Showing papers on "Tourette syndrome published in 2006"
TL;DR: Carefully screened groups of pathological gamblers and alcohol dependents were characterized by diminished executive functioning, suggesting a dysfunction of frontal lobe circuitry in these disorders.
Abstract: Aims Neurocognitive functions in pathological gambling have relevance for the aetiology and treatment of this disorder, yet are poorly understood. This study therefore investigated neurocognitive impairments of executive functions in a group of carefully screened Diagnostic and Statistical Manual version IV (DSM-IV-TR) pathological gamblers. Performance was compared to a group of normal control participants. To study the specificity of these neurocognitive deficits, a substance dependence group (alcohol dependence) and an impulse control disorder group (Tourette syndrome) were included. Design Cross-sectional study. Setting Addiction and general mental health treatment centres. Participants Forty-nine pathological gamblers, 48 abstinent alcohol-dependent patients, 46 participants with Tourette syndrome and 49 normal control participants. Measurements A comprehensive neuropsychological battery measuring executive functions as well as basic cognitive functions. Findings Both the pathological gambling and the alcohol dependent groups were characterized by diminished performance on inhibition, time estimation, cognitive flexibility and planning tasks. The Tourette syndrome group showed deficits only on inhibition tasks. Basic cognitive functions were intact in all clinical groups. Comorbid attention deficit hyperactivity disorder, antisocial personality disorder and nicotine dependence influenced the impaired functions of the clinical groups only minimally. Conclusions Carefully screened groups of pathological gamblers and alcohol dependents were characterized by diminished executive functioning, suggesting a dysfunction of frontal lobe circuitry in these disorders. The resemblance between the pathological gambling group and the alcohol dependence group suggests a common neurocognitive aetiology for these disorders. Psychosocial treatment of these disorders could benefit from assessing and targeting deficits in executive functions, as they probably influence the course of these disorders negatively.
460 citations
TL;DR: Basic research on striatal inhibitory mechanisms and dopaminergic function complements the recent neuroimaging and anatomical data on TS and provides new pieces to the TS puzzle.
446 citations
TL;DR: Obsessive-compulsive disorder symptoms in children with TS became more severe at a later age and were more likely to persist than tic symptoms.
Abstract: Background Tourette syndrome (TS) is a childhood-onset neuropsychiatric disorder that is characterized by both motor and phonic tics. One half to two thirds of children with TS experience a reduction or complete resolution of tic symptoms during adolescence. At least one third of adults with TS have comorbid obsessive-compulsive disorder (OCD). Objectives To clarify the clinical course of tic and OCD symptoms in children with TS and determine if baseline clinical measurements in childhood are associated with future symptom severity in late adolescence and early adulthood. Design Prospective cohort study. Setting Yale Child Study Center tic and OCD outpatient specialty clinic. Participants Forty-six children with TS who received a structured clinical evaluation prior to age 14 years. Main Outcome Measures Expert-rated tic and OCD symptom severity at follow-up interview an average of 7.6 years later (range, 3.8-12.8 years). Results Eighty-five percent of subjects reported a reduction in tic symptoms during adolescence. Only increased tic severity in childhood was associated with increased tic severity at follow-up. The average age at worst-ever tic severity was 10.6 years. Forty-one percent of patients with TS reported at one time experiencing at least moderate OCD symptoms. Worst-ever OCD symptoms occurred approximately 2 years later than worst-ever tic symptoms. Increased childhood IQ was strongly associated with increased OCD severity at follow-up. Conclusion Obsessive-compulsive disorder symptoms in children with TS became more severe at a later age and were more likely to persist than tic symptoms.
404 citations
TL;DR: The results of this study indicate that paralimbic and sensory association areas are critically implicated in tic generation, similar to movements triggered internally by unpleasant sensations, as has been shown for pain or itching.
