have social and emotional consequences. People who stutter may be self-conscious about their speech. Some show signs of tension, such as twitching, unusual facial expressions, or eye blinks, when trying to get words out. Experts are not sure what causes stuttering, although some studies show that stuttering has a tendency to run in families, suggesting that it may have a genetic component.

Other cases of stuttering may be neurogenic (noor-o-JEN-ik), meaning that that they are caused by signal problems between the brain and the nerves or muscles that control speech. Stuttering also may result from emotional trauma, stress, or other psychological causes.

Researchers have found that stuttering affects males about four times more often than females. Certain situations, such as speaking before a group

Sign Languages

Spoken language is not the only way that people can communicate. Many people who are deaf and/or unable to speak learn to communicate through manual communication or signed language. Currently, there are three signed languages used in the United States.

In the mid-1 700s, a French educator working with poor deaf children developed a system for spelling out French words with a manual alphabet, expressing whole concepts with one or two hand signs, and adding emphasis with standardized facial expressions. In 1816, Thomas Gallaudet (1787-1851) brought French Sign Language to the United States. French Sign Language was modified to incorporate English terms, while maintaining French sentence structure, to form what now is American Sign Language (ASL). Gallaudet University in Washington, D.C., is named for Thomas Gallaudet.

Signed Exact English was developed by educators in California who worked with children with hearing loss and deafness. This language takes the same alphabet and hand signs as American Sign Language, but places them into English sentence structure.

Cued Speech, developed in 1966 by the American scientist R. Orin Cornett, uses hand signs to represent sounds, rather than letters or concepts. It is used in conjunction with mouthing of word cues, such as the most prominent vowel in each word.

of people or talking on the telephone, may make stuttering more severe for some, whereas singing or speaking alone often improve fluency.

Successful Speakers

What do singers Carly Simon and Mel Tillis, television journalist John Stossel, and actors James Earl Jones, Marilyn Monroe, and Bruce Willis have in common? All share the problem of stuttering. Their public successes point to one of the unique features of stuttering: although it is a problem in everyday conversation, often it disappears when someone is singing or delivering memorized lines. Further, people who stutter often can learn strategies for overcoming the problem as they grow older.

James Earl Jones

In his autobiography, actor James Earl Jones describes how he overcame his stuttering problem by reading Shakespeare aloud to himself and then reading to audiences, debating, and acting. Jones has provided the voices for Darth Vader in Star Wars and King Mufasa in the animated Lion King, and has acted on stage and in numerous films.

John Stossel

As a reporter for the television news magazine 20/20, John Stossel depends on his voice to make a living. He stuttered as a child and worked hard to hide the condition. Stossel started his career in news as a researcher, but eventually was asked to go on the air. He considered quitting when he found himself stumbling over certain words, but he got help overcoming his stuttering through speech therapy at the Hollins College speech clinic in Roanoke, Virginia. Stossel now is a spokesman for the National Stuttering Association.

Most young children outgrow their stuttering, and it is estimated that fewer than 1 percent of American adults stutter. However, children who do not outgrow stuttering by the time they enter elementary school may need speech therapy. Many people have overcome stuttering and gone on to achieve success in careers that require public speaking, acting, and singing.

Brain Disorders

Speech disorders in adults usually are the result of damage to the portions of the brain that control language. Damage may be caused by head injury, brain tumor, or Stroke. Adults who have aphasia (a-FAY-zha) not only have trouble speaking, but also have difficulty understanding what others are saying. Dysphasia (dis-FAY-zha) is a condition that causes similar, but less severe, challenges in speaking and understanding. The symptoms of aphasia and dysphasia depend on which area of the brain is affected: Brocas area or Wernicke’s area.

Broca’s aphasia

Brocas aphasia results from damage to the area that coordinates the muscles of the lips, tongue, jaw, and vocal cords that produce understandable speech. People with damage to Broca’s area frequently speak in short, meaningful phrases that are produced with great effort, omitting small words such as “is,” “and,” and “the.” People with Broca’s aphasia often are aware of their speech difficulties and may become frustrated by their speech problems.

