Category Archives for "Speech Clarity – Speech Development & Difficulties"

What is Speech Intelligibility?

What is Speech Intelligibility

speech intelligibility

Intelligibility of speech is the percentage of speech that a listener can understand. If you can only understand half of what a child is saying then their speech intelligibility rating would be 50%.

​Speech Intelligibility changes with a child’s age. Speech development begins with babbling and then speech matures until older children can say all the sounds in their primary language/s and everyone can understand them.

​Speech Intelligibility is Expected to Improve with a Child’s Age

Younger children are expected to be harder to understand then older children. Speech Sound Developmental Checklists and Speech sound charts can help parents, teachers and carers to see if the level of speech intelligibility is at expected levels for a child’s age.

​The graph below shows that an 18 month old child will have lower speech intelligibility levels than a 3 year old child. This does not mean that a 3 year old will not still make some speech sound errors. It means that they are only using a few speech sound errors and that most people will be able to understand what they are saying. Lynch, Brookshire & Fox (1980), p. 102, cited in Bowen (1998)

​Why does Speech Intelligibility Change with Speech Developmental Stages?

speech intelligibility
There are 3 main areas to consider when looking at speech intelligibility
1 Articulation
Toddlers do not have the fine motor control of their tongues and lips to be able to say all the sounds correctly and so their speech is characterised by speech sound developmental errors.

​These are called articulation errors. For example, sounds like the “r” sound can be difficult for toddlers. The “r” sound requires a fine curling of the tongue and young children often will substitute the “r” sound for an easier sound (e.g., w). You will often hear a 2 year old say “wed” for “red”.

2 Motor speech co-ordination 

​Young children also cannot move their tongue and lips fast enough to keep their speech clear as they try to say longer words and sentences. This is called motor speech co-ordination. It is a bit like doing buttons up. Young children may be able to do easy buttons but might take a long time. As their fine motor co-ordination increase their ability to dress becomes easier and faster.

3 Phonological Processes
​Toddlers use more phonological processes that reduces speech intelligibly than older children. As toddlers do not have the oral motor skills to say words 100% correctly, they use speech sound patterns that simplify words.

​One example of a phonological process is called “cluster reductions”. Speech sound clusters like “sp, sk, dr, bl” are very difficult for young children to say. Most young children reduce the cluster to one sound (e.g., “dep” for “step”, “back” for “black”). Young children use lots of phonological processes reducing speech intelligibility. As children get older they use less and less and so speech intelligibility improves.

​As speech develops children use less articulation errors, their rate & co-ordination of speech improves and they use less phonological errors.

​See the Speech Sound Developmental Checklist to see the ages speech sounds and phonological processes are typically present.

​Speech Intelligibility as a measure of Severity of Speech Delays and Speech Disorders.

speech intelligibility

Children with speech delays and speech disorders will often have lower speech intelligibility percentages than same age children.

​If a 3 year old child has speech delays they may be still making speech sound errors like a 2 year old would be making. This can reduce their speech intelligibility for their age.

​Speech disorders such as dyspraxia of speech (CAS) is characterised by significant reductions in speech intelligibility. Speech intelligibility may be one of the criteria used to determine how functional a child’s speech is in their community. If most people they interact with them cannot understand them, then it would be considered a significant speech impairment.

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What is a Speech Disorder?

What is a Speech Disorder?

speech disorder

A speech disorder is different to a speech delay. A speech disorder is more than a child just using immature speech patterns. Speech disorder means that their speech is following a non-typical speech development path.

​Some journals and medical practitioners do use the term “speech disorders” as an umbrella term to mean all speech impairments. Consequently, in the literature you will find terms like speech delay, speech disorder, speech sound disorder (SSD), speech impediments, speech impairment, speech difficulties, phonological disorder, phonological delay, articulation disorder and speech dyspraxia (CAS) used inter-changeably.

​What are the characteristics of a speech disorder?

Children with a speech disorder often are more difficult to understand than a child with a speech delay. It can also be harder and take longer for therapy to improve speech development than for a child with a speech delay.

Speech impediments or problems may be identified even during baby speech development and even when baby babble does not develop well. In the early stages of speech problems, it can be hard to determine if it is a speech delay or a speech disorder.

​Typical Toddler speech development is characterised by learning how to say sounds in a predicable order and the use of different phonological processes at different ages. Toddlers with a speech disorder may not follow these predictable paths.

