Phonological Disorder Health Article

Definition

Phonological disorder occurs when a child does not develop the ability to produce some or all sounds necessary for speech that are normally used at his or her age.

Description

Phonological disorder is sometimes referred to as articulation disorder, developmental articulation disorder, or speech sound production disorder. If there is no known cause, it is sometimes called "developmental phonological disorder." If the cause is known to be of neurological origin, the names "dysarthria" or "dyspraxia" are often used. Phonological disorder is characterized by a child's inability to create speech at a level expected of his or her age group because of an inability to form the necessary sounds.

There are many different levels of severity of phonological disorder. These range from speech that is completely incomprehensible, even to a child's immediate family members, to speech that can be understood by everyone but in which some sounds are slightly mispronounced. Treatment for phonological disorder is important not only for the child's development to be able to form speech sounds, but for other reasons, as well. Children who have problems creating speech sounds may have academic problems in subject areas such as spelling or reading. Also, children who sound different than their peers may find themselves frustrated and ridiculed, and may become less willing to participate in play or classroom activities.

Causes

Phonological disorder is often divided into three categories, based on the cause of the disorder. One cause is structural problems, or abnormalities in the areas necessary for speech sound production, such as the tongue or the roof of the mouth. These abnormalities make it difficult for children to produce certain sounds, and in some cases make it impossible for a child to produce the sounds at all. The structural problem causing the phonological disorder generally needs to be treated before the child goes into language therapy. This therapy is especially useful, because, in many of these cases, correction of the structural problem results in correction of the speech sound problem.

The second category of phonological disorder is problems caused by neurological problems or abnormalities. This category includes problems with the muscles of the mouth that do not allow the child sufficient fine motor control over the muscles to produce all speech sounds. The third category of phonological disorder is phonological disorder of an unknown cause. This is sometimes called "developmental phonological disorder." Although the cause is not known, there is much speculation. Possible causes include slight brain abnormalities, causes rooted in the child's environment, and immature development of the neurological system. As of 2002, there is research pointing to all of these factors, but no definitive cause has been found.

Symptoms

The symptoms of phonological disorder differ significantly depending on the age of the child. It is often difficult to detect this disorder, as the child with phonological disorder develops speech sounds more slowly than his or her peers; generally, however, he or she develops them in the same sequence. Therefore, speech that may be normal for a four-year-old child may be a sign of phonological disorder in a six-year-old.

Nearly all children develop speech sounds in the same sequence. The consonant sounds are grouped into three main groups of eight sounds each: the early eight, the middle eight, and the late eight. The early eight include consonant sounds such as "m," "b,", and "p." The middle eight include sounds such as "t," "g", and "chi," and the late eight include more complicated sounds such as "sh," "th," "z," and "zh." Many children do not normally finish mastering the late eight until they are seven or eight years old. As children normally develop speech sound skills, there are some very common mistakes that are made. These include the omission of sounds, (i.e., frequently at the end of words), the distortion of sounds, or the substitution of one sound for another. Often the substitution is of a sound that the child can more easily produce for one that he or she cannot.