Most people tend to believe that a lisp is a speech condition where a person’s “s” and “z” tend to be substituted in their speech, resulting in distorted conversation.
However, while this is true to a certain extent, lisping impediments are much more complicated than most people think. Speech therapists, doctors and other specialists have identified four major forms of lisp speech disorders.
Primarily, speech, or any sound for that matter, is produced with the combination of the correct placement of the tongue in the mouth and the expulsion of air. With a frontal lisp, the tip of the tongue protrudes between the front teeth, that is, it obstructs the airflow. Consequently, the “s” and the “z” sounds in words tend to be vocalized as “th” sounds. For example, words like “pass” and “sleep” maybe pronounced as “path” and “theep”. This is the most commonly found type of lisp.
As the name suggests, this lisp has an association with the soft palate, that is, the roof of the mouth. Whenever an individual rolls their tongue too far back and touches it against the roof of the mouth, they tend to develop palatal lisping.
This is a lot like a frontal lisp. The main difference is that in a frontal lisp, the individual protrudes their tongue between the front teeth, while with a dental lisp, the individual pushes their tongue against the front teeth. Just like a frontal lisp, a dental lisp may be seen in very young children as they are just learning to form coherent sentences, but it usually goes away by the age of four.
Lateral LispA lateral lisp occurs when the airstream for the ‘s’ sound, that is normally directed through the centre of the mouth, is thrust down laterally around the sides of the tongue. So instead of a hissing, the sound is more of a slushy noise where the sound swirls out of the sides of the mouth rather than directly through the centre. Unlike dental lisps and frontal lisps, lateral lisps are not a part of normal speech development.
What Causes Lisp Speech Disorders In People?
There are many things that give rise to lisps in individuals, and most of these happen at a very early age. Most lisps are caused by wrong tongue placements in the mouth, which in turn obstructs air flow from the inside of the mouth, causing the distortion of words and syllables.
Tongue-ties are also considered a probable cause of lisping. Yet so far, it is unknown as to whether it is caused by the tongue itself or the muscles that control the movements of the tongue inside the mouth. However, in most of the cases involving growing children who are just learning to speak coherently, lisping is just temporary and tends to go away after a certain age.