A look at the similarities and differences between autism spectrum disorders and Tourette's, including lists and tables from various medical sources for helping to distinguish stereotypies, stims and tics.
Tics are a feature of autism spectrum disorders. Further complication in diagnosis is introduced because tics may not be adequately distinguished from the stims and stereotypies of the autism spectrum by all physicians.
One physician (Roger Kurlan) estimated at the 1998 TSA conference that up to 1/3 of the patients he saw in a tertiary referral clinic for Tourette's were actually misdiagnosed cases of autism spectrum disorders, and that the patients didn't actually have primary, genetic, inherited Tourette's. That is not the same as saying that 1/3 of persons with Tourette's have autism, or that the two can never co-occur: it just means that in a specialty referral clinic where the more difficult cases are more typically seen, 1/3 of those patients may have been misdiagnosed with Tourette's before they reached tertiary, specialty, clinical attention, where it was found that their tics were fully and better explained by an autism spectrum diagnosis.
If tics are fully explained by another diagnosis, then the diagnosis of Tourette's is unnecessary and may add nothing to the treatment options. If tics are better explained by another medical condition such as autism, then a Tourette's diagnosis would be incorrect unless it is felt that both conditions were separately inherited, as occurs in a few cases.
The two conditions may co-occur in a few instances, but more typically, autism spectrum disorders are misdiagnosed as Tourette's, when the tics are fully explainable by an autism spectrum disorder. There was a journal report of a higher than expected chance that children with autism will also meet the diagnostic criteria for tic disorders Kerbeshian and Burd on TS/Autism Comorbidity , but 1) epidemiologic studies have not been done, 2) subsequent work has shown that the rate may not have been higher than expected (rather, the prevalance rate of Tourette's has been underestimated), and 3) that is not the same as saying that Tourette's and autism are on the same spectrum. It only means that more children with autism may have tourettism (tics that "look like" primary, genetic Tourette's).
www.tourettesyndrome.net/aspergers_comorbidity.htm
"Baron-Cohen et al. systematically assessed over 400 autistic students in special schools for children with autism and found that over 4% had definite Tourette and another 2+% had probable Tourette's. In their discussion, they discuss the higher-than-expected rate and raised the possibility that Autism/Asperger's and Tourette's might be associated.
At the time they published their findings, the rate they found was, indeed, significantly higher than the generally accepted rate of Tourette's in the general population. Subsequently, however, Roger Kurlan and his colleagues (2001) published data on Tourette's Syndrome in children and adolescents that found a 3% rate in general education and a rate of over 7% in special education.
In light of Dr. Kurlan's data, the data from the Baron-Cohen et al. study do not provide evidence that autism and Tourette's are associated disorders. Thus, children with Autism or AD may have tics or TS as comorbid conditions, but we have not yet seen any evidence to suggest that this occurs significantly more often than could be accounted for by the individual rates of these disorders in the population." Leslie Packer, PhD, October, 2004, tourettesyndrome.net/aspergers_comorbidity.htm
Tics are part of autism spectrum disorders. Here is an excerpt from a table from an article by the same authors (Kerbeshian and Burd) of many of the journal reports on comorbidity between autism and Tourette's, indicating that autism spectrum disorders are one of many secondary causes of tics (that is, a cause of tics other than primary, genetic Tourette's syndrome):
Recognition and Management of Tourette's Syndrome and Tic Disorders
MOHAMMED M. BAGHERI, M.D., JACOB KERBESHIAN, M.D., and LARRY BURD, PH.D.
University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota
TABLE 5
Secondary Causes of Tic Disorders
Schizophrenia
Asperger's syndrome/autism
Mental retardation
Kumar R, Lang AE. Tourette syndrome. Secondary tic disorders. Neurol Clin 1997;15:309-31.
A look at the differences between TS and autism:
Tourette Syndrome, Advances in Neurology, Vol. 85.
Editors, Donald J. Cohen, MD, Joseph Jankovic, MD, Christopher G. Goetz, MD.
Lippincott, Williams & Wilkins, November, 2000.