Wernicke’s aphasia

Wernicke’s aphasia results from damage to the area of the brain responsible for understanding speech. These people have trouble understanding others and often are unaware of their own problems. They may speak in long rambling sentences that have no meaning, often adding unnecessary words. They may even create nonsense words.

Global aphasia

Global aphasia results from damage to large portions of the language areas of the brain. Individuals with global aphasia have severe communication difficulties and may be extremely limited in their ability to speak or to comprehend language.

How Are Speech Disorders Diagnosed and Treated?

Diagnosis

Many adults recognize when they develop a speech difficulty and seek help from doctors and trained speech-language therapists. Parents of children with speech disorders often are the first to call the condition to the attention of health care providers.

Speech-language therapists often make an initial evaluation to help determine what problems exist and the best way to treat them. Because talking and hearing are closely related, children with speech disorders often undergo a hearing evaluation done by an audiologist (aw-dee-OL-o-jist), who is educated in the study of the hearing process and hearing loss. The audiologist can determine if a person has a hearing loss, the type of loss, and recommend how the person can make the best use of any remaining hearing. When the speech disorder is caused by damage to the nerves or brain, a neurologist may also be involved in the evaluation process.

Treatment

People with aphasia often benefit from speech-language therapy, which focuses on helping people make the most of their remaining abilities and learning other methods of communicating. Supplemental methods of communication that assist an individual in speaking are called Augmentative Communication Devices (ACDs). Available ACDs include portable communication computers, personalized language boards, and picture exchange programs. As technology continues to improve and become more portable, communication possibilities for aphasic and dysphasic adults will continue to expand.

See also

Deafness and Hearing Loss

Infection

Laryngitis

Mental Retardation

Stroke

Trauma

Resources

Books

Bobrick, Benson, and Deborah Baker, Eds. Knotted Tongues: Stuttering in History and the Quest for a Cure. New York: Kodansha, 1996.

Jezer, Marty. Stuttering: A Life Bound Up in Words. New York: Basic Books, 1997.

Organizations

U.S. National Institute on Deafness and Other Communication Disorders, National Institutes of Health, 31 Center Drive, MSC 2320, Bethesda, MD 20892-2320. Telephone 800-241-1044 http://www.nih.gov/nidcd

American Speech-Language-Hearing Association (ASHA), 10801 Rockville Pike, Rockville, MD 20852. Telephone 888-321-ASHA http://www.asha.org

National Aphasia Association, 156 Fifth Avenue, Suite 707, New York, NY 10010. Telephone 800-922-4622 http://www.aphasia.org

National Stuttering Project, 5100 East LaPalma Avenue, Suite 208, Anaheim Hills, CA 92807. Telephone 800-364-1677 http://www.nspstutter.org

Stuttering Foundation of America, P.O. Box 11749, 3100 Walnut Grove Road, Number 603, Memphis, TN 38111. Telephone 800-992-9392 http://www.stuttersfa.org

Speech Disorders

Definition

According to the American Speech-Language-Hearing Association (ASHA), a language disorder is an impairment in comprehension use of the spoken, written, or other symbol system.

Description

Speech disorders affect the language and mechanics, the content of speech, or the function of language in communication. Because speech disorders affect a person's ability to communicate effectively, every aspect of the person's life can be affected, for example, the person's ability to make friends, and to communicate at school or at work.

Amyotrophic lateral sclerosis (ALS)

Amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's disease, is a neurological disease that attacks the nerve cells in the brain that control voluntary muscles. ALS causes motor neurons to die so that the brain and spinal cord are unable to send messages to the muscles telling them to move. Because the muscles are not functioning, they begin to atrophy. Muscles in the face and jaw can be affected, and thereby affecting a person's speech.

