Auditory evoked potentials in Gilles de la Tourette syndrome

Gilles de la Tourette syndrome (TS) has been increasingly studied neurophysiologically as well as clinically. Obsessive-compulsive disorder (OCD) and attention deficit disorder (ADD) have been recognized to be part of the continuum of TS. We recorded brainstem auditory evoked potentials (BAEPs) and long-latency auditory event-related potentials (ERPs) in 20 patients with TS, 10 of whom had ADD and 6 OCD. TS patients with and without OCD and ADD did not differ in BAEP latencies, and no differences were found from normal controls. AEP latencies did not differ between TS patients and controls. TS patients with ADD had longer N100 and N200 latencies than TS patients without ADD, and TS patients with OCD had shorter N200 and P300 latencies. These findings suggest that TS is neurophysiologically heterogenous, and that TS patients with OCD or ADD may differ from those without.

Menstrual cycle-related fluctuations of tics in Tourette syndrome

In a survey of 47 women of all ages with Tourette syndrome, 26% had a premenstrual increase in tics (P less than .001) when various hormonal states were examined. An increase in tics at menarche predicted the premenstrual tic exacerbation (P less than .001). In contrast, other hormonally influenced conditions, such as premenstrual syndrome, oral contraceptive use, pregnancy, and menopause were not associated with a change in tic frequency. The finding of an increase in tic frequency during the estrogenic phase of the menstrual cycle provides additional insight into an important control mechanism for tic expression and suggests possible therapeutic options.

Relevance of the habenular complex to neuropsychiatry: a review and hypothesis

Since the initial observation by Brown (1914) that electrical stimulation applied to the habenular efferent bundle in the chimpanzee evoked a pattern of respiration which closely resembled the act of laughter, the habenular complex has remained a mysterious structure. The anatomy of the habenular complex is well delineated (Jones, 1985) forming a major component of the dorsal diencephalic conduction system. Data derived mainly from animal experimentation over the past decade point to the fact that the habenular complex functions as an important link between the limbic forebrain and the midbrain-extrapyramidal motor system. The elucidation of the functions of the habenular complex may thus significantly increase the current insight into the understanding of the interaction between behavioral and motor functions. Clearly, such information would be of great relevance for further understanding of neuropsychiatric disorders such as schizophrenia, Parkinson's disease, Tardive dyskinesia, and Tourette's syndrome in which behavioral and motor impairments are interfaced. This review summarizes anatomical, functional, and pharmacological aspects of the habenular complex and discusses its potential contribution to the pathophysiology of selected neuropsychiatric and movement disorders.

Exacerbation of Gilles de la Tourette's syndrome associated with thermal stress: a family study

Gilles de la Tourette's syndrome (TS) is a familial disorder that is often exacerbated by stress or fatigue. Here we present a family of a TS proband that has several members with obsessive-compulsive symptoms, a bleeding disorder, and an unusual sensitivity to heat. The proband, who is affected by all of these traits, was challenged with heat or exercise in climate-controlled conditions and showed a marked increase in the frequency of tics.

Reflex tics in two patients with Gilles de la Tourette syndrome

Two patients with Gilles de la Tourette syndrome (GTS) showed tics triggered by external stimuli. This unusual feature is of significance to the aetiology of GTS and in particular the relationship between GTS and the startle response.

Anomalous kinetic visual fields found in family members of patients with a confirmed diagnosis of Gilles de la Tourette syndrome

Three visual manifestations of Gilles de la Tourette syndrome (TS), a neuropsychiatric disorder, have been previously reported. In this paper we report anomalies in the measured kinetic paracentral visual field of TS patients and their family members. We found that 96% of TS patients exhibited paracentral kinetic visual field defects (nasal and temporal steps, enlargement, "ringing," and/or baring of the blind spot). Ninety-three percent of fathers of TS children and, surprisingly, about 80% of mothers exhibit these characteristic visual field anomalies. Sample data and examples of family studies are reported.

