Tourette Syndrome: History and Clinical Aspects of Tics
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Transcript Tourette Syndrome: History and Clinical Aspects of Tics
What Is Tourette Syndrome?
A neurological syndrome characterized by
multiple motor and vocal tics with onset before
age 21 years
Tics are involuntary, repetitive, stereotyped
movements that occur many times a day, nearly
every day. Tics typically change anatomic
location, frequency, type, complexity, and
severity over time
Tics can be simple or complex
Behavioral features of TS often include OCD,
ADHD, or both
History of Tourette Syndrome
First report in 1825 by Itard who described a
French noblewoman with body tics, barking
sounds and uncontrollable utterance of
obscenities
Itard also described 7 men and 3 women with
a variety of sudden, bizarre behaviors that we
would now call tics
History of Tourette Syndrome
George Gilles de la Tourette described 8 patients in
1885 who all had motor tics
6 made noises (vocal tics)
5 shouted obscenities (coprolalia)
5 repeated words of others (echolalia)
2 mimicked others gestures (echopraxia)
Itard’s patient became the standard example and
formed the basis for initial conceptualization that
tics were progressive and degenerative
History of Tourette Syndrome
In early 1900s psychoanalytic school become
dominant and attributed tics to repressed
sexual impulses and/or conflict between
parent and child resulting in deficits of will
and character
Alternative views continued to be that tics
were post-rheumatic and a variant of chorea
or were hysterical
History of Tourette Syndrome
In the 1930s, developmental psychologists
described tics as common among schoolage children, but this was largely ignored by
the neurological and psychoanalytic
communities
Observations of heritability and response to
dopamine receptor antagonists began to
suggest a biological basis
Modern View of TS
Tic disorders are biological and likely
involve the basal ganglia
Tourette syndrome is familial with
incomplete penetrance and possibly variable
expression
Once thought to be a simple autosomal
inheritance, it now appears that the genetics are
complex and there are significant environmental
factors
Clinical Features of Tics
Median age of onset is 7 years
Most common initial symptom is eye blinking
(36-48%)
Most common misdiagnoses are eye problems and
allergies
Vocal tics are presenting symptom in 12 - 37%
Severity in childhood does not predict severity in
adulthood
Severity is rarely greater in adulthood than in
childhood
Incidence of TS and Tics
Determination of incidence and prevalence is
complicated
33% of patients with tics do not recognize some or
all of their tics
Parents and teachers may not recognize tics
Recent studies indicate that 5 – 6 % of school
children have tics at some time and that up 0.1 3% have chronic tics (> 1 year)
Natural History of TS and Tics
Tics tend to wax and wane throughout childhood
and adolescence
Tics change in type, frequency and intensity
Long-term prognosis (e.g., early adulthood) quite
favorable:
1/3 of patients experience resolution of tics
1/3 of patients have very mild tics
1/3 of patients continue to have persistent tics
Clinical Features of Tics
Tics are categorized as motor or vocal
Any tic that produces a sounds from the nose of mouth is
a vocal tic
Distinction between motor and vocal is based more on
history than on physiology. Muscle contraction underlies
both types
Motor tics may be abrupt onset and fast ("clonic")
or slow and sustained ("dystonic" or "tonic")
Clinical Features of Tics
Tics are also categorized as simple or
complex
Simple tics are individual movements that
typically look or sounds purposeless
Complex tics resemble purposeful movements or
may be ensembles of more simple movements
The tics are normal movements occurring in
an abnormal context and pattern
Simple Tics
Simple Motor Tics
blinking, nose twitching, head jerking,
blepharospasm, oculogyric movements,
bruxism, torticollis, sustained mouth
opening, abdominal tensing
Simple Vocal Tics
sniffing, throat clearing, grunting,
squeaking, screaming, coughing, blowing
and sucking sounds
Complex Tics
Complex Motor Tics
head shaking, trunk flexion, scratching,
touching, throwing, hitting, jumping, kicking,
obscene gestures (copropraxia) or imitating
gestures (echopraxia)
Complex Vocal Tics
shouting of obscenities or profanities
(coprolalia), repetition of the words of others
(echolalia), repetition of final syllable, word, or
phrase of own words (palilalia)
Clinical Features of Tics
Premonitory feelings or sensory tics occur
in 80% of patients with TS:
Specific sensation (e.g. "itch", "dry
throat")
Nonspecific urge or feeling such as
anxiety
Influencing Factors
Tics may change with emotional or cognitive
state
Decrease with distraction
Increase with stress
Increase during relaxation after a period of stress
May be suppressible with effort; frequent
"rebound" increase afterward
May persist in all stages of sleep
Classification of Tic Disorders DSM-IV
Tourette Syndrome
Multiple motor tics and at least one vocal tic
Intermittently present for > 1 yr
Onset before age 18 yrs
Chronic Motor or Vocal Tic Disorder (presence
of only motor or vocal tics for greater than 12
months)
Transient Tic Disorder (presence of tics for more
than four weeks but less than 12 months)
Tic Disorder Not Otherwise Specified
Associated Symptoms in TS
Majority of patients with TS have symptoms
of ADHD or OCD at some point during the
illness
50% incidence of both ADHD and OCD in
TS (compared to 3-5% in gen. pop.)
