I have a client with a frontal lisp. He has already made significant improvement during therapy for /sh/, /j/, /ch/. The only sound left is /s/ and he can retract the tongue to produce an "okay" /s/ - it's missing that crispness. He's been through lots
This is a fun question to answer, because it comes on the tail of a rather lengthy discussion between Dr. Stephanie Tarrant Martin and myself about a similar question. My friend, Dr. Martin, who is dually certified in both Audiology and Speech Language Pathology would first ask you about the child's hearing. A simple hearing screening at 20dB is not sufficient to answer this question. Dr. Martin, continually admonishes us, there is no such thing as a "mild" hearing loss in children. This is because a hearing loss as small as 16dB is educationally significant and could explain this child's difficulty in producing the /s/ sound, particularly if the loss is in the higher frequencies. So, first get an accurate measure of the child's hearing threshold for the frequencies 250, 500, 1000, 2000, 3000, 4000, 6000 and 8000 Hz.
This will tell you about the child's hearing acuity, but not the child's discrimination skills. The second question Dr. Martin would ask you is, "Is this a production or a perception error?" That is, can the child hear the difference between a "crisp" /s/ and the soft or "slushy" /s/ you are describing? Offer the child several opportunities to discriminate between a "crisp" and a "soft" /s/ when listening to your speech. Be sure to sample discrimination in single words and in sentences.
If the child cannot make the discrimination, then this is where to start training. You may need to begin using very slushy /s/ sounds, contrasted with very crisp /s/ sounds. Once this is mastered, progress to less slushy /s/ sounds. You may also want to use some devices to assist the child's listening. A simple amplification system such as you might use during the auditory bombardment phase of phono therapy would be useful in boosting the loudness of the /s/ sound and aid in teaching. Assuming the child's hearing is WNL, you're not done teaching discrimination, until the child can hear the difference without assistive listening devices.
Once the child has perception you can begin production training. How did you go about teaching the other sibilant sounds? Specifically, where is the tongue placement? Are there structural issues influencing tongue placement? Children with chronic allergies, small pharyngeal structures or other constrictions in the oral and respiratory cavities sometimes develop an open mouth posture and/or a forward tongue carriage. This posturing is used to facilitate breathing, and no amount of scolding or nagging will "teach" the child to hold her mouth closed if the respiratory passage is compromised. At this point, a medical referral is warranted. Sometimes, children retain the open mouth posturing AFTER medical issues have resolved. In this case the posture is habitual and not functional, and the child can be reminded to close her mouth at rest.
You mentioned having used oral-motor therapy. Children with a history of open mouth posturing often have low muscle tone in the mandible and tongue. The child may have low tone for other, neurological reasons, as well. Low tone, for what ever reason, will diminish the child's ability to narrow and harden the tongue for crisp sibilant sounds. Blowing harder over a flaccid tongue does not produce a crisp sound, but rather exaggerates the slushy sound.
Sibilant sounds may be produced with the tongue tip up or down. Most people use a tongue up position, but many people can make reasonable sounding sibilants with the tongue tip down. So when we can't teach tongue elevation for sibilants we often teach the tongue down position. My experience warns against this in people with multiple errors. Speech is the best exercise for tongue strengthening. The tongue is not strengthened in a tongue down position. Although most sounds can be taught with this position, when teaching children with multiple errors, I always seem to come up against one sound that cannot. The child and I then have to change to a tongue up position. Thus, the child makes most sounds tongue down and suddenly, I change the rules and ask for the tongue up. I've found it more advantageous to stick with the tongue up position in cases where there were multiple sibilant errors.