​Types of Speech Disorders.

speech disorders in children

There are many different types of speech disorders however the main ones include:

Phonological Disorders

These are speech disorders characterised by children using non-developmental or non-typical speech sound patterns (phonological processes) that simplify how children say words. Common non-developmental phonological processes that indicate a child may be at risk of a speech disorder includes:

  • Word-initial deletions – e.g., “dad” is said as “_ad”
  • Vowel distortions – e.g., “pen” is said as “pun”
  • Sound preference substitutions – e.g., there is over use of one particular sound e.g. /d/ is used in many words such as “ball” said as “dall”, “car” said as ‘dar”, peanut butter said as “deedut duder”

Motor Speech Disorders

These are speech disorders characterised by poor co-ordination of the child’s tongue, lips, breathing and thinking. Child Apraxia of Speech (CAS) is one example of a motor speech disorder. CAS is also known as Childhood Verbal Dyspraxia or Speech Dyspraxia, or Developmental Dyspraxia.

​There is “nothing wrong” with the child’s tongue or lips. They can usually move their tongues and lips just the same as other children when they are not thinking about it (e.g., licking lips to get food off ). However, when they try to consciously make these mouth movements to say words all the movements become very uncoordinated. Their “motor” control is poor. Some children will have mild motor speech disorders and other will have very severe motor speech disorders that can stop them being able to speak. Some children born with cerebral palsy or that have had head injuries may have Dyspraxia of speech. However CAS refers to children that have verbal dyspraxia but there are no obvious causes of these problems.

What to do if you think your child might have a speech disorder

speech disorder
  • Obtain a speech therapy assessment and global developmental check
Obtain a speech therapy assessment if you have concerns your child is not developing speech well or their clarity of speech is poor for their age. Only by completing specific assessment can a diagnosis of a speech disorder be made. It can also be important to eliminate factors such as ‘blocked ears” or other medical concerns

​As some children present with speech delays AND speech disorders at the same time, it is not always a clear cut diagnosis. Late talkers and children with autism who are not using any words or only attempting a few words may be at risk of speech disorders. Work on developing more spoken words and language skills may be required before the speech difficulties can be tackled.

​It is important that the speech therapist is experienced in treating speech disorders so that the correct programme or programmes can be implemented as soon as possible. Contact SpeechNet Speech Therapy if you have any questions.

  • Provide a rich speech and language environment in the home / child care centre or school.
SpeechNet Speech Pathology website provides a huge range of parent suggestions on how to provide a rich speech and language environment for all children. These techniques and ideas are of particular importance to children showing speech impediments such as speech disorders.

The everyday moment videos particularly demonstrate how you can be modelling and supporting language in simple everyday interactions. The book reading and toy printables provide ideas of how to encourage speech and language while enjoying books or playing! Children with speech disorders need lot and lots and lots of help. Just doing speech therapy once a week is generally not enough. It is important that every interaction is a fun way to support speech development in children.

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What is a lisp?

What is a lisp?


A Lisp is a term people use when the /s/ and /z/ sounds are said incorrectly. Other related sounds like “ch” & “sh” may also be affected.

​Part of the child speech development process involves children learning where to put their tongues and lips in order to make all the different sounds in a language. A lisp is when children do not quite get the tongue and lips in the correct place while they are learning to say the /s/ and /z/ sounds. Sometimes this incorrect placement becomes a “habit”. This is why some older children and even adults continue to “lisp”.

​Types of Lisps

There are a few different kinds of lisps. Some would be considered part of “typical speech development” in children and some would be considered a speech impediment.

Types of Lisps


Interdental lisps

This is probably the most common type of lisp.In an interdental lisp is sometimes called a fronal lisp. This is because the tongue comes too forward as the child says the sound. The tongue protrudes between the front teeth and the air-flow is directed forwards. The tongue and teeth positions are the same as when we say the “th” sound. So “sock” sounds more like “thock” and “buzz” sounds more like “buth”.

​Children developing speech along typical paths may have interdental lisps until they are about 4½ - after which they disappear without any help or therapy. If they don't 'disappear' an SLP/SLT assessment is indicated.

​Sometimes the tongue does not go between the teeth but pushes against the teeth. This makes the s “muffled” rather than a full “th” sound.

​Possible causes of an Interdental Lisp:

The “cause” of an inter-dental lisp can just be incorrect placement of the tongue due to a maturing speech system.

​Sometimes a lisp occurs because there is an underlying “tongue thrust” swallow.

​This means the forward tongue position is not only happening as the child is saying the /s/ and /z/ sounds it is happening every time they swallow. This can have an impact on the alignment of their teeth. This is why an assessment by a speech pathologist may required earlier than 4 years.

​Some children produce many sounds interdentally. Tongue protrusion, or very 'forward' tongue placement may be occurring when the child says not only /s/, /z/, 'sh', 'zh', 'ch' and 'j', but also /n/, /l/ , /d, /d/and other sounds. This is not considered typical development and would be suggestive a speech disorder.

​In some children 'everything' seems interdental. This may sometimes be an indication that the nose is constantly obstructed, due for instance, to allergy, infection, large adenoids or craniofacial anomalies, or may be associated with habitual mouth breathing, tongue thrust, or sucking habits.

