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Disorders Diagnosed Early On

The disorders categorized as being usually first diagnosed in childhood include but are not limited to:

This is a separate section in the DSM and is provided for convenience only, not meant to suggest that there is any clear distinction between “childhood” and “adult” disorders. Although most individuals with these disorders seek help during childhood or adolescence, sometimes the disorders are not diagnosed until adulthood.


Mental Retardation
Mental Retardation is a behavioural syndrome related to low intelligence. Onset is usually in infancy or before birth. Before age 18 it’s mental retardation; after 18 yr. it’s a dementia. These two criteria are necessary for a diagnosis:

Causes are:

It affects about 1% of the population. Males outnumber females about three to two. Most (85%) have Mild Mental Retardation (IQ of 50 to 70) and are educable. About 10% have Moderate Mental Retardation (IQ high 30’s to low 50’s) and can learn social and occupational skills but may never be able to live independently. Less than 5% have Severe Mental Retardation (IQ low 20’s to high 30’s) and may learn to perform simple jobs and read a few words. Only 1% – 2% have Profound Mental Retardation (IQ in the low 20’s or below). Co-occurring mental retardation or intellectual disability and mental illness is known as dual diagnosis.


Learning Disorders
People with learning disorders have far more difficulty learning certain academic skills. Diagnosis must be made from a standardized, individualized test. These tests show that a person’s ability to read, do math or write are substantially less than what would be expected for their age, intelligence and education. Learning disorders include:


Pervasive Developmental Disorders (Autism, Rett’s, Asperger’s)
With Pervasive Developmental Disorders, children fail to develop normally in a number of areas, including the ability to:

Autistic Disorder, Rett’s Disorder and Asperger’s Disorder are considered Pervasive Developmental Disorders. A child with Autistic Disorder has impaired social interactions and communications, and stereotyped behaviours and interests. Rett’s Disorder is characterized by slow head growth, delayed language, poorly coordinated gait, and loss of purposeful hand movements and social engagement. Although similar to Autistic Disorder, a child with Asperger’s Disorder does not have delayed/impaired language.


Attention-Deficit/Hyperactivity Disorder
Some mothers say their children kicked more in utero, or cried more as a baby. Symptoms of ADHD (Attention-Deficit Hyperactivity Disorder) typically begin before a child starts school but the disorder is not usually diagnosed until age 9. Children usually have a normal IQ but because of trouble focusing, may not do well in school. Tending to be impulsive they may say things that hurt others’ feelings, making them unpopular. A person with ADHD has trouble sitting quietly and needs to be “on the go.” Many children have a learning disability in reading, and a Conduct Disorder or Oppositional Defiant Disorder. Generally, impulsive behaviour decreases during the teen years, but in some cases, a teen might use substances. Some adults continue to have interpersonal problems, a quick temper, and difficulty dealing with stress.


Conduct Disorder
After 12 months or more of repeatedly violating rules, age-appropriate societal norms or the rights of others, Conduct Disorder may be diagnosed. Three or more of the following behaviours must have occurred in the previous six months:


Oppositional Defiant Disorder
After six or more months if someone shows defiant, hostile, negativistic behaviour, Oppositional Defiant Disorder (ODD) may be diagnosed. The symptoms must impair work, school or social functioning and not occur during a mood or psychotic disorder. As well four or more of the following must be present:


Tourette’s Disorder
Tourette’s Disorder is a Tic Disorder, characterized by one or more vocal tics and multiple motor tics. A “tic” is a movement or vocalization that is non-rhythmic, rapid, repeated, stereotyped, and sudden. Work, social or personal functioning is impaired. Eye blinking is often the first motor tic symptom. Some tics are complex, e.g. someone might do deep knee bends, retrace steps, or twirl while walking. The location and severity of tics can change with time. Vocal tics include barks, clicks, coughs, grunts and understandable words. Between 10% and 30% have “coprolalia,” meaning that they utter obscenities. The average onset is age 7; most have the disorder before age 18. With maturity, many people can suppress their tics, but not for more than three consecutive months.


Separation Anxiety Disorder
If someone experiences excessive anxiety that is inappropriate to their development stage, about being separated from home or the people they’re attached to, a diagnosis of Separation Anxiety Disorder may be made. The symptoms must last for more than four weeks, begin before age 18, impair school, social or personal functioning and do not occur during a pervasive developmental disorder or psychotic disorder. Sometimes the disorder develops after a life stress, e.g. death of relative or pet, move to new neighbourhood. Three or more of the following symptoms must persist/recur:

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