Computerized EEG frequency analysis in Gilles de la Tourette syndrome

EEG abnormality has been reported in Gilles de la Tourette Syndrome but not confirmed in later studies. We carried out computerized EEG frequency analysis in 30 patients with the disorder, using Nicolet Pathfinder II frequency analysis software, versions 1.2 and 3.1 EEG was recorded from 01-A1+A2, 02-A1+A2, Fz-A1+A2, F7-C3, F8-C4, T5-01, and T6-02 in Tourette Syndrome patients and controls. Controls were taking no medications, and drug therapy for Tourette Syndrome had been stopped or not yet initiated in the patient group. Modal alpha frequency (MAF), maximal alpha frequency (MxAF), and spectral edge frequency (SEF) was measured in occipital and frontal derivations in 24 patients and controls. Left frontal (MOLF) and right frontal (MORF) mobility was calculated in F7-C3 and F8-C4 in 21 patients and controls. No significant differences were found between Tourette Syndrome patients and controls by two-tailed t-test. These findings are in accord with recent evidence of little or no EEG abnormality in Tourette Syndrome patients as compared to normals.

Deranged modulatory midbrain opioid and gonadotrophin functions: relevance to Tourette's syndrome

In the following communication we discuss evidence suggesting that an abnormal opioid-gonadotrophin interaction at the midbrain may be essential to the clinical expression of vocal tics in Tourette's Syndrome (TS). Data derived from animal studies and the striking similarity between the symptomatology of TS and encephalitis lethargica (EL) add further support to our hypothesis implicating an abnormal opioid-gonadotrophin interaction in the pathophysiology of TS.

The coexistence of tics and dystonia

We studied nine patients with motor and phonic tics and other features of Tourette's syndrome, who developed persistent dystonia in addition to their tics. All, except one, were males (mean age, 35.8 years; range, 8 to 59 years), and had onset of tics prior to age 18 years (mean age, 9 years; range, 1.5 to 17 years). None of the patients were treated with neuroleptic drugs prior to the onset of dystonia. Torticollis and blepharospasm were the most common forms of dystonia. Seven patients had a history of tics in first degree relatives. While these patients were seen in a specialized movement disorder clinic and may, therefore, represent a population with atypical and more severe symptoms, the high prevalence rate of dystonia (5.0% of all patients with Tourette's syndrome seen in the clinic) suggests that some patients with tics may have an increased risk for dystonia.

Prolactin in childhood obsessive-compulsive disorder: clinical correlates and response to clomipramine

Basal prolactin concentrations were measured before treatment in 18 children and adolescents with obsessive-compulsive disorder as well as in 15 of these patients after 4 and 8 weeks of clomipramine treatment. Basal prolactin levels were influenced by a history of chronic tic disorder and by the duration and severity of obsessive-compulsive symptoms. Clomipramine administration significantly increased basal prolactin levels. A slight decline in prolactin levels during the last 4 weeks of clomipramine treatment was positively correlated with a favorable treatment response and negatively correlated with duration of illness. If the changes in prolactin levels observed during clomipramine treatment are due primarily to changes in serotonergic neurotransmission, these data suggest that clomipramine treatment of obsessive-compulsive disorder produces an adaptive decrease in the responsiveness of serotonergic receptors.

Tourette syndrome attributed to frontal lobe dysfunction: numerous etiologies involved

The etiology of Tourette Syndrome (TS) according to prevailing views is unknown; there is evidence for both familial and sporadic cases. The author theorizes that abnormal discharges in the frontal lobes comprise the "final common dysfunction" that results in numerous phenomena labelled Tourette syndrome. Facial, vocal, and other motor symptoms of TS are catalogued in parallel with facial, vocal, and body movements that occur during frontal lobe seizures. The variety of etiologies that cause frontal lobe seizures--when applied to TS--can account more readily for heterogeneity of clinical presentations, the numerous "dual diagnosis" cases, and differential response to medication than can a single-gene theory.