Lateral lisp

A lateral lisp is where the middle of the tongue hits the palate instead of the tongue tip touching just behind the teeth when the /s/ and /z/ sounds are pronounced. This tongue placement can make the airflow go to the sides of the mouth rather than straight forward. This is not considered part of typical speech development and hence is considered a speech disorder.

Do I need to worry if my child has a lisp?


This completely depends on the age of the child and the type of the lisp.

​Some children seem to be able to say the /s/ sound perfectly well from 2 years of age.It is however a perfectly normal developmental phase for some (not all) children to produce the interdental lisp on a /s/ and a /z/. This means the child places their tongue on the or between the teeth as they say the /s/ and /z/ sounds until they are about 4½ years of age.

​On the other hand, lateral lips are part of the typical child speech developmental. The speech of a child with a lateral lisp should be assessed an experience speech pathologist. A speech pathologist that also has experience with tongue thrust swallows may also be warranted. Even young children that start to say the /s/ sound with a later lisp should seek advice from a speech therapist.

​Does a lisp impact on the clarity of a child’s speech?

A lisp can reduce clarity to a certain extent depending on how prominent the lisp is. If the lateral /s/ strongly produced words like “mouth-mouse” and “think-sink” may be confused.

​A lateral lisp can make a child’s speech seem very unclear and even spit can gather in the corners of the mouth as the lateral airflow pushes saliva to the side. This can not only reduce speech clarity but also may have self-concept issues later on.

​Some children grow up in an environment where their lisp are not noticed or not considered an issue. Sometimes adults reinforce the interdental lisp by considering it is “cute”..

​Unfortunately, though some children are brutally honest and will point out that the child with the lisp “sounds funny”. They may face ridicule or teasing can be likened to the many “comedy characters that are portrayed with a lisp (e.g., daffy duck!).

​Should I get a speech therapy assessment for my child’s lisp or wait?


Waiting well past 4½ is not advised. The longer the child waits to seek tongue position correction, the stronger the old 'habit' will be. Some younger children may not have the ability to attend or make changes to the lisp however this can be determined with a speech therapy assessment. Sometimes high school students become more aware of their lisps as peer interactions increase in importance. If an older child is motivated to correct the lisp – it is quite possible it can be achieved with the right programme.

​If the child is presenting with a tongue thrust swallow or a lateral lisp early intervention is advised.

Contact SpeechNet Speech Pathology if you have any concerns about your child’s speech.

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Speech Impediment: What are Speech Impediments in Children

Speech Impediment: What are Speech Impediments in Children?

speech impediment

Speech Impediment is a broad term used to describe the huge range of different types of speech and verbal communication problems children may present with. The term speech impediment can sometimes be used when the underlying cause of speech issues are not easily determined or there is more than one underlying speech issue (e.g., delayed and disordered speech). Terms like speech difficulties, child speech problems, speech disorders are all used instead of speech impediment at times.

​Types of Speech impediments in Children

Speech Impediments in children can refer to:

Structural Problems

Some children are born with abnormal tongue, lips or palates. If the facial structures are atypical it can impact on speech development. Children born with cleft lips and palates may have speech problems for example. Tongue-ties may also impact on speech development.

Nerve Damage

Children with cerebral palsy or those that have had some kind of brain damage (e.g., car accident or near drowning) may have damage to the nerves that help the muscles of the face and chest need for speaking. Speech impediments may result.

Hearing Problems

Children born with hearing problems and those with chronic ear infections can have speech delays and difficulties.

Developmental Difficulties

Children with slow to develop speech or other developmental problems may have speech sound developmental delays resulting in speech impediments. Intellectual impairment, autism and verbal dyspraxia can impact on how easily children learn to verbally speak.

Articulation difficulties

Difficulties physically saying sounds are sometime referred to as speech impediments. An example would be a lisp.


Sometimes children that stutter are referred to as having a speech impediment.

Implications of a Speech Impediment for a child

speech impediment

Implications of a speech impediment vary greatly depending on severity and cause of the speech difficulty. No matter what the cause however the literature clearly shows that child have the best outcomes when intervention is sought as early as possible.

​Early intervention should be sought if red flags for speech impediments are showing during baby speech development, toddler speech development or ongoing problems in preschool & school are present in regard to speech development.

