Lisp

A lisp is a speech disorder under the category of articulation disorders which is characterised by difficulty pronouncing certain sounds, particularly the "s" and "z" sounds. It often involves incorrect tongue placement, teeth alignment, or airflow during speech production, resulting in distorted or substituted sounds. Lisps are common speech disorders and can be effectively treated with appropriate intervention and support from a qualified speech-language pathologist^[1].

There are a few different types of lisps:

1. Interdental Lisp: In an interdental lisp, the tongue protrudes between the front teeth during speech, causing an airflow disruption. This can result in a "th" sound instead of the intended "s" or "z" sound. For example, "sun" may sound like "thun"^[2].

2. Lateral Lisp: In a lateral lisp, air escapes over the sides of the tongue during speech instead of flowing over the center of the tongue. This produces a "slushy" or "wet" sound, often heard on "s" and "z" sounds. For example, "sun" may sound like "shun" or "thun"^[3].

3. Palatal Lisp: In a palatal lisp, the middle of the tongue touches or comes close to the hard palate, the roof of the mouth, during speech. This leads to a muffled or "swishy" sound on "s" and "z" sounds. For example, "sun" may sound like "shun" or "zhun"^[4].

The causes of lisps can vary and may include:

1. Oral Structure and Coordination: Some individuals may have structural differences or difficulties with tongue, teeth, or jaw coordination, affecting their ability to produce certain sounds correctly^[5].

2. Speech and Language Development: Lisps can arise during the process of speech and language development. If a child does not acquire the correct articulatory patterns for producing "s" and "z" sounds, a lisp may develop^[6].

3. Muscle Weakness or Poor Motor Control: Weak or underdeveloped oral muscles, as well as difficulties with motor control, can contribute to lisps^[7].

4. Dental or Orthodontic Factors: Dental issues, such as misaligned teeth or an overbite, can impact speech production and contribute to lisps^[8].

Lisps can vary in severity and persistence. Some individuals may outgrow a lisp as their speech and articulatory skills develop, while others may require intervention from a speech-language pathologist to improve their speech production and overcome the lisp^[9].

Speech-language pathologists can assess and provide targeted therapy to address the underlying causes of a lisp. Therapy may involve exercises to improve tongue and muscle coordination, practice with correct sound production, and strategies to promote proper placement of the tongue, teeth, and lips during speech^[10].