Abstract: Little is known about the neural correlates of tics and associated urges. In the present study, we aimed to explore the neural basis of tics in patients with Tourette syndrome by using event-related functional MRI (fMRI). Ten patients (6 women, 4 men; age: mean +/- SD = 31 +/- 11.2) were studied while spontaneously exhibiting a variety of motor and vocal tics. On the basis of synchronized video/audio recordings, fMRI activities were analysed 2 s before and at tic onset irrespective of the clinical phenomenology. We identified a brain network of paralimbic areas such as anterior cingulate and insular cortex, supplementary motor area (SMA) and parietal operculum (PO) predominantly activated before tic onset (P < 0.05, corrected for multiple comparisons). In contrast, at the beginning of tic action, significant fMRI activities were found in sensorimotor areas including superior parietal lobule bilaterally and cerebellum. The results of this study indicate that paralimbic and sensory association areas are critically implicated in tic generation, similar to movements triggered internally by unpleasant sensations, as has been shown for pain or itching.
374 citations
TL;DR: It is concluded that accurate diagnosis, including identification of comorbid conditions, is an essential step toward appropriate treatment for patients with TS and the evidence supporting efficacy and safety for medications used in patients withTS varies.
Abstract: To develop a guide to clinical assessment and pharmacotherapy for children and adults with Tourette syndrome (TS), we reviewed published literature over the past 25 years to identify original articles and reviews on the assessment and pharmacological treatment of Tourette syndrome, attention—deficit/hyperactivity disorder (ADHD) and obsessive—compulsive disorder (OCD). The literature search also included a survey of reviews published in book chapters. The assessment section was compiled from several reviews. Pharmacological treatments were classified into those with strong empirical support (as evidenced by two positive placebo-controlled studies for tics, OCD, or ADHD in TS samples); modest empirical support (one positive placebo-controlled study), or minimal support (open-label data only). We conclude that accurate diagnosis, including identification of comorbid conditions, is an essential step toward appropriate treatment for patients with TS. In many patients with TS, symptom management requires pharmacotherapy for tics or coexisting conditions. The evidence supporting efficacy and safety for medications used in patients with TS varies. But this evidence offers the best guide to clinical practice.
273 citations
TL;DR: With identification of specific genes of major effect and advances in the understanding of the neural circuitry of sensorimotor gating, habit formation, and procedural memory—together with insights from postmortem brain studies, in vivo brain imaging, and electrophysiologic recordings—the authors might be on the threshold of a deeper understand of the phenomenology and natural history of Tourette syndrome.
Abstract: Tourette syndrome is a neurodevelopmental disorder characterized by motor and vocal tics--rapid, repetitive, stereotyped movements or vocalizations. Tourette syndrome typically has a prepubertal onset, and boys are more commonly affected than girls. Symptoms usually begin with transient bouts of simple motor tics. By age 10 years, most children are aware of nearly irresistible somatosensory urges that precede the tics. These urges likely reflect a defect in sensorimotor gating because they intrude into the child's conscious awareness and become a source of distraction and distress. A momentary sense of relief typically follows the completion of a tic. Over the course of hours, tics occur in bouts, with a regular intertic interval. Tics increase during periods of emotional excitement and fatigue. Tics can become "complex" in nature and appear to be purposeful. Tics can be willfully suppressed for brief intervals and can be evoked by the mere mention of them. Tics typically diminish during periods of goal-directed behavior, especially those that involve both heightened attention and fine motor or vocal control, as occur in musical and athletic performances. Over the course of months, tics wax and wane. New tics appear, often in response to new sources of somatosensory irritation, such as the appearance of a persistent vocal tic (a cough) following a cold. Over the course of years, tic severity typically peaks between 8 and 12 years of age. By the end of the second decade of life, many individuals are virtually tic free. Less than 20% of cases continue to experience clinically impairing tics as adults. Tics rarely occur in isolation, and other coexisting conditions--such as behavioral disinhibition, hypersensitivity to a broad range of sensory stimuli, problems with visual motor integration, procedural learning difficulties, attention-deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder, depression, anxiety, and emotional instability--are often a greater source of impairment than the tics themselves. Emerging behavioral treatments of Tourette syndrome are based in part on an understanding of the moment-to-moment experience of somatosensory urges and motor response. With identification of specific genes of major effect and advances in our understanding of the neural circuitry of sensorimotor gating, habit formation, and procedural memory--together with insights from postmortem brain studies, in vivo brain imaging, and electrophysiologic recordings--we might be on the threshold of a deeper understanding of the phenomenology and natural history of Tourette syndrome.
