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Tourette Syndrome




Tourette Syndrome is a chronic

neurochemical disorder that causes involuntary movements and sounds known as tics.




Tourette Syndrome is also commonly known as TS.


Tourette Syndrome is identified as a syndrome because there is no known cause of the disorder.  TS is not a disease.


Tourette Syndrome is considered chronic because the diagnosis requires the tics to be present for at least one year.


TS is described as neurochemical because it is believed to be caused by an abnormal regulation of at least one brain chemical (neurotransmitter) called dopamine.  Very likely other neurotransmitters, such as serotonin, are also involved.


Tics are considered involuntary even though, in some cases, they can be delayed or even prevented entirely with effort.  Some tics, however, are performed without the person being aware of the tic and in other cases, even though the person is aware of the urge to perform the tic, it cannot be delayed or prevented.  Delaying or “holding in” tics may result in a greater expression of the tics at a later time.


The diagnostic criteria for TS requires the presence of both multiple motor and one or more phonic tics at some time, but not necessarily at the same time, lasting for a period of at least one year


A person displaying tics or movements that do not meet the criteria for TS may be diagnosed with another Movement Disorder or Tic Disorder.


Motor tics are movements of parts of the body such as fingers, arms, head and shoulders caused by muscle contraction.


Phonic tics are sounds that may be vocal such as squeaks, throat clearing and words or non-vocal sounds such as sniffing and coughing.


People with TS share the common symptom of tics, however, no two people will share the exact same tics.  Symptoms of TS and associated disorders and behaviours will look different from person to person.


Symptoms will vary from mild to severe and may disappear completely at times.



Part of a Family of Disorders:


Tourette Syndrome disorder is part of a larger spectrum of disorders known as Movements Disorders.


Movement Disorders include Chorea, Dystonia, Myoclonus, Seizure Disorders, Tic Disorders, and Tremor.


There is no evidence that Tourette Syndrome is linked to other than Tic Disorders.


Most physicians familiar with Movement Disorders will quickly separate a Tic Disorder from other Movement Disorders


Tic Disorders include subtypes:


    Chronic Tic Disorder,


    Tourette Syndrome, and

    Transient Tic Disorder.


The majority of diagnoses of Tourette Syndrome will be made based on the history (past behaviours) of the patient as reported by either the patient or in the case of children, by the parents of the child.  Observations of the patient during the visit will also be used in the diagnosis.


Separating Tourette Syndrome from other Tic Disorders is a matter of looking at the current diagnostic criteria of Tourette Syndrome as defined by the Diagnostic and Statistical Manual of Mental Disorders (DSM.)



Associated Disorders:


Tourette Syndrome may be present in a person as a lone condition which may be described as “TS-Only” or “Pure TS” but is more often accompanied by another diagnosable medical condition that is often referred to as being a co-morbid condition or an associated disorder.


The most common associated disorders are Obsessive Compulsive Disorder and Attention Deficit Hyperactivity Disorder and the variations of these conditions.


It is important to understand the conditions and the differences between the conditions and which condition a given symptom or behaviour belongs to.  Treatment, whether psychological or medical, is specific to the condition.





TS is believed to be genetically transmitted.


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