Aphasia

Aphasia results from damage to the language centers of the brain, which affects a person's ability to communicate through speaking, listening, and writing.

Persons with aphasia have trouble with expressive language, what is said, or receptive language, what is understood. Not only are speech and understanding speech affected, but also reading and writing is affected. The severity of aphasia varies from person to person, but in the most severe cases, a person may not be able to understand speech at all. Persons with mild aphasia may only become confused when speech becomes lengthy and complicated.

Developmental apraxia of speech

Developmental apraxia is a disorder that affects the nervous system and affects a person's ability to sequence and say sounds, syllables, and words. The brain does not send the correct messages to the mouth and jaw so that the person can say what he or she wants to say.

Children who are suffering from this disorder don't babble as an infant and first words are delayed. Older children may have more difficulty with longer phrases, and may appear to be searching for words to express a thought. Listeners will likely have a difficult time understanding the child.

Laryngeal cancer

Laryngeal cancer is characterized by a malignant growth in the larynx, or the voice box, which sometimes requires removal of the larynx or part of it.

Cancer anywhere in the throat affects speech, swallowing, and chewing. Depending on the size of the growth, a person may have trouble moving the mouth and lips. Therefore, speech sounds and eating will be affected and a person will have trouble communicating.

Orofacial myofunctional disorders

Orofacial myofunctional disorder (OMD) causes the tongue to move forward in an exaggerated manner while a person is speaking or swallowing. The tongue also may protrude when resting in the mouth.

Because heredity contributes to the size and shape of a person's mouth, there may be genetic reasons for the disorder. Allergies also affect the mouth and face muscles, which make it difficult to breathe because of nasal congestion. Because a person may sleep with the tongue protruding, lip muscles weaken. Enlarged tonsils also can block airways, creating the same breathing problems. Additionally, thumb-sucking, nail-biting, and teeth-clenching and grinding also can contribute to the disorder.

Stuttering

Stuttering is a disorder of speech fluency that frequently interrupts the flow of speech.

Because children typically stumble and confuse their words as speech develops, stuttering is not immediately evident. It is usually when children become older and continue to stumble that stuttering becomes evident.

Causes and symptoms

Amyotrophic lateral sclerosis (ALS)

Initial symptoms include weakness in any part of the body, and appendages begin to tire easily. Occasionally the disease affects only one appendage rather than both at the same time. Persons with ALS may have trouble maintaining balance and may stumble or have difficulty with tasks that require manual dexterity, such as buttoning a shirt or tying a shoe.

Eventually, the diaphragm and chest wall become so weak that a person cannot breathe on his or her own and needs the help of a ventilator. Because of the lack of muscle strength, a person with ALS will experience difficulty speaking loudly and clearly until the person is unable to speak at all using the vocal cords. The person will have difficulty pronouncing words and have difficulty completing lengthy sentences.

Along with the difficulty in speaking also comes difficulty in chewing and swallowing. Food can be broken down and pureed to make it easier to chew and swallow. However, a person eventually will have difficulty chewing and swallowing foods that are broken down or pureed. When ability to eat is affected, proper nutrition and body weight also are affected, and medical professionals may decide that it is best to put in a feeding tube.

Aphasia

Stroke is the most common cause of aphasia, although other injuries, such as a brain tumor or gunshot wound, also can cause aphasia.

Developmental apraxia of speech

Developmental apraxia is a disorder that affects the nervous system and affects a person's ability to sequence and say sounds, syllables, and words. The brain does not send the correct messages to the mouth and jaw so that the person can say what he or she wants to say.

Children who are suffering from this disorder don't babble as an infant and first words are delayed. Older children may have more difficulty with longer phrases, and may appear to be searching for words to express a thought. Listeners will likely have a difficult time understanding the child.

There is no known cause for developmental apraxia of speech. Symptoms include weakness of the jaw, tongue, and lips, and delayed speech development. Persons with the disorder also may have trouble identifying an object in the mouth using the sense of touch, which is known as oral-sensory perception.