ISBN: 0-7817-2405-8
Pages: 432, Price: $149.00
Chapter 7: Autism Spectrum Disorders: Relevance to Tourette Syndrome, Isabelle Rapin
The autistic spectrum disorders and Tourette Syndrome (TS) are two distinct, complex, behaviorally defined disorders of childhood ...
... a few individuals fulfill criteria for both TS and an autistic spectrum disorder.
It is in nonretarded, rigid individuals on the autistic spectrum, especially those with so-called Asperger syndrome, that differences with less severely affected individuals with TS and OCD may become blurred, or that both disorders may coexist.
The defining social deficits of autism consist of seriously defective interpersonal skills, notably in interaction with peers; dininterest in social contact or gauche, inept social approaches; and lack of insight into other persons' feelings and intentions -- deficient 'theory of mind,' none of which is characterisitic of TS.
Common stereotypies in children with autism include hand flapping, jumping, pacing, running around in circles, rocking from one foot to the other, body swaying, banging the head, rubbing and drumming the fingers, twindling a lock of hair or a string, looking out of the corner of the eyes, screwing up the face, tightening the whole body, and many others. The stereotypic vocalizations in autism are more likely to be humming, whispering, or jargon without communicative intent, rather than the respiratory tics, loud whistles or screeches, or the coprolalia of some individuals with TS.
Table 7.1 Some major differences between Tourette Syndrome and autism
(AD = autism spectrum disorders)
TS: Problems in sociability absent or secondary to the social consequences of the disorder.
AD: Core deficit universally present throughout inidvidual's lifespan.
TS: No language/communication disorder.
AD: Core deficit. Language delayed and impaired in all but those children with Asperger syndrome, whose higher-order comprehension and prosody may nevertheless be impaired.
TS: Frequent but not universal association with obsessive-compulsive disorder.
AD: Perseveration, rigidity, narrow focus of interest, and obsessions are core deficits.
TS: Not associated with mental retardation, but academic deficits frequent.
AD: Mental retardation frequent but not universal. Uneven cognitive profile.
TS: Frequent association with attention-deficit hyperactivity disorder.
AD: Major deficit in joint attention; attention deficit in some children with few skills. Hyperfocused attention to self-generated pursuits in some individuals.
TS: Not associated with epilepsy.
AD: Epilepsy reported in one-third of affected individuals by adulthood, linked with severity of brain dysfunction.
Table 7.2 Characteristics of the movement disorders of Tourette Syndrome (tics) versus autism (stereotypies)
T = tics
S = stereotypies
T: Universal
S: Frequent, not universal
T: School-age onset
S: Toddler onset
T: May remit for months
S: More persistent; may become miniaturized with age
T: Vary a great deal over time
S: Less variable
T: Preceded by urge
S: May be preceded by urge
T: Suppressible for a time
S: Suppressible for a time
T: Sudden, rapid, darting
S: Not as abrupt or rapid
T: Brief
S: Longer
T: Repetitive, irregular
S: Repetitive, rhythmical
T: Asymmetrical
S: Often (not always) bilateral or generalized (e.g., flapping, jumping, pacing)
T: May be small (simple tics) and inconspicuous, or bizarre, even grotesque (complex tics)
S: May be simple or complex. More gesture-like or manneristic
T: Frequency and severity unrelated to IQ
S: More frequent in individuals with low IQ
T: Self-injury uncommon, "accidental," e.g., by repetitive poking
S: Self-injury relatively frequent, "intended"; e.g., biting, picking, head banging, slapping. Associated with low IQ and aggressiveness in some but not all individuals.
T: Not deliberately aggressive; sudden compulsive touching or approaching others.
S: Aggression such as pinching or hitting frequent
T: Respiratory tics, sudden vocalizations, coprolalia
S: Humming, singing, muttering
T: Worsened by anxiety
S: Worsened by anxiety, idleness
T: Lessened by activity, concentration
S: Lessened by activity, concentration
T: May persist in sleep
S: Not present in sleep
Information typed by someone who attended his presentation, from a handout from Dr Singer at Hopkins on Stereotypies.
**********************
Stereotypies
Harvey Singer, M.D.