The effect of sleep on the dyskinetic movements of Parkinson's disease, Gilles de la Tourette syndrome, Huntington's disease, and torsion dystonia

The effect of sleep on the involuntary movements or dyskinesias in Parkinson's disease, Huntington's disease, primary and secondary torsion dystonia, and Gilles de la Tourette syndrome was studied in a total of 52 patients and 10 normal subjects using video electroencephalographic telemetry. Movements typical of the wake pattern were seen occasionally during unequivocal sleep in all but two completed studies, and in each condition reappeared under similar circumstances. The movements were most likely to occur after awakenings or lightenings of sleep, or in stage one sleep. The movements were very rare during the deeper phases of sleep. Those movements that occurred during sleep without awakenings were usually preceded by arousal phenomena and, rarely, by sleep spindles or slow waves. The control group showed normal "semipurposeful" movements under the same conditions during sleep. The rare appearance of the different dyskinesias and normal movements under similar circumstances during sleep could be a result of common effects on the generator systems or changes in the excitability of the final common motor pathway.

Dystonic tics in patients with Tourette's syndrome

Dystonic tics, in contrast to clonic tics, are relatively slow and temporarily sustained twisting, pulling, or squeezing movements producing briefly maintained abnormal postures. Because dystonic tics often present diagnostic difficulties, we studied these motor tics in 156 patients with Tourette's syndrome (TS). In addition to clonic motor and vocal/phonic tics, seen in all patients, 89 (57%) of them exhibited one or more dystonic tics. The most common dystonic tics were oculogyric deviations (43 patients), blepharospasm (23), and dystonic neck movements (11). Blinking (110) and facial twitching (86) were the most common clonic tics. Except for possibly a greater familial occurrence, a higher frequency of previous head trauma, and associated attention deficit disorder, the group of patients with dystonic tics did not significantly differ in any of the major clinical variables from those TS patients without dystonic tics. We conclude that dystonic tics are typical motor manifestations of TS and that patients with these motor tics are not different from those with more typical clonic tics.

Tourette syndrome and other tic disorders. Diagnosis, pathophysiology, and treatment

In this report, we discuss the definition, characteristics, pathophysiology, and treatment of tic disorders with a major emphasis on Tourette syndrome. Although the diagnosis of a tic disorder depends on the presence of motor and/or phonic tic(s), patients with these problems also have a variety of co-morbid features including obsessive-compulsive symptoms, attention-deficit hyperactivity disorder, behavioral difficulties, and learning disabilities. Conservative estimates for Tourette syndrome suggest a prevalence rate of 0.1-1.0 per 1000. This syndrome is inherited in a sex-influenced autosomal dominant pattern with either chronic multiple tic disorder or obsessive-compulsive disorder as alternative phenotypes of the putative gene. Current evidence continues to support a pathophysiologic mechanism involving synaptic neurotransmission, with the dopaminergic system as a primary candidate. Therapeutically, it is essential to clarify whether a patient's problems are related to tics or associated behavioral difficulties. Pharmacotherapy for motor and phonic tics is strictly symptomatic and should be reserved for those with functionally disabling symptoms. A comprehensive individualized treatment program is often required in the care of individuals with tic disorders.

Neuropsychological correlates of obsessive characteristics in Tourette syndrome

The relationship between obsessive-compulsive (OC) characteristics and performance on a test sensitive to frontal lobe function (Wisconsin Card Sorting Test) was examined in a sample of 100 patients between the ages of 6 and 18 years. All patients met DSM-III-R criteria for Tourette syndrome (TS), confirmed by a neurologist or psychiatrist. Performance on the Wisconsin Card Sorting Test was correlated with ratings of OC characteristics, but not with other TS symptoms. This relationship was maintained even when Full-Scale IQ and the total number of Tourette symptoms were controlled. The effect could not be attributed to medication. These findings were interpreted in the context of models of basal ganglia-cortical associations. It was speculated that different symptoms associated with TS may have different neuroanatomic substrates.

