Happy Learners Glossary

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Glossary of terms and abbreviations:

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Child Adolescent Mental Health Service. A UK organisation providing diagnosis, counselling and therapy.


Central Auditory Processing Disorder.

Centile Point

A way of comparing how an individual compares to the general population (or sample). It ranks their score or measurement against the scores or measurements of the population to show at what point in the population they are. For example, someone on the 8th percentile has achieved a very low score which only a small percentage of the population has achieved lower. Someone on the 95 percentile (often abbreviated to 95%ile) would of achieved a very high score greater than 95 per cent of the population. A score between the 17th and the 83rd percentile is considered to be within the average range with the mean average being at 50th percentile. Scores between the 2nd and 16th percentile are often considered below average or moderately low whilst a score below 2nd percentile is significantly low. At the other end of the scale, above 84 is considered above average or moderately high and scores above 98 percentile are classed as extremely high or significantly high.

Central Auditory Processing Disorder

A diagnosis that there is a specific difficulty in one or more of the steps in auditory processing. Children with this disorder will experience difficulty acquiring language through what they hear.

Child Disintegrative Disorder

A very rare condition in which a child experiences the late onset of language, social function and motor skills difficulties after years of apparent normal development.


A strategy for maximising working memory capacity by grouping items together into meaningful chunks. This technique utilises long term memory so that fewer individual items need to be remembered. For example, in remembering a telephone number with a known area code there is no need to hold on to the individual digits of the code as this can be easily recalled from long term memory


Speech that is lacking in fluency due to rapidity and pushing words together

Cognitive Ability

A general statement of how capable a person's mental processes are in dealing with a range of concepts, ideas and stimuli. Usually measured by an IQ test.

Cognitive Function

The ability to perceive meaning from stimuli and manipulate it to understand, learn and generate ideas. It involves thinking, logic and reasoning as well as perception, memory and expression.


This is where an individual has a diagnosis of more than one medical condition. It is usually used where having a particular condition gives an increased probability of having another condition. For example children with ASD have an increased risk of also having ADHD.

Conduct Disorder

Conduct Disorder is a behavioural condition characterised by aggressive interactions with others particularly those in authority.


Any letter of the alphabet other than the vowels A, E, I, O, or U.

Consonant Blend

2 or more consonants that appear together in a word but keep their individual sounds e.g. the "bl" in "black". In general, consonant blends are more difficult to articulate and children may leave out one of the sounds. For example, children may leave out the 's' sound when they say 'school'.


To use socially unacceptable, rude, obscene or offensive language. Coprolalia include the use of swear words.


To make socially unacceptable, rude or obscene movements and gestures.

Corpus callosum

This is the bundle of nerve connections linking the right and left hemispheres of the brain.


A steroid hormone secreted by the adrenal gland involved in increasing blood sugar and suppressing the immune system. It is part of the stress response of the body.

Cri du chat

A genetic disorder caused by a missing part of chromosome 5. the condition is characterised by a cry in babies affected that sounds like a kitten meowing. Children affected will have developmental difficulties affecting them physically, cognitively and behaviourally.

Cross Laterality

Most people are either dominant with their right eye, hand & foot or left eye, hand & foot. People with cross laterality have a mixture and so can be right handed but left footed for example.


Class Teacher

Cued articulation

A signing system used by speech therapists to help children produce the correct sound.


Consonant - Vowel - Consonant. In teaching reading focus is placed on basic letter sound recognition in simple words e.g. C A T - cat.



Disability Discrimination Act. (UK)

Declarative memory

A component of long term memory concerned with remembering facts and knowledge e.g. that the Battle of Hastings was in 1066. Also known as explicit memory it can be sub-divided into episodic and semantic memory.


The medical name for skin picking. Also known as Excoriation Disorder. Chronic picking at the skin is linked to Obsessive Compulsive Disorder.


A difficulty in remaining focussed on a task or activity due to the ease in which other thoughts and sensory inputs intrude on the individual's attention.

Developmental Reading Disorder

Another name for dyslexia, though rarely used.

Disorganised attachment

Children with disorganised attachment tend to be hypervigilant and lack any clear attachment behaviour. This is most frequently a result of parents who are both the source of comfort to their child but also a source of fear through abusive behaviours.


A neurotransmitter that is involved with reward and pleasure.

Duchenne Smile

When the eye muscles as well as the mouth muscles are involved in a smile, this is believed to indicate genuine happiness.


A weakness in the speech muscles that prevents normal movement and leads to an irregular speech pattern.


Dyscalculia is a Specific Learning Difficulty with acquiring mathematical skills and number concepts. Children with dyscalculia struggle to learn and retrieve basic number facts or draw links and understand mathematical relationships between numbers. See page on dyscalculia.


This is a difficulty with handwriting. It can involve an inability to form letters correctly, slowness in the production of writing or tendency to spell words incorrectly.


Dyslexia is form of language disorder characterised by difficulty processing and recalling information, recognising symbols and linking sounds to symbols. It is most often apparent in difficulty with learning to read. It a type of Specific Learning Disorder. See page on dyslexia.


A difficulty naming known objects. Individuals affected display a slower speed of retrieving the name from their long term memory and speaking it.


Developmental dyspraxia is an impairment or immaturity of the organisation of movement. It is an immaturity in the way that the brain processes information, which results in messages not being properly or fully transmitted. The term dyspraxia comes from the word praxis, which means 'doing, acting'. Dyspraxia affects the planning of what to do and how to do it. It is associated with problems of perception, language and thought. (Definition: Dyspraxia Foundation).