Stereotypies are involuntary, patterned, purposeless, repetitive, rhythmic, movements. They must be differentiated from several other movement disorders including habits, mannerisms, complex motor tics and obsessive compulsive behavior.
Stereotypies often begin in infancy and involve bursts of repetitive movements typically the arms or hands (e.g., recurrent arm flapping, hand waving, hand twisting), with body rocking and leg shaking as common features. Episodes last for second to minutes, and usually occur in clusters at frequent intervals throughout the day. Movements have a fixed pattern, are generally associated with periods of excitement, stress, boredom or fatigue, and can be readily suppressed by a sensory stimulus or distraction.
The affected child typically denies preceding sensory phenomena and any interference of daily activities caused by the movement. Despite lack of concern by the patient, the parents are often distressed and anxious about potential psychosocial difficulties. Stereotypic movements can occur in normal children or in those with sensory deficits such as deafness or blindness. Previous reports have inaccurately described stereotypies as strictly occurring with mental retardation, autism, schizophrenia, tardive dyskinesia or neurodegenerative diseases.
Stereotypies must frequently be distinguished from complex motor tics, which are abrupt movements that involve either a cluster of simple motor tics, or a more coordinated sequence of movements. Some complex tics clearly have no purpose, (facial, body contortion), whereas others may appear purposeful, but are not (touching, smelling, jumping, turning).
Several characteristics may help to differentiate stereotypies from tics;
1) stereotypies have an earlier age of onset (<2 years) than do tics (mean onset 6-7 years);
2) they are more constant and fixed in their pattern as compared to the more variable action of tics;
3) they involve arms, hands, or the entire body rather than eye blinks, facial grimaces, head twists or shoulder shrugs;
4) they are more rhythmic, with flapping and waving, than are tics which tend to be rapid and random;
5) they are more continuous and prolonged in duration, although some complex tics may also have this character;
6) stereotypies are not associated with premonitory urges or desires to reduce an inner tension;
7) although both may occur during periods of excitement or stress, stereotypic movements often occur when the child is engrossed in an activity e.g., playing with a toy, computer game, or visiting an arcade),;
8 ) stereotypies can be stopped by distraction, although rarely is there a voluntary conscious effort to control. Tics are briefly suppressible but result in a build-up of inner tension;
9) stereotypies are generally less responsive whereas tic disorders are frequently familial with a positive history in about half of the cases. Stereotypies can be found in patients with tics or even TS.
Stereotypies have a variable course - some gradually resolve, whereas others remain static. Although dopaminergic and serotonergic mechanisms have been postulated, the underlying pathophysiology, especially in otherwise normal children, is unknown. EEG and MRI studies are normal. Pharmacotherapy is usually not indicated. Some stereotypies respond to dopamine blocking agents, clonazepam, clonidine, or serotonin reuptake inhibitors although the response is variable.
References:
Berkson G. Rafaeli-Mor N, Tarnovsky S: Body-rocking and other habits of college students and persons with mental retardation. Am J Ment Retard 104:107-16, 1999.
Campos-Castello J. Stereotypies, Acta Neuropediatr 2:177-185, 1996.
Cho AK, Melega WP, Kuczenski R, Segal DS, Schmitz DA: Caudate-putamen dopamine and stereotypy response profiles after intravenous and subcutaneous amphetamine. Synapase 31:125-33, 1999.
Razzi E, Lanners J, Danova S, Ferrarri-Ginevra O, Gheza C, Lupaaria A, Balottin U, Lanzi G: Sterotyped behaviours in blind children. Brain Dev 21:522-8, 1999.
Frank LM. Gratification phenomena: a common but infrequently recognized movement disorder in childhood. Ann Neurol 36:536, 1994.
Jankovic J. Stereotypies. In: Marsden CD, Fahn S (eds).:Movement Disorder3. Oxford: Butterworth-Heinemann, 1994; pp503-517.
Tan A, Salgado M, Fahn S: The characterization and outcome of stereotypic movements in nonautistic children. Mov Disord. 12:47-52, 1997.