219 citations
TL;DR: Surgical candidates should receive a comprehensive evaluation before surgery to ensure that DBS is clearly the appropriate clinical treatment choice and that early clinical experience will be documented publicly to facilitate rational decision‐making for both clinical care and future clinical trials.
Abstract: In response to recent publicity regarding the potential use of deep brain stimulation (DBS) for reducing tic severity in Tourette's syndrome (TS), the Tourette Syndrome Association convened a group of TS and DBS experts to develop recommendations to guide the early use and potential clinical trials of DBS for TS and other tic disorders. The goals of these recommendations are to ensure that all surgical candidates are (1) fully informed about the risks, benefits, and alternative treatments available; (2) receive a comprehensive evaluation before surgery to ensure that DBS is clearly the appropriate clinical treatment choice; and (3) that early clinical experience will be documented publicly to facilitate rational decision-making for both clinical care and future clinical trials.
213 citations
TL;DR: The results suggest that HR has specific tic-reducing effects although SP is effective in improving life-satisfaction and psychosocial functioning.
173 citations
TL;DR: It is shown for the first time that young people with TS exhibit paradoxically greater levels of cognitive control over their movements than their age-matched controls and may indicate a subcortical locus for the triggering of tics.
159 citations
TL;DR: This model is consistent with all of the present knowledge about ADHD including the increased frequency of ADHD in the relatives of ADHD probands, the presence of a wide spectrum of comorbid behaviors, the small percentage of the variance of specific behaviors accounted for by each gene, and numerous other aspects of ADHD.
Abstract: ADHD is a polygenic disorder due to the additive effect of genes affecting dopamine, norepinephrine, serotonin, GABA, and other neurotransmitters. Some of the specific loci involved are dopamine genes--DRD2, DRD4, DRD5, and the dopamine transporter; norepinephrine (NE) and epinephrine (EPI) genes--dopamine beta-hydroxylase, ADRA2A, ADRA2C, PNMT, norepinephrine transporter, MAOA, COMT; serotonin genes--TDO2, HTR1A, HTR1DA, serotonin transporter; GABA genes--GABRB3; androgen receptor and other genes. This model is consistent with all of the present knowledge about ADHD including (a) the increased frequency of ADHD in the relatives of ADHD probands, (b) the presence of a wide spectrum of comorbid behaviors (depression, anxiety, learning, conduct, oppositional-defiant, conduct and substance abuse disorders) in ADHD probands and their relatives on both parental sides, (c) the close relationship to Tourette syndrome (TS), (d) the failure to find the genes for TS using linkage analysis, (e) the brain imaging studies showing hypometabolism of the frontal lobes, (f) the relationship between dopamine D2 receptor density and regional blood flow, (g) the correlation between tics and dopamine D2 receptor density in TS, (h) the motor hyperactivity of dopamine transporter and dopamine D3 receptor gene knockout mice, (i) the LeMoal and Shaywitz dopamine deficiency animal models of ADHD, (j) the NE models of ADHD, (k) the failure to explain ADHD on the basis of any single neurotransmitter defect, (l) the response of ADHD to dopamine and alpha 2-adrenergic agonists, (m) the small percentage of the variance of specific behaviors accounted for by each gene, and numerous other aspects of ADHD. The implications of the polygenic model for the understanding, diagnosis and treatment of ADHD and TS, as well as other psychiatric disorders, are reviewed.
152 citations
TL;DR: A brief review of empiric studies on habit reversal training is provided, to update readers on the current state and future of behavior therapy for Tourette syndrome, and provide resources for those readers interested in additional information.
Abstract: It is well established that Tourette syndrome has a neurobiologic origin. Although pharmacotherapy is the most commonly prescribed intervention, there is considerable evidence to support the use of behavior therapy, specifically habit reversal training, as an alternative or adjunct treatment for some individuals with Tourette syndrome. Unfortunately, many professionals are unfamiliar with habit reversal training. The purpose of this review is to provide readers with a brief review of empiric studies on habit reversal training, update readers on the current state and future of behavior therapy for Tourette syndrome, and provide resources for those readers interested in additional information.