These symptoms are often more bothersome
or interfering than tics
Common Obsessive
Symptoms In TS
Frequent and repetitive worrying (e.g., harm
coming to self, family).
Preoccupation with need for order and routine
(e.g., difficulty accepting change).
Repetitive thoughts, words, and phrases.
Urges to perform forbidden or dangerous
activities (e.g., stick finger in fan, hot stove,
etc.).
Indecision, tendency to be unsure of self.
Preoccupation with dirt/contamination
Common Compulsive
Symptoms In TS
Need for order, routine, symmetry (“evening-up”).
Repetitive checking and re-checking (e.g., doors,
appliances, belongings).
Need for perfection, tendency to repetitively
perform same activity to ensure correctness.
Repetitive touching of objects, persons (may be a
complex motor tic).
Cleaning, washing, dressing rituals.
Inability to tolerate certain types of clothing, foods
touch one another on the plate.
Neuropsychology of TS
Intellectual Ability/IQ Testing
Learning Disabilities - Fact or Fiction?
Specific Neuropsychological Deficits
Potential Confounding Factors Influencing
Neuropsychological Function in TS
Intellectual Ability In TS
IQ Scores Normally Distributed in
Epidemiological Studies (Apter et al, 1993)
Below Average IQ Reported in TS Clinic Samples
(Parraga & McDonald, 1996)
Verbal IQ > Performance IQ
– Most studies failed to control for presence of
ADHD or LD (Bornstein, 1990)
PIQ Subtests Primarily Assess Visuospatial
Function and Psychomotor Speed
Learning Disabilities in TS
No Long-Term Outcome Studies of the Learning
Patterns in TS (Walkup et al., 1999)
LD in TS Highly Correlated with Presence of
ADHD (Similar to that reported in ADHD children)
Prevalence of LD in TS Estimated to be 22%
(Erenberg et al., 1986; Abwender et al., 1996)
Math and Written Language Skills Most Common
Areas of Weakness (Burd et al., 1992; Brookshire et
al., 1994; Schuerholz et al., 1996)
School Problems in TS
ADHD Significant Predictor of School Problems in TS
(Abwender et al., 1996)
Higher Rate of Special Education Placement in TS
(Comings et al., 1990; Kurlan et al., 1994)
Kurlan et al., Neurology, 2001:
Epidemiological study of tic prevalence in Monroe
County, NY
1596 students directly evaluated (N=341, Spec. Ed,
N=1255, Reg. Ed)
Spec. Ed - 23.4% weighted prevalence of tics
Reg. Ed – 19.7% weighted prevalence of tics
Neuropsychological Deficits in TS
Visuomotor Deficits
Consistent deficits noted on copying tasks (e.g.,
geometric designs)
10/12 Studies (N=308 TS patients, mean age of ~10
yrs) revealed individual deficits or group differences
on various copying tasks (Schultz et al., 1999)
TS individuals perform about 1.0 SD below age norm
Visuomotor Integration Deficits also Common in ADHD
Children
Neuropsychological Deficits in TS
Gross/Fine Motor Skill
Literature equally compelling and similar
to that reported for visuomotor deficits
Preponderance of studies suggest greater
fine motor skill deficits in TS
Deficits in both TS adults and children
about 0.5-1.0 SD below unaffected controls
(Schultz et al., 1998)
Neuropsychological Deficits in TS
Spatial/Perceptual Deficits
Reported VIQ > PIQ suggest
spatial/perceptual problems in TS (?
confounding factors)
Deficits largely due to difficulty with pure
motor function and/or impaired
visuoperceptual integration (Schultz et al., 1998)
Confounding Factor - Lack of studies
employing motor-free spatial tasks
Neuropsychological Deficits in TS
“Executive” Function (EF)
Loosely defined construct:
mental tracking, sustained attention, working memory
planning and organization
goal-directed behavior
cognitive flexibility
impulse control, self-regulation
EF Deficits also Common in ADHD (Barkley et
al., 1992) and in OCD (Hollander & Wong, 1996;
Rosenberg et al., 1997)
Neuropsychological Deficits in TS
“Executive” Function (EF)
No consistent EF deficit has emerged in TS
Tasks of mental flexibility, planning and sequencing
most commonly cited
Consistent findings of slowed response time on CPT
tasks
Cirino et al., 2000:
No differences in card sorting performance between TS
alone and TS+ADHD
Results suggest that executive dysfunction may occur in
TS independent of co-morbid ADHD
Confounding Factors
Tic Disorder Itself:
Natural history of waxing and waning tics
Active (or passive) tic suppression
Tic suppressing medications (e.g., neuroleptics,
clonidine)
Co-Morbid Conditions (ADHD, OCD)
Methodological Issues (sample sizes, use of
clinic samples)