Good links from Lara (thanks :-)
Stereotypic behaviors of autism
Tunnel Vision in Autism
Tics are a feature of autism spectrum disorders. Further complication in diagnosis is introduced because tics may not be adequately distinguished from the stims and stereotypies of the autism spectrum by all physicians.
One physician (Roger Kurlan) estimated at the 1998 TSA conference that up to 1/3 of the patients he saw in a tertiary referral clinic for Tourette's were actually misdiagnosed cases of autism spectrum disorders, and that the patients didn't actually have primary, genetic, inherited Tourette's. That is not the same as saying that 1/3 of persons with Tourette's have autism, or that the two can never co-occur: it just means that in a specialty referral clinic where the more difficult cases are more typically seen, 1/3 of those patients may have been misdiagnosed with Tourette's before they reached tertiary, specialty, clinical attention, where it was found that their tics were fully and better explained by an autism spectrum diagnosis.
If tics are fully explained by another diagnosis, then the diagnosis of Tourette's is unnecessary and may add nothing to the treatment options. If tics are better explained by another medical condition such as autism, then a Tourette's diagnosis would be incorrect unless it is felt that both conditions were separately inherited, as occurs in a few cases.
The two conditions may co-occur in a few instances, but more typically, autism spectrum disorders are misdiagnosed as Tourette's, when the tics are fully explainable by an autism spectrum disorder. There was a journal report of a higher than expected chance that children with autism will also meet the diagnostic criteria for tic disorders Kerbeshian and Burd on TS/Autism Comorbidity , but 1) epidemiologic studies have not been done, 2) subsequent work has shown that the rate may not have been higher than expected (rather, the prevalance rate of Tourette's has been underestimated), and 3) that is not the same as saying that Tourette's and autism are on the same spectrum. It only means that more children with autism may have tourettism (tics that "look like" primary, genetic Tourette's).
www.tourettesyndrome.net/aspergers_comorbidity.htm
"Baron-Cohen et al. systematically assessed over 400 autistic students in special schools for children with autism and found that over 4% had definite Tourette and another 2+% had probable Tourette's. In their discussion, they discuss the higher-than-expected rate and raised the possibility that Autism/Asperger's and Tourette's might be associated.
At the time they published their findings, the rate they found was, indeed, significantly higher than the generally accepted rate of Tourette's in the general population. Subsequently, however, Roger Kurlan and his colleagues (2001) published data on Tourette's Syndrome in children and adolescents that found a 3% rate in general education and a rate of over 7% in special education.
In light of Dr. Kurlan's data, the data from the Baron-Cohen et al. study do not provide evidence that autism and Tourette's are associated disorders. Thus, children with Autism or AD may have tics or TS as comorbid conditions, but we have not yet seen any evidence to suggest that this occurs significantly more often than could be accounted for by the individual rates of these disorders in the population." Leslie Packer, PhD, October, 2004, tourettesyndrome.net/aspergers_comorbidity.htm
Tics are part of autism spectrum disorders. Here is an excerpt from a table from an article by the same authors (Kerbeshian and Burd) of many of the journal reports on comorbidity between autism and Tourette's, indicating that autism spectrum disorders are one of many secondary causes of tics (that is, a cause of tics other than primary, genetic Tourette's syndrome):
Recognition and Management of Tourette's Syndrome and Tic Disorders
MOHAMMED M. BAGHERI, M.D., JACOB KERBESHIAN, M.D., and LARRY BURD, PH.D.
University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota
TABLE 5
Secondary Causes of Tic Disorders
Schizophrenia
Asperger's syndrome/autism
Mental retardation
Kumar R, Lang AE. Tourette syndrome. Secondary tic disorders. Neurol Clin 1997;15:309-31.
A look at the differences between TS and autism:
Tourette Syndrome, Advances in Neurology, Vol. 85.
Editors, Donald J. Cohen, MD, Joseph Jankovic, MD, Christopher G. Goetz, MD.
Lippincott, Williams & Wilkins, November, 2000.