TL;DR: The comorbidity between TS and ADHD is discussed and treatment suggestions are offered, including atomoxetine, which although not documented widely in the setting of tics and TS, may prove useful in this setting; further research is required.
Abstract: Tourette's Syndrome (TS) is now recognised to be a common childhood onset neurodevelopmental disorder. Attention deficit hyperactivity disorder (ADHD) is also a common childhood disorder. There are many cases in which the two disorders are comorbid. The reasons for this are unclear, but the comorbidity does not necessarily point to one genetic cause. Sleep is also often disturbed in individuals with TS and ADHD. The treatment implications of ADHD in the setting of tics or TS are important. Clonidine is suggested as a first line treatment. It was once thought that stimulants were contraindicated in the treatment of ADHD in the setting of TS, whereas it is suggested that they may be safe, but should be used judiciously. In addition, it was once thought that the combination of stimulants and clonidine was contraindicated, but from a large study the combination does appear to be safe. A relatively new medication for ADHD is atomoxetine, and although not documented widely in the setting of tics and TS, it may prove useful in this setting; further research is required. This commentary briefly discusses the comorbidity between TS and ADHD and offers treatment suggestions.
TL;DR: The neural circuits and neurochemistry of Tourette syndrome are reviewed and the evidence for and against a role for autoimmunity in the expression of tics is evaluated.
Abstract: The neuroanatomy and neurochemistry underlying tic disorders are thought to involve corticostriatothalamocortical circuits and dysregulation of their component neurotransmitter systems. Tourette syndrome is a tic disorder that begins in childhood and follows a waxing and waning course of tic severity. Although it is generally believed to have a genetic component, its etiology has not been fully elucidated. The clinical entity pediatric autoimmune neuropsychiatric disorders associated with streptococcal infection (PANDAS) has led some to suggest that the pathophysiology of tics in some individuals might involve a postinfectious autoimmune component. We review the neural circuits and neurochemistry of Tourette syndrome and evaluate the evidence for and against a role for autoimmunity in the expression of tics.
TL;DR: The current study showed that working memory, inhibition, and response variability, are distinct, but related cognitive domains in children with developmental psychopathologies.
TL;DR: The findings of a reduced interhemispheral white matter connectivity add to the understanding of neural connectivity and plasticity in the brains of children who have Tourette syndrome.
Abstract: Background Brain imaging studies have revealed anatomical anomalies in the brains of individuals with Tourette syndrome (TS). Prefrontal regions have been found to be larger and the corpus callosum (CC) area smaller in children and young adults with TS compared with healthy control subjects, and these anatomical features have been understood to reflect neural plasticity that helps to attenuate the severity of tics. Method CC white matter connectivity, as measured by the Fractional Anisotropy (FA) index from diffusion tensor images, was assessed in 20 clinically well-defined boys with Tourette syndrome and 20 age- and gender-matched controls. Results The hypothesis that children with TS would show reduced measures of connectivity in CC fibers was confirmed for all subregions of the CC. There was no significant interaction of TS and region. Reductions in FA in CC regions may reflect either fewer interhemispheric fibers or reduced axonal myelination. FA values did not correlate significantly with the severity of tic symptoms. Group differences in measures of connectivity did not seem to be attributable to the presence of comorbid ADHD or OCD, to medication exposure, or group differences in IQ. Conclusion Our findings of a reduced interhemispheral white matter connectivity add to the understanding of neural connectivity and plasticity in the brains of children who have TS.
TL;DR: There are qualitative and quantitative differences in the phenotypic expression of tic disorders in OCD patients, depending on whether the subject has TS or only CMVT.
Journal Article•
TL;DR: Results do not support the hypothesis that PANDAS and Tourette syndrome are secondary to antineuronal antibodies, and longitudinal studies are required to determine whether autoantibodies correlate with fluctuations in clinical activity.
TL;DR: Achieving the most effective treatment of a child with tics is contingent on proper diagnosis of the movement disorder and thorough assessment for other problems, followed by consideration of both nonpharmacologic and pharmacologic interventions for any and all symptoms interfering with the child's function and quality of life.
