Sigmatism (lisping) is a distorted pronunciation of whistling, as well as hissing sounds. The disorder is typical for mechanical and functional dyslalia, various forms of dysarthria, open rhinolalia. With sigmatism, interdental, near-tooth, labio-dental, lateral, nasal pronunciation of phonemes can take place. The defect of sound pronunciation and its form is diagnosed as part of the examination of oral speech. The main areas of corrective speech therapy intervention include the preparation of the articulatory apparatus, the development of phonation breathing, sound production, automation of the skill of correct sound pronunciation.
Sigmatism is the shortcomings of the pronunciation of hissing ([Ж], [Ш], [Ч], [Ш]) and whistling ([С-С ′], [З-З ′], [Ц]) phonemes. Both groups belong to the sounds of late ontogeny, while hissing sounds are considered to be articulatory more complex than whistling sounds. Among the defects in the sound design of speech, various variants of sigmatism are more common than other distortions. In older preschoolers with dyslalia, wheezing sigmatism is detected in 22% of cases, hissing sigmatism - in 24%, in children with erased dysarthria - in 95% and 82%, respectively. Often, defective sound pronunciation persists in adults.
Causes of sigmatism
Sigmatism as a short-term phenomenon can occur in children during the period of physiological change of teeth. When milk teeth fall out, the tip of the tongue sometimes occupies an interdental position, which gives speech a lisping tone. Usually, children quickly find compensatory articulation that promotes normal pronunciation, and the problem soon disappears. Persistent pathological sigmatism has the following causes:
- Dental anomalies. Prognathia can lead to labio-tooth sigmatism. The cause of interdental pronunciation of sounds is usually an anterior open bite, a narrow and high hard palate, and a shortened frenulum of the tongue. Nasal pronunciation is typical of palatine clefts.
- Violation of the innervation of the organs of articulation. It leads to a change in the tone of the tongue, lethargy of the soft palate, paresis or increased spasticity of the lips. With innervation inferiority, interdental or lateral sigmatism most often occurs.
- Diseases of the ENT organs. Difficulty in nasal breathing caused by adenoids, vasomotor or allergic rhinitis, contributes to the fact that the child's mouth constantly remains parted. In this case, the tip of the tongue is in the interdental position - interdental sigmatism is formed.
- Incorrect articulation patterns. There is no organic pathology from the articulatory organs. The lack of formation of articulatory praxis comes to the fore. This situation can occur in somatically weakened children, when imitating incorrect speech patterns.
- Hearing loss. A decrease in physical hearing usually leads to sound substitutions - parasigmatism, less often with hearing loss, distorted pronunciation of sounds is observed. It is due to fuzzy auditory differentiation of correctly and defectively pronounced phonemes.
In practical speech therapy, sigmatism occurs in a number of speech disorders: various forms of dyslalia and dysarthria, alalia, rhinolalia, ONR, FFN. Lisping pronunciation may be noted in children with intellectual disabilities.
Phonetic characteristics of whistling and hissing
Whistling [С], [З] and hissing [Ш], [Ж], [Ш] - consonants, oral, anterior lingual, fricative. Of these, [З] and [Ж] are voiced (during phonation, the vocal folds vibrate, making a voice), the rest are deaf. Whistling [C] and hissing [Ch] differ only in the way they are formed - they are occlusive-slotted. [H] and [Sh] are always soft, [Ts], [W], [L] are always hard, [S], [Z] have soft pairs [S ′] and [Z ′]. An important difference between the whistling and hissing group is the basic articulation pattern, which includes:
- position of the lips: when pronouncing whistling lips, they are stretched in a smile, when pronouncing hissing lips, they are rounded and slightly extended forward;
- the position and shape of the tongue: when articulating whistling tongues, the tongue is located in a “hill” behind the lower incisors, while articulating hissing ones, it is near the alveoli in the form of a “cup”;
- characteristics of the air jet: in whistlers it is narrow, cold; in hissing ones it is wide and warm.
Types of sigmatism
All forms of sigmatism are divided into two large groups: hissing sigmatism and whistling sigmatism. Methods for correcting defective sound pronunciation depend on the nature of the distortion of sounds. The main types of sigmatism in both groups of sounds are identical:
- Interdental. The tip of the tongue takes a position between the upper and lower incisors. Phonemes acquire a lisping sound.
- Tooth. The tongue rests against the edges of the incisors, blocking the passage of air through the interdental gap. The sound produced is acoustically close to [T].