So far we've addressed production vs. perception and tongue placement. I'd like to focus now on your teaching. The "dg, ch, sh and s" sounds are similar in that a narrow band of air is passed over a fairly stiff and elevated tongue. The sounds are differentiated by lip positioning, voicing, affrication, etc. but they are similar in tongue position. So I ask, "Exactly what makes the child's production an error?" If it is tongue position then you must focus your teaching on tongue position. If it is blowing too hard or too soft, then you must focus your teaching on blowing. If it is pressing the tongue to the palate too tightly, then focus your teaching on light contact. Study the child's error and contrast that with correct production until you can describe the error in short simple words. You need to use these words in your teaching. Regardless of how you establish correct tongue placement, the child needs a set of instructions she can memorize and say to herself when practicing. These words should be the opposite of the error. Thus, if the error is pressing the tongue to the palate too vigorously, then the instructions need to be, "Light touch." These words need to be used in three places in your teaching: in the directions, in the praise, and in the error corrections. If the error is that she uses a soft mushy tongue that is tipped down, the directions need to be "Make your tongue hard. Make your tongue flat. Put it up to your teeth." Praise, too, needs to reflect these words. During this stage of learning praise such as, "good job," is hollow and has little teaching value. Praise such as, "good /s/," is not much better. Praise such as, "Great! I saw your tongue go up!" or "That was a hard, flat tongue!!" will tell the child exactly what she did well. She will be far better able to repeat her success when she knows exactly what made her successful. Lastly, these words need to appear in the error correction. Ignoring errors has limited value and being told, "Nope, that was wrong," hurts your feelings. Being told, "Your tongue was down, put it up," gives you the necessary feedback to make a correction.
A second point about teaching is to teach the child to monitor and discriminate her own productions. An assistive listening device might come in useful for this. The auditory trainer described earlier will amplify the child's sound for her. Simple listening tubes (a length of plastic tubing) held from the child's mouth to her ear will also help her hear this sound. I've had luck fitting a small funnel to the end of the tube near the mouth to "catch" the sound. Encourage the child to listen to and evaluate her own speech. If the child can hear the error, she can then give herself the directions to correct it. Self correction is not mastered until it can be done without the assistive listening device.
The two skills I have found most critical to generalization are the ability to verbally mediate the production and the ability to self correct. Verbal mediation, that is, the ability to tell yourself the directions allows you to practice when the teacher is not present. Similarly, the ability to identify errors and replace them with correct productions also increases the likelihood the sound will be used when the teacher is not present. If these same teaching strategies are employed when teaching multiple sounds, especially sounds containing the same placement error, it is quite likely the verbal mediation and self-correction will extend or generalize from one sound to the next.
In summary, be certain of hearing acuity, particularly in the higher frequencies. Next determine if it is a production or a perception error. Teach the child to discriminate the correct production in your speech. When the child has multiple errors on sibilants, select a tongue position that will address the error in all the error sounds. Study the child's error productions and develop a set of short simple directions the child can use to verbally mediate her own speech. Provide specific reinforcement. It is not good enough to say, "good job," you must tell her what the job was, and what was so good about it. Teach the child to self-monitor and reward her for self-corrections. Use these strategies when you move from one sound to the next to facilitate generalization of the teaching aids as well as the sound patterns.
Yes, but what if... If the child does not have adequate hearing, consult someone trained in teaching speech to children with hearing impairment. If the child's oral motor problems are part of some other issue such as cerebral palsy or multiple sclerosis then you must consider the adequacy of the mechanism to ever produce a "crisp" /s/ sound. Perhaps your standards are un-realistic given the child's physical mechanism. Similarly, if the child's cognitive abilities preclude verbal mediation, self correction or match-to-sample (for discrimination), the appropriateness of your goals must be re-considered.
Thank you for this opportunity to consider this question. I enjoyed the opportunity to reflect on this teaching issue, and hope my reflections may be of use to you.
Dr. Cheryl B. Gerard is a professor at Minot State University where she has taught, supervised clinical practica, and engaged in research relating to many areas of speech, language and communication. Dr. Gerard has over 25 years of experience serving a variety of persons with communication disorders across diverse settings including public schools, specialty clinics, institutions, and assisted living centers.