Abstract: Tics, patterned movements distinct from stereotypies, myoclonus, and other hyperkinetic movements, are quite common in children, particularly among those with developmental and psychiatric disorders. Thus, tics can indicate the presence of atypical neurodevelopment or broader difficulties with cognition or mood. Tics are also the cardinal feature of Tourette syndrome, a childhood-onset neurobehavioral disorder characterized by a chronic inability to suppress or an urge to perform patterned, repetitive movements. Patients with Tourette syndrome most commonly have, in addition to tics, symptoms of inattention, hyperactivity, obsessiveness, or anxiety. Achieving the most effective treatment of a child with tics is contingent on proper diagnosis of the movement disorder and thorough assessment for other problems, followed by consideration of both nonpharmacologic and pharmacologic interventions for any and all symptoms interfering with the child's function and quality of life. This review focuses primarily on the diagnosis and medical treatment of tics in children and adolescents with Tourette syndrome.
TL;DR: It is crucial for clinicians to be familiar with co-occurring disorders because they are often more impairing than tics and can influence the initial treatment choice when tic symptoms are present.
Abstract: More than half of all children and adolescents with Tourette syndrome show evidence of psychiatric comorbidity, exhibiting symptoms of attention-deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder, and other anxiety and mood disorders. Although the prevalence of co-occurring conditions varies depending on the clinical setting, it is crucial for clinicians to be familiar with these disorders because they are often more impairing than tics and can influence the initial treatment choice. Left untreated, these conditions can negatively affect important developmental outcomes, such as academic and social functioning. We review the most common co-occurring disorders, the relationship of these co-occurring disorders to Tourette syndrome, and treatment recommendations for co-occurring conditions when tic symptoms are present.
TL;DR: These cases illustrate that a new neuroleptic, aripiprazole, may be an effective treatment for the motor and vocal tics of Tourette Syndrome (TS), even in younger people.
Abstract: Objective These cases illustrate that a new neuroleptic, aripiprazole, may be an effective treatment for the motor and vocal tics of Tourette Syndrome (TS), even in younger people. Method A case series of 11 consecutive patients with TS (age range 7–50 years; M ¼ 7) who were felt to require neuroleptic medication, were treated with aripiprazole, the majority of whom had been refractory to treatment with other neuroleptics, and in one case, Habit Reversal Training as well. Results Ten out of the 11 patients who were treated with aripiprazole improved, although to differing degrees. The only individual who showed no response was treated for only 1 month with a low dose (5 mg). Eight of the patients had been treated with many typical and atypical neuroleptics without success, and which had also given unacceptable side effects, resulting in them being unable to function at times. One was also unresponsive to previous Habit Reversal Training. The response to aripiprazole was dramatic and quick in five patients; in the rest (5/10) the response was less dramatic. In the majority of patients, response was sustained. The successful aripiprazole doses were between 10–20 mg daily. Side effects were mild and transient. This, to the best of our knowledge, is the first case series of patients with TS successfully treated with aripiprazole in the United Kingdom, and one of the few to date in the English Scientific literature. Our patients are also the first cases reported, in which the patients were assessed and whose improvement was monitored using standardised schedules and rating scales, such as the Yale Global Tic Severity Rating Scale and MOVES. Aripiprazole was licensed for use in patients with schizophrenia in the European Union in June 2004. We discuss possible reasons for these dramatic and idiosyncratic responses to aripiprazole. Conclusion We suggest that aripiprazole may well be useful for individuals with TS as response to it is often quick, dramatic, sustained and with few generally mild and transient side effects. Copyright # 2006 John Wiley & Sons, Ltd.
TL;DR: This unbiased analysis confirmed an association between striatal abnormalities and Tourette syndrome, and the hippocampal volume alterations indicate an involvement of temporolimbic pathways of the CSTC in the syndrome.
Abstract: The genesis of Tourette syndrome is still unknown, but a core role for the pathways of cortico-striatal-thalamic-cortical circuitry (CSTC) is supposed. Volume-rendering magnetic resonance imaging data-sets were analysed in 14 boys with Tourette syndrome and 15 age-matched controls using optimised voxel-based morphometry. Locally increased grey-matter volumes (corrected P < 0.001) were found bilaterally in the ventral putamen. Regional decreases in grey matter were observed in the left hippocampal gyrus. This unbiased analysis confirmed an association between striatal abnormalities and Tourette syndrome, and the hippocampal volume alterations indicate an involvement of temporolimbic pathways of the CSTC in the syndrome.