There is evidence that young children with speech impediments are at risk of concerns in areas such as:

Social skills
  • To develop social skills children learn to talk to both adults and children. Unclear speech can impact on their ability to engage in “conversations” (either verbally or non-verbally). It is very hard to negotiate, compromise with others, and to be able to recognize and follow social “rule” with a speech impediment.
Expressive (using) language
  • Speech sound development and growth of sentences are very closely linked. Children with poor speech clarity tend to keep their sentences short so that others have more of a chance to understand them. Using language through speech, sign or alternative forms of communication to communicate wants, needs, thoughts and ideas may be needed if speech impediments are severe. Early grammar is also very closely linked to speech sound development. If a child can not say the /s/ sound it can impact on their ability to use plurals (e.g., “two CakeS”) or indicate ownership (e.g., Mummy’s bag).
Self Confidence
  • If children have tried to talk and have not been understood it can impact on their self-confidence. A child’s belief in their ability to perform a task.• Fluency or stuttering can be related to poor speech sound development. The smoothness or flow with which sounds, syllables, words and phrases are produced when talking can make it sound like a child has a stutter
  • The child may be “clingy” or always want a parent/carer to be around if they are their main means of communicating with other, If children need you to translate or help with their communication their independence skills can be impacted on by their speech impediments.
Fluency or Stuttering
  • Fluency or stuttering can be related to poor speech sound development. The smoothness or flow with which sounds, syllables, words and phrases are produced when talking can make it sound like a child has a stutter
  • A child may become overly frustrated due to not being understood. Hitting out, biting, screaming and throwing things can be more related to reduce clarity due to a speech impediment than poor behaviour alone.
Reading and Spelling
  • Reading and spelling which rely on sounding out the words can be impacted on by speech impediments. If you can’t say the right sounds when you are trying to spell a words it makes spelling that work even more difficult.

What to do if you suspect a child has a speech impediment.

speech impediment

Seek advice from a speech therapist that works with early speech development. It is never to early to ask questions and get advice. It is better to be told a child is age appropriate than become stressed that your child’s speech is lagging behind their peers. Early intervention can put children’s speech development on the correct path before the above concerns set in.

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Verbal Dyspraxia Symptoms

Verbal Dyspraxia Symptoms

verbal dyspraxia

Verbal Dyspraxia symptoms can vary depending on severity of the speech disorder and the age of the child. Symptoms of developmental verbal dyspraxia or Childhood Apraxia of Speech (CAS) can be difficult to isolate for very young children.  Dyspraxia refers to the difficulties with motor planning i.e., the brain’s messages to muscles are disrupted and so it is hard for children to co-ordinate body and/or speech movements.

​Developmental Verbal Dyspraxia refers to a speech disorder where the motor speech skills are disrupted cause reduced speaking skills and reduced speech clarity.
verbal dyspraxia

It can be hard to definitively diagnosis a child with Developmental Verbal Dyspraxia in young babies and toddlers. This is because a young child’s speech and language skills are still developing. There can be many factors influencing this development from late talking to autism. Developmental Verbal Dyspraxia is considered a speech disorder as it interrupts the typical child speech developmental pathway.

The following list provides key characteristics of Developmental Verbal Dyspraxia. Children may have some or all of the following characteristics of DVD:

  • Late talking or fewer spoken words than expected for age
  • Inconsistent production of the same word e.g., each time a word is said, different errors occur.
  • May have difficulties making sounds on request or repeating back strings of sounds (e.g, ParTar Kar; ParTarKar)
  • Can appear to “get stuck” on saying something i.e. they may “grope” around with their tongues and lips in an effort to move them into the position they need to be to say their target word.
  • Present with a limited number of different types of speech sounds in their developing spontaneous speech
  • Can have difficulties with the rhythm and typical intonation patterns. They may stop and search for ways to say words
  • Vowels frequently do not sound typical
  • May talk slower with more pauses between words
  • Therapy for delayed speech result in slower than expected improvements
  • They have more luck co-ordinating speech sounds in simple words than in connected speech such as sentences (i.e., speech intelligibility decreases the longer the sentence or the fast the rate it is told).
  • They may over use a particular speech sound or substitute sounds with incorrect speech sound pronunciations
  • Current or history of breast, bottle or spoon feeding. They may be slow or messy eaters. Chewing may be unco-ordinated.
  • Delayed development of early speech skills including poor baby babble development.

What to do if you suspect a child has Developmental Verbal Dyspraxia

verbal dyspraxia

It is generally recognised that children with developmental verbal dyspraxia do not get better without profession al support. This can include GPs, Paediatricians and speech pathologists.

​Usually they require regular, direct therapy delivered by a Speech Therapist. Due to the nature of verbal dyspraxia a lot of home practise is required between speech pathology sessions in order to help train the motor speech patterns. SpeechNet provides Language Moment videos as well as downloads with suggestions of how to boost speech skills for specific books and toys.

​SpeechNet Speech Therapists use a range of different therapy approaches to treat children with developmental verbal dyspraxia. Contact SpeechNet today to learn how we can assist children with Developmental Verbal Dyspraxia.

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