Language Impairments: Causes and Prevention

Causes

Speech impairments can result from many different conditions, including brain damage, malfunction of the respiratory or speech mechanisms, and malformation of the articulators. Some children make articulation errors because they do not use the right motor responses to form sounds correctly. They make errors because of the way they use the speech mechanisms—tongue, lips, teeth, mandible (jaw), and/or palate—to form the speech sounds. For others, the cause may be a physical or organic problem, such as a cleft palate, where an opening exists in the roof of the mouth, or a cleft lip, where the upper lip isn't connected, resulting in an inability to form some speech sounds.

A cleft lip or palate affects the ability to produce speech. Its incidence varies by race/ethnicity: about 1 of every 500 live births for Asian Americans, about 1 of 750 for Whites, and about 1 of 2,000 for African Americans (McWilliams & Witzel, 1998). The proportions of cleft lips and palates tend to be consistent; about 25 percent involve only the lip, 50 percent involve the lip and the palate, and the remaining 25 percent involve the palate alone. Most cleft lips can be repaired through plastic surgery and do not have a long-term effect on articulation. A cleft palate, however, can present continual problems because the opening of the palate (the roof of the mouth) allows excessive air and sound waves to flow through the nasal cavities. The result is a very nasal-sounding voice and difficulty in producing some speech sounds, such as s and z. A cleft palate is one physical cause of a speech impairment that requires the intensive work of many specialists. Plastic surgeons, orthodontists, and SLPs often join forces to help individuals overcome the speech disability that results from cleft lips and palates.

Although professionals can describe stuttering, they are unable to pinpoint or agree on a single cause for the problem (Ratner, 2005). Experts do believe, however, that stuttering episodes are related to stress, particularly when the conversational situation is very complex or unpredictable (Hall, Oyer, & Haas, 2001). Dysfluencies are more likely to occur and reoccur when the situation is challenging or confusing.

Voice problems, which are less common in schoolchildren, can be symptomatic of a medical problem. For example, conditions that interfere with muscular activity, such as juvenile arthritis, can result in a vocal disturbance. Voice problems also can be caused by the way the voice is used: Undue abuse of the voice by screaming, shouting, and straining can damage the vocal folds and result in a voice disorder. Rock singers frequently strain their voices so much that they develop nodules (calluses) on the vocal folds, become chronically hoarse, and must stop singing or have the nodules removed surgically. Teachers who notice changes in children's voices that are not associated with puberty should refer the student to an SLP.

Language impairments have many causes. Brain injury can result in conditions such as aphasia, which interferes with language production. Genetic causes are implicated when members of both the immediate family and the extended family exhibit language impairments (Owens, Metz, & Haas, 2003). The environment, especially the lack of experiences that stimulate language development, is also a major factor contributing to language impairments.

Clearly, then, heredity does not explain all language impairments. The quality and quantity of early language input has a definite effect on vocabulary development and language development (Harwood, Warren, & Yoder, 2002). Inability to benefit from language models can also contribute to inefficient or delayed language acquisition. For example, chronic otitis media, or middle ear infection, can cause children to miss hearing and imitating others' language during key developmental periods and may result in difficulties with language development (Roberts & Zeisel, 2002). Poor language development can be caused by environmental factors, including lack of stimulation and of the proper experiences for cognitive development and learning language. Some children do not develop language because they have no appropriate role models. Some are left alone too often; others are not spoken to frequently. Some are punished for speaking or are ignored when they try to communicate. Many of these children have no reason to speak; they have nothing to talk about and few experiences to share. Such youngsters are definitely at risk for developing significant language impairments.

Prevention

Many measures can be taken to prevent speech or language impairments. Many preventive measures have a medical basis and are implemented prior to the birth of a baby. Far example, polio and rubella can have devastating effects an an unborn baby; proper immunization protects adults and children from these and other diseases. A nutritional supplement of folic acid during pregnancy can reduce the risk of cleft palates and lips by 25 to 50 percent (Maugh, 1995). Proper prenatal care is important to the health of babies. Good nutrition influences the strength and early development of very young children.

The link between poverty and disabilities is clear (CDF, 2004). Those who are poor are less likely to have access to information and medical programs, which puts them at risk for diseases that result in disabilities (Utley & Obiakor, 2001). The availability of proper medical care before and after birth is crucial. Access to health care during childhood is important so that diseases in early childhood, such as measles and otitis media, can be avoided or treated early. Better public education programs available to the entire population inform people of the necessity of good prenatal care, nutrition, and medical care. Innovative approaches to the dissemination of information about the importance of protecting children from disease can make real differences in reducing the numbers of individuals who have language problems because they did not receive immunizations or early treatment for illness. For example, TV or radio advertisements may reach some families; different approaches might be more effective when informing other families. Health fairs sponsored by churches, sororities, fraternities, and other community organizations may prove to be more effective than traditional means in communicating important information to the African American community (CDF, 2004).

Overcoming Challenges

Nat all disabilities and conditions are permanent. In many cases therapy, effective instruction, and lots of hard work can restore effective speech or language functioning (ASHA, 2002). In others, strategic actions can help individuals compensate for the problems presented by disabilities. What is critical to facilitate outstanding results is intervention provided early enough to reduce or prevent the residual problems created by the disability or condition.

In addition to therapy and instruction, many individuals with speech or language impairments benefit greatly from technology, and the range of applications is considerable. Some applications correct speech mechanisms that are faulty or damaged. For example, an obturator forms a closure between the oral and nasal cavities when the soft palate is missing or has been damaged by a congenital cleft. An artificial larynx can be implanted in cases where the vocal folds have became paralyzed or have been removed because of a disease. This and other applications of medicine and technology can help many individuals with speech or language impairments communicate mare effectively so they can participate fully at school and in the community.