TL;DR: D2 receptor availability was significantly lower in the orbitofrontal cortex, primary motor cortex, anterior cingulate gyrus, mediodorsal nucleus of thalamus, and hippocampus, areas important for motivation and reward, sensory gating, movement, and attention.
Abstract: We used [F-18]fallypride PET in six adults with Tourette syndrome and age-matched controls to assess extrastriatal dopamine 2 (D2) receptors. D2 receptor availability was significantly lower in the orbitofrontal cortex, primary motor cortex, anterior cingulate gyrus, mediodorsal nucleus of thalamus, and hippocampus, areas important for motivation and reward, sensory gating, movement, and attention. Altered dopaminergic function in mesolimbocortical systems and thalamus may contribute to increased motivational salience of tics.
TL;DR: In the neurocognitive domain, the TD+ADHD comorbidity can be identified as a unique nosologic entity and both the spontaneous theta activity and late event-related theta oscillations appear as neurophysiological markers of the ADHD condition.
TL;DR: The management of Tourette Syndrome is often complicated by the presence of attention–deficit/hyperactivity disorder, obsessivecompulsive disorder, and other behaviour disorders, and a multimodal treatment is usually indicated.
Abstract: Tic disorders are stereotypic behaviours,more frequent than once believed, and therefore likely to be encountered by primary care physicians. Tics usually begin in childhood and are the clinical hallmark of Tourette Syndrome (TS), the most common cause of tics. TS is a relatively common neurobehavioural disorder with a spectrum of manifestations that wax and wane during its natural course. The pathophysiology of tics, at molecular and cellular level, is still unknown,whereas structural and functional neuroimaging studies have shown the involvement of the basal ganglia and related cortico–striato–thalamo–cortical circuits, and the dopaminergic neuronal system. Moreover, TS has a strong genetic background. The management of TS is often complicated by the presence of attention–deficit/hyperactivity disorder, obsessivecompulsive disorder, and other behaviour disorders. The correct diagnosis is a fundamental step for a proper management of these disorders, and a multimodal treatment is usually indicated. This approach includes educational and supportive interventions, as well as pharmacological treatments when tics are at their worst.
TL;DR: To investigate cerebral structure in Tourette's syndrome (TS), an attempt is made to establish a haemorrhage-like lesion on the outside of the orbiculares of the brain in the form of an X-ray image.
Abstract: Objective
To investigate cerebral structure in Tourette's syndrome (TS).
Methods
Voxel-based morphometry study of high-resolution MRIs in 31 TS patients compared with 31 controls.
Results
Increased gray matter mainly in the left mesencephalon in 31 TS patients.
Interpretation
This result constitutes strong and direct evidence supporting Devinsky's hypothesis (Devinsky O. Neuroanatomy of Gilles de la Tourette's syndrome. Possible midbrain involvement. Arch Neurol 1983;40:508–514) according to which midbrain disturbances play an important pathogenic role in TS. Ann Neurol 2006;59:381–385
TL;DR: This review summarizes this complex and rapidly evolving area of clinical research into PANDAS, a well-defined syndrome in which tics and/or obsessive-compulsive disorder consistently exacerbate in temporal correlation to a group A β-hemolytic streptococcal infection.
Abstract: Streptococcal infection in children is usually benign and self-limited. In a small percentage of children, prominent neurologic and/or psychiatric sequelae can occur. Sydenham chorea is the best defined and best recognized. PANDAS (pediatric autoimmune neuropsychiatric disorders associated with streptococcal infection) is a well-defined syndrome in which tics (motor and/or vocal) and/or obsessive-compulsive disorder consistently exacerbate in temporal correlation to a group A beta-hemolytic streptococcal infection. PANDAS constitutes a subset of children with tics, Tourette syndrome, and obsessive-compulsive disorder. In addition to strictly defined PANDAS, we and others have recognized several PANDAS variants, including adult-onset variant, a dystonic variant, a myoclonic variant, and a "chronic" PANDAS variant. The nosology and classification of these entities are rapidly evolving. The recognition that some pediatric neurobehavioral syndromes have infectious and/or immunologic triggers points to important new avenues of disease treatment. In this review, we summarize this complex and rapidly evolving area of clinical research.