Laryngeal cancer

Any kind of smoking of cigarettes, cigars, or tobacco and alcohol abuse contribute to oral cancer, including smokeless tobacco. Persons with laryngeal cancer or another type of oral cancer may have a red or white patch or lump in the mouth. Symptoms also include difficulty chewing, swallowing, or chewing.

Stuttering

There is no known cause for stuttering, although poor muscle coordination and the rate of language development are believed to contribute to it.

Stuttering is characterized by repetition of sounds, syllables, portions of a word, words, and complete phrases; stretching the sounds and syllables; hesitation between words; words spoken in spurts; tense muscles in the jaw and mouth; and a feeling of loss of control.

Diagnosis

Amyotrophic lateral sclerosis (ALS)

About 20,000 people in the United States have ALS at any given time with 5,000 new cases diagnosed every year. ALS is in the same family of disorders as multiple sclerosis, Parkinson's disease, and muscular dystrophy. Persons of all races and ethic groups are afflicted by the disease, although men are more likely to have it than women.

Aphasia

About 700,000 persons in the United States have strokes every year, and one million are estimated to have aphasia.

Developmental apraxia of speech

A child suspected to have apraxia should first have his or her hearing tested to determine if the child has any deafness. Muscle development in the face and jaw should be evaluated and speech exercises tested. Articulation of words should be tested as well as the person's expressive and receptive language skills.

Laryngeal cancer

It is likely that a dentist or physician will first detect signs of possible cancer. Oral cancer makes up about 2-5% of all cancers, and about 30,000 cases are diagnosed each year. Twice as many men than women are diagnosed with cancer typically between the ages of 50 and 70.

Orofacial myofunctional disorders

The diagnosis of orofacial myofunctional disorder affects speech sounds because of weak tongue tip muscles, although a person's speech may not be affected at all.

Stuttering

Stuttering is a problem that most likely will manifest itself during childhood rather than adulthood.

Treatment

Amyotrophic lateral sclerosis (ALS)

In addition to treatments such as a feeding tube, a person with ALS would likely enlist the help of a speech therapist to help him or her determine ways in which he or she can maintain vocal control. A person also may enlist the help of an occupational therapist, a medical professional trained to help persons who have trouble with activities of daily living such as dressing, bathing, and eating.

Aphasia

A speech-language pathologist can perform drills and exercises with a person that include practice in naming objects and following directions to try to improve skills. The person learns the best way to express himself of herself. Group therapy also is an option, which focuses on structured discussions.

Developmental apraxia of speech

Treatment should focus on the coordination of motor movements necessary during speech production, which includes controlling breathing. A speech-language pathologist teaches exercises to a person with apraxia that will strengthen the jaws, lips, and tongue to improve coordination during speech. The therapist uses tactile, auditory, and visual feedback to direct the brain to move the muscles used during speech.

Laryngeal cancer

Depending on when the cancer is first detected, and depending on the size of the cancer, the entire larynx may not need to be removed. Radiation, chemotherapy, or partial removal can be done in lieu of complete removal. In these cases, the voice may be preserved although the quality likely will be affected.

Orofacial myofunctional disorders

In cases where speech is affected, a speech pathologist should be consulted to help control breathing problems and work on speech articulation. The lip, palate, tongue, and facial muscles should be evaluated so that errors in speech can be detected. Therapy includes increasing awareness of the mouth and facial muscles, as well as the posture of the mouth and tongue. Muscle exercise can be done to increase strength and control.

Stuttering

A treatment plan by a speech therapist includes improving fluency and ease with which a person speaks. Strategies include reducing the rate of speech and using slower speech movements; articulating lightly; and starting air flow for speech before any other muscle movement.

Alternative treatment

Developmental apraxia of speech

Some persons with apraxia may decide to use alternative communication systems, such as a computer that transcribes and "speaks" what a person is directing it to say. These augmentative systems should only be used when a person is so severely impaired that effective speech or communication isn't possible.