- Labio-tooth. The lower lip approaches the upper teeth, the air comes out jerkily. Instead of the correct sound, a distorted [F] or [V] is heard.
- Side. The exhaled air stream exits through a one-sided gap or along both lateral edges of the tongue. The sound is noisy, squelching.
- Nasal. During phonation, air does not exit through the mouth, but through the nasal cavity. Because of this, the sound gets a snoring overtone with a nasal tint.
In addition, hissing [Ш], [Ж] may have other types of distortion that are characteristic only for them:
- lower - the tongue is lowered behind the lower incisors, hissing sounds are pronounced softly;
- buccal - the air stream goes into the cheeks, causing them to swell, instead of sound, noise is heard;
- posterior lingual - air passes between the hard palate and the back of the back of the tongue, a "huff" or "whoop" is heard, reminiscent of a southern Russian dialect.
Diagnostics
To identify sigmatism, determine its form and causes, a speech therapy examination is carried out. It is also important to understand what kind of speech disorder is sound distortion. During the diagnosis, the speech therapist examines the medical and speech history, then proceeds to an objective examination:
- articulatory organs. The organs of the oral cavity are examined, the tone of the facial and articulatory muscles, the state of oral praxis are assessed. When anomalies of the maxillofacial area, violations of muscle tone are detected, a preliminary speech diagnosis is established. If necessary, a referral is given for a consultation with an orthodontist, a neurologist.
- Speech hearing. The differentiation of sounds is checked when they are pronounced in isolation, in syllables, words, phrases. For this, special picture and speech material is used, corresponding to the age and intellect of the speech pathologist. Special didactic techniques are used to distinguish between different types of sigmatism and parasigmatism.
- Sound states. It is carried out to identify all defects in sound pronunciation (both phonetic and phonemic), the number of disturbed sounds. With defects of hissing and whistling, the type of sigmatism is established. After that, the sequence of corrective work is determined.
If a child is expected to have a systemic speech disorder, an examination of the lexical and grammatical aspects of speech is mandatory. If hearing loss is suspected, it is advisable to refer the subject to an otolaryngologist to check the state of auditory function.
Exercise "Cup" - basic for setting hissing sounds
Correction
Health care
Special treatment is required to eliminate factors predisposing to sigmatism. Bite correction may include various types of orthodontic care: wearing braces, special mouth guards, devices of various effects. If necessary, orthognathic intervention is performed. The choice in favor of surgical tactics with a shortened frenulum is made if it is impossible to stretch the ligament using speech therapy methods.
In case of violations of the innervation of the articulatory muscles, all speech therapy work is carried out against the background of drug treatment, physiotherapy, prescribed by a neurologist. The absence of free nasal breathing, as the cause of sigmatism, requires appropriate treatment: removal of adenoids, antiallergic therapy.
Logopedic correction
Speech therapy work to eliminate all forms of sigmatism is subject to a single algorithm. It includes three periods during which certain corrective tasks are solved:
- Preparatory. At this stage, the necessary articulation structures are formed: the correct position of the lips, tongue. Work is underway to develop the strength and direction of the air jet. Reference sounds are practiced ([I], [F] - for [S], [T], [S] - for [Sh]. The methods by which the tasks are achieved include articulation and breathing exercises, and, according to indications, speech therapy massage .
- Sound production. It is carried out in different ways: by imitation (“how a pump whistles”, “how a mosquito rings”, “how a snake hisses”), using articulation exercises or using tools (probe substitutes, probes). The base sound for staging all whistling is [S], for other hissing - [Ш].
- Automation. Having achieved the correct pronunciation of an isolated sound, they proceed to fixing it, sequentially introducing into syllables (direct, reverse, with a combination of consonants), words, phrases and spontaneous speech. After working out hard sounds, they begin to assimilate their soft pairs. The stage of differentiation for sigmatism and other sound distortions is not provided.
The traditional sequence of staging sounds is determined by the timing of their appearance in ontogeny. If both groups are violated, the whistling sound is first performed, then the hissing (an exception may be dysarthria, when the sounds are put in the reverse order).
If sigmatism is part of a complex speech defect, then work is carried out in parallel on other aspects of speech: syllabic structure, vocabulary, grammar, prosody, etc. The terms for correcting sigmatism may vary for different children, the period of speech therapy work takes up to 45-9 days or more.