TL;DR: The clinical evaluation of patients and family members in a large Dutch Gilles de la Tourette Syndrome pedigree and the decisions encountered with respect to phenotyping are described and an accurate definition of the Tourette phenotype is discussed.
Abstract: Gilles de la Tourette syndrome is a complex neuropsychiatric disorder, which becomes evident in childhood between the ages of 2 and 15 years. Tourette syndrome is defined by the occurrence of a large range and variable number of unwanted repetitive simple or complex motor and vocal tics that start in childhood and follow a waxing and waning course. A major gene for this syndrome has not yet been identified, probably owing to both genetic and phenotypic heterogeneity of this disease. This article describes the clinical evaluation of patients and family members in a large Dutch Gilles de la Tourette Syndrome pedigree and the decisions encountered with respect to phenotyping. The importance of an accurate definition of the Tourette phenotype is discussed, which is highly important for reliable genetic linkage and association studies. Subsequent linkage analysis resulted in three linkage peaks on different chromosomes 3q, 9q, and 13q. Multipoint analysis resulted in a single linkage peak with logarithm of odds score 2.55 with marker D3S1311 on chromosome 3q.
TL;DR: The findings showed the TS group to perform more poorly on one test involving behavioral inhibition, but did not provide strong support for an interpretation based solely on inhibitory deficits, and provided further evidence that uncomplicated TS is associated with only mild, circumscribed impairment.
Abstract: Tourette's syndrome (TS) is a neurodevelopmental disorder associated with frontostriatal dysfunction. The extent of any cognitive impairment associated with uncomplicated TS is unclear, as comorbid psychiatric symptomatology is thought to contribute to cognitive deficits. Previous studies have found evidence of mild performance deficits, most commonly on tasks that involve inhibitory processes. The present study evaluated this in carefully screened adult participants with TS. The findings showed the TS group to perform more poorly on one test involving behavioral inhibition (sentence completion), but did not provide strong support for an interpretation based solely on inhibitory deficits, and there was no evidence of impairment on another behavioral inhibition task (flanker test). There were also no differences between the groups on tasks involving working memory (n-back), task switching, or object alternation learning. The findings provide further evidence that uncomplicated TS is associated with only mild, circumscribed impairment. The nature of any impairment is discussed.
TL;DR: Deep brain stimulation of targets in both thalamus1 and globus pallidus interna (GPi)2 has been used successfully to control tics in severe cases of Tourette syndrome and following placement of bilateral GPi stimulators, this 26-year-old-right handed man with Tourette's syndrome is shown to have normal tics.
Abstract: Deep brain stimulation of targets in both thalamus1 and globus pallidus interna (GPi)2 has been used successfully to control tics in severe cases of Tourette syndrome. Following placement of bilateral GPi stimulators, this 26-year-old-right handed man with …
TL;DR: The key epidemiologic, linkage, and association studies in Tourette syndrome are described and the strategies currently being used to identify Tourette Syndrome susceptibility genes are illustrated.
Abstract: Although the genetic basis of Tourette syndrome is well established, uncertainty about how best to define and assess the Tourette syndrome phenotype has hampered efforts to identify the genes responsible for susceptibility to the disorder. In addition, such efforts have typically been underpowered or were undertaken before the technology was available to perform systematic genome-wide genetic investigations. The Tourette Syndrome Association International Consortium on Genetics was formed by more than a dozen research groups from around the world to develop common approaches to phenotyping Tourette syndrome and to pool samples for uniform, well-powered genetic investigations. Several recent advances, including the completion of genome-wide scans of affected sib-pairs and large families, show real promise for identifying Tourette syndrome susceptibility genes. In this review, we describe the key epidemiologic, linkage, and association studies in Tourette syndrome and illustrate the strategies currently being used to identify Tourette syndrome genes.