Laryngeal cancer

In cases of a full laryngectomy, a hole is made in the neck and, rather than using the mouth and nose to talk and breath, the person must use the hole.

Once the larynx is removed, the person needs to develop a new speech system without a voice. A speech pathologist should follow one of three plans: esophageal speech, artificial larynx, or tracheoesophageal puncture (TEP).

• Esophageal speech. Without a larynx, a person is no longer able to exhale air from the lungs through the mouth to speak. Using esophageal speech, the person inhales and traps the air in the throat, causing the esophagus to vibrate and create sound.
• Artificial larynx. A mechanical instrument can be used that produces sound for some speech. These devices can be held against the neck or used by inserting a tube in the mouth.
• Tracheoesophageal puncture. This is a popular method in restoring speech production. During surgery, a hole is made between the trachea and esophagus and a valve is inserted into the hole. The person breathes air into the lungs and then covers the hole in the throat. During exhalation, the esophagus vibrates and creates speech.

Stuttering

A person suffering from stuttering may employ distraction strategies to help him or her stop stuttering. Typically, a person stuttering becomes frustrated and embarrassed; subsequently, encouraging the person to think of something or do something else may break the stuttering cycle.

Prognosis

Amyotrophic lateral sclerosis (ALS)

ALS patients often die of respiratory failure within three to five years of being diagnosed, although some persons have been known to survive as many as 10 years or longer.

Aphasia

Persons with aphasia can improve and eventually function in more typical public settings, and possibly return to school or work.

Developmental apraxia of speech

With proper treatment, apraxia can be brought under control and the person will be able to function normally as an adult.

Laryngeal cancer

Full removal of the larynx removes the risk of a cancer relapse, although other parts of the throat and mouth can be affected.

Orofacial myofunctional disorders

A person can learn to control this disorder with proper treatment and maintain normal speech and breathing patterns.

Stuttering

With proper speech therapy, stuttering can be controlled or eliminated.

Prevention

Laryngeal cancer

Persons should not engage in smoking or drug abuse to decrease the risk of oral cancer.

Orofacial myofunctional disorders

In cases where the cause is evident, such as allergies or enlarged tonsils, a person should first remedy that problem; perhaps have the tonsils removed and treat allergies with medication.

Resources

BOOKS

Paul, Rhea. Language Disorders from Infancy through Adolescence. 2nd ed. St. Louis: Mosby, Inc., 2001.

ORGANIZATIONS

American Speech-Language-Hearing Association. 1801 Rockville Pike, Rockville, MD 20852. (800) 638-8255. 〈http://www.asha.org〉.

KEY TERMS

Neurons— Nerve cells in the brain, brain stem, and spinal cord that connect the nervous system and the muscles.

Speech disorders

Definition

Speech disorders are characterized by a difficulty in producing normal speech patterns.

Description

Children go through many stages of speech production while they are learning to communicate. What is normal in the speech of a child of one age may be a sign of a problem in an older child. Speech disorders include voice disorders (abnormalities in pitch, volume, vocal quality, resonance, or duration of sounds), articulation disorders (problems producing speech sounds), and fluency disorders (impairment in the normal rate or rhythm of speech, such as stuttering .

Demographics

Speech disorders are common. More than a million children in the public schools' special education programs have been diagnosed with a speech disorder. One in 10 people in the United States is affected by a communication disorder (speech, language, or hearing disorders).

Causes and symptoms

The causes of most speech disorders are not known. Deafness and hearing loss are significant causes of speech delays and disorders. The symptoms of a speech disorder depend heavily on the age of the child. There are no symptoms of speech disorders that apply to all ages of children. Basic guidelines about what kind of speech is normal at what age can be helpful in determining if a child is missing significant speech milestones.