ISBN: 0-7817-2405-8
Pages: 432, Price: $149.00
Chapter 7: Autism Spectrum Disorders: Relevance to Tourette Syndrome, Isabelle Rapin
The autistic spectrum disorders and Tourette Syndrome (TS) are two distinct, complex, behaviorally defined disorders of childhood ...
... a few individuals fulfill criteria for both TS and an autistic spectrum disorder.
It is in nonretarded, rigid individuals on the autistic spectrum, especially those with so-called Asperger syndrome, that differences with less severely affected individuals with TS and OCD may become blurred, or that both disorders may coexist.
The defining social deficits of autism consist of seriously defective interpersonal skills, notably in interaction with peers; dininterest in social contact or gauche, inept social approaches; and lack of insight into other persons' feelings and intentions -- deficient 'theory of mind,' none of which is characterisitic of TS.
Common stereotypies in children with autism include hand flapping, jumping, pacing, running around in circles, rocking from one foot to the other, body swaying, banging the head, rubbing and drumming the fingers, twindling a lock of hair or a string, looking out of the corner of the eyes, screwing up the face, tightening the whole body, and many others. The stereotypic vocalizations in autism are more likely to be humming, whispering, or jargon without communicative intent, rather than the respiratory tics, loud whistles or screeches, or the coprolalia of some individuals with TS.
Table 7.1 Some major differences between Tourette Syndrome and autism
(AD = autism spectrum disorders)
TS: Problems in sociability absent or secondary to the social consequences of the disorder.
AD: Core deficit universally present throughout inidvidual's lifespan.
TS: No language/communication disorder.
AD: Core deficit. Language delayed and impaired in all but those children with Asperger syndrome, whose higher-order comprehension and prosody may nevertheless be impaired.
TS: Frequent but not universal association with obsessive-compulsive disorder.
AD: Perseveration, rigidity, narrow focus of interest, and obsessions are core deficits.
TS: Not associated with mental retardation, but academic deficits frequent.
AD: Mental retardation frequent but not universal. Uneven cognitive profile.
TS: Frequent association with attention-deficit hyperactivity disorder.
AD: Major deficit in joint attention; attention deficit in some children with few skills. Hyperfocused attention to self-generated pursuits in some individuals.
TS: Not associated with epilepsy.
AD: Epilepsy reported in one-third of affected individuals by adulthood, linked with severity of brain dysfunction.
Table 7.2 Characteristics of the movement disorders of Tourette Syndrome (tics) versus autism (stereotypies)
T = tics
S = stereotypies
T: Universal
S: Frequent, not universal
T: School-age onset
S: Toddler onset
T: May remit for months
S: More persistent; may become miniaturized with age
T: Vary a great deal over time
S: Less variable
T: Preceded by urge
S: May be preceded by urge
T: Suppressible for a time
S: Suppressible for a time
T: Sudden, rapid, darting
S: Not as abrupt or rapid
T: Brief
S: Longer
T: Repetitive, irregular
S: Repetitive, rhythmical
T: Asymmetrical
S: Often (not always) bilateral or generalized (e.g., flapping, jumping, pacing)
T: May be small (simple tics) and inconspicuous, or bizarre, even grotesque (complex tics)
S: May be simple or complex. More gesture-like or manneristic
T: Frequency and severity unrelated to IQ
S: More frequent in individuals with low IQ
T: Self-injury uncommon, "accidental," e.g., by repetitive poking
S: Self-injury relatively frequent, "intended"; e.g., biting, picking, head banging, slapping. Associated with low IQ and aggressiveness in some but not all individuals.
T: Not deliberately aggressive; sudden compulsive touching or approaching others.
S: Aggression such as pinching or hitting frequent
T: Respiratory tics, sudden vocalizations, coprolalia
S: Humming, singing, muttering
T: Worsened by anxiety
S: Worsened by anxiety, idleness
T: Lessened by activity, concentration
S: Lessened by activity, concentration
T: May persist in sleep
S: Not present in sleep
Information typed by someone who attended his presentation, from a handout from Dr Singer at Hopkins on Stereotypies.
**********************
Stereotypies
Harvey Singer, M.D.