• Twelve months: By this time babies should respond nonverbally, have different types of cries, and may know one or a few simple words (e.g. "mama" or "dada"). At this age babies should coo and babble.
• Eighteen months: Children of this age should be increasing their vocabularies slowly and be able to produce five to 20 common words.
• Twenty-four months: At this point vocabulary building should begin to speed up. At this age children should be able to produce simple sentences made up of two words.
• Three years: Children should begin to be able to produce speech that is understood by those outside immediate caretakers. Sentences become longer and more complex, and vocabulary increases drastically.

When to call the doctor

If a child continuously misses speech milestones, or is significantly behind what is generally considered average for his or her age, a doctor should be consulted. If hearing loss is ever suspected, such as if a child only responds when the parent speaking is in eyesight, the doctor should be consulted without delay.

Diagnosis

A doctor will do a hearing test on the child to ensure that a hearing problem is not responsible for the speech delay. The doctor may interact with the child to determine linguistic competence. In addition, he or she will interview the parents or other caregivers or have them fill out a list indicating the child's verbal skills. The doctor will typically refer the child to a speech pathologist—a professional specializing in treating speech problems. The speech pathologist will work with the child, the child's family , and any other caregivers to develop a plan to help the child.

Treatment

Children with isolated speech disorders are often helped by articulation therapy, in which they practice repeating specific sounds, words, phrases, and sentences. For stuttering and other fluency disorders, a popular treatment method is fluency training, which develops coordination between speech and breathing, slows down the rate of speech, and develops the ability to prolong syllables. A child may practice saying a single word fluently and then gradually add more words, slowly increasing the amount and difficulty of speech that can be mastered without stuttering. The speaking situations can gradually be made more challenging as well, beginning with speaking alone to the pathologist and ending with speaking to a group of people.

Delayed auditory feedback (DAF), in which stutterers hear an echo of their own speech sounds, has also been effective in treating stuttering. When a speech problem is caused by serious or multiple disabilities, a neurodevelopmental approach, which inhibits certain reflexes to promote normal movement, is often preferred. Other techniques used in speech therapy include the motor-kinesthetic approach and biofeedback, which helps children know whether the sounds they are producing are faulty or correct. For children with severe communication disorders, speech pathologists can assist with alternate means of communication, such as manual signing and computer-synthesized speech.

Prognosis

When speech disorders are detected and treated early, the prognosis is generally very good. Many speech disorders that are not caused by other underlying problems resolve themselves, and most others can be resolved completely or nearly completely with prompt treatment. Stuttering resolves itself without treatment in about 50–80 percent of children.

Prevention

There is no known way to prevent most speech disorders, although making sure that children have a language-rich environment is thought to help disorders related to lack of input.

Parental concerns

Speech disorders and significant speech delays can have a lasting negative impact on children. Children who have speech disorders may not want to communicate with their peers or even adults which may adversely affect their performance in school and social development.

KEY TERMS

Speech pathologist —An individual certified by the American Speech-Language-Hearing Association (ASHA) to treat speech disorders.

See also Language delay; Language disorders.

Resources

BOOKS

Bahr, Diane Chapman. Oral Motor Assessment and Treatment: Ages and Stages. Boston: Allyn and Bacon, 2001.

Freed, Donald B. Motor Speech Disorders: Diagnosis & Treatment. San Diego: Singular Pub. Group, 2000.

Merritt, Donna D. and Barbara Culatta. Language Intervention in the Classroom. San Diego, Calif.: Singular Pub. Group, 1998.

ORGANIZATIONS

American Speech-Language-Hearing Association. 10801 Rockville Pike, Rockville, MD 20852. (800) 638–8255. Web site: <www.asha.org>.

Tish Davidson

Echolalia

Repetition of another person's words or phrases.

Using a mechanical, robot like speech pattern, an individual with certain mental disorders may repeat words or phrases spoken by others. Known as echolalia, this behavior is observed in children with autism , Tourette's syndrome, schizophrenia , and certain other brain disorders.