Stereotypies are involuntary, patterned, purposeless, repetitive, rhythmic, movements. They must be differentiated from several other movement disorders including habits, mannerisms, complex motor tics and obsessive compulsive behavior.
Stereotypies often begin in infancy and involve bursts of repetitive movements typically the arms or hands (e.g., recurrent arm flapping, hand waving, hand twisting), with body rocking and leg shaking as common features. Episodes last for second to minutes, and usually occur in clusters at frequent intervals throughout the day. Movements have a fixed pattern, are generally associated with periods of excitement, stress, boredom or fatigue, and can be readily suppressed by a sensory stimulus or distraction.
The affected child typically denies preceding sensory phenomena and any interference of daily activities caused by the movement. Despite lack of concern by the patient, the parents are often distressed and anxious about potential psychosocial difficulties. Stereotypic movements can occur in normal children or in those with sensory deficits such as deafness or blindness. Previous reports have inaccurately described stereotypies as strictly occurring with mental retardation, autism, schizophrenia, tardive dyskinesia or neurodegenerative diseases.
Stereotypies must frequently be distinguished from complex motor tics, which are abrupt movements that involve either a cluster of simple motor tics, or a more coordinated sequence of movements. Some complex tics clearly have no purpose, (facial, body contortion), whereas others may appear purposeful, but are not (touching, smelling, jumping, turning).
Several characteristics may help to differentiate stereotypies from tics;
1) stereotypies have an earlier age of onset (<2 years) than do tics (mean onset 6-7 years);
2) they are more constant and fixed in their pattern as compared to the more variable action of tics;
3) they involve arms, hands, or the entire body rather than eye blinks, facial grimaces, head twists or shoulder shrugs;
4) they are more rhythmic, with flapping and waving, than are tics which tend to be rapid and random;
5) they are more continuous and prolonged in duration, although some complex tics may also have this character;
6) stereotypies are not associated with premonitory urges or desires to reduce an inner tension;
7) although both may occur during periods of excitement or stress, stereotypic movements often occur when the child is engrossed in an activity e.g., playing with a toy, computer game, or visiting an arcade),;
8 ) stereotypies can be stopped by distraction, although rarely is there a voluntary conscious effort to control. Tics are briefly suppressible but result in a build-up of inner tension;
9) stereotypies are generally less responsive whereas tic disorders are frequently familial with a positive history in about half of the cases. Stereotypies can be found in patients with tics or even TS.
Stereotypies have a variable course - some gradually resolve, whereas others remain static. Although dopaminergic and serotonergic mechanisms have been postulated, the underlying pathophysiology, especially in otherwise normal children, is unknown. EEG and MRI studies are normal. Pharmacotherapy is usually not indicated. Some stereotypies respond to dopamine blocking agents, clonazepam, clonidine, or serotonin reuptake inhibitors although the response is variable.
References:
Berkson G. Rafaeli-Mor N, Tarnovsky S: Body-rocking and other habits of college students and persons with mental retardation. Am J Ment Retard 104:107-16, 1999.
Campos-Castello J. Stereotypies, Acta Neuropediatr 2:177-185, 1996.
Cho AK, Melega WP, Kuczenski R, Segal DS, Schmitz DA: Caudate-putamen dopamine and stereotypy response profiles after intravenous and subcutaneous amphetamine. Synapase 31:125-33, 1999.
Razzi E, Lanners J, Danova S, Ferrarri-Ginevra O, Gheza C, Lupaaria A, Balottin U, Lanzi G: Sterotyped behaviours in blind children. Brain Dev 21:522-8, 1999.
Frank LM. Gratification phenomena: a common but infrequently recognized movement disorder in childhood. Ann Neurol 36:536, 1994.
Jankovic J. Stereotypies. In: Marsden CD, Fahn S (eds).:Movement Disorder3. Oxford: Butterworth-Heinemann, 1994; pp503-517.
Tan A, Salgado M, Fahn S: The characterization and outcome of stereotypic movements in nonautistic children. Mov Disord. 12:47-52, 1997.
Good links from Lara (thanks :-)
Stereotypic behaviors of autism
Tunnel Vision in Autism