Dopamine and myopia

Dopamine may play a role in form-deprivation myopia in chickens. Anomalies of the dopaminergic system are believed to be responsible for manifestations of symptoms in Tourette Syndrome (TS), a neuropsychiatric disorder. Visual anomalies have been identified in TS. In this paper, refractive error in people suffering from TS is compared with available population studies. Refractive errors in TS are found to be similar to those in the normal population.

Routine and quantitative EEG analysis in Gilles de la Tourette's syndrome

Gilles de la Tourette's syndrome (GdlT) is a neurobehavioral disorder, with a reportedly high frequency of EEG abnormalities. We performed EEGs on 48 consecutive patients with GdlT, and frequency analysis in 26 patients (17 males), and compared the results with those from age- and sex-matched normal controls. Routine 18-channel EEG revealed minimal diffuse nonspecific slowing in only 3 of 48 patients (6%) and in 2 of 26 controls (7.7%). The frequency analysis of the EEG of the 26 GdlT patients and their normal controls showed similar brain activity. We conclude that no significant differences exist between the EEG activity in GdlT patients as compared with that in sex- and age-matched controls in routine as well as in quantitative EEG.

Untying the gordian knot: the genetics of Tourette syndrome

A review of the current status of the genetics of Tourette syndrome is presented. Over the course of the 104 years since Gilles de la Tourette described the syndrome that bears his name, a body of carefully collected, described, and analyzed data has produced a model of the genetics that implicates a single dominant gene that is variably penetrant in males and females. Moreover, the locus of action of this gene is most likely in the dopaminergic system of the midbrain. A systematic search for this gene using recombinant DNA techniques is under way.

Beyond the serotonin hypothesis: a role for dopamine in some forms of obsessive compulsive disorder?

It seems unlikely that a solitary disturbance in serotonin function can fully account for the pathophysiology of obsessive compulsive disorder. The authors propose that some forms of obsessive compulsive disorder, e.g., obsessive compulsive disorder with a history of Tourette's syndrome, may involve a relative or absolute derangement in both brain serotoninergic and dopaminergic systems. A role for dopamine in the pathophysiology of obsessive compulsive disorder is supported by a review of the preclinical and clinical evidence. Additional studies are needed to more directly evaluate dopamine function in patients with obsessive compulsive disorder.

Gilles de La Tourette's syndrome and some forms of obsessive-compulsive disorder may share a common genetic diathesis

Family aggregation and twin studies suggest that Gilles de La Tourette's syndrome (TS) and some forms of obsessive-compulsive disorder (OCD) are etiologically related. Neuroanatomically, the structures of the basal ganglia, thalamus and cortex have also been implicated in both TS and OCD suggesting a common neural substrate for these disorders. Neurochemical and neuropharmacological studies have provided less compelling data concerning this heuristically important association. Clinical studies have largely focused on the role of the nigrostriatal, mesolimbic and mesocortical dopaminergic systems in the pathophysiology of TS. In the case of OCD, serotoninergic systems originating in the raphe nuclei and projecting rostrally, have received considerable attention. Recent neuropathological studies of TS have implicated the endogenous opioid peptide, dynorphin, in the pathophysiology of TS. Animal studies have shown that dynorphin can modulate both dopaminergic and serotonergic systems. We have undertaken a cerebrospinal fluid (CSF) study to determine if abnormalities in dynorphin A concentration can be observed in drug-free TS and OCD patients. Preliminary results from this study suggest: 1) that TS patients have an elevated level of CSF dynorphin A (1-8) compared to normal controls; 2) that their level of CSF dynorphin is correlated with the severity of their OCD symptoms; 3) that some, but not all, OCD patients also have high levels of this neuropeptide in their CSF.

Cocaine-associated multifocal tics

Of 4 patients with cocaine-induced multifocal tics, 2 had Tourette's syndrome and had a severe exacerbation of their symptoms. One of these 2 patients experienced the exacerbation following her 1st exposure to the drug; the 2nd, a habitual cocaine snorter, after smoking "crack" for the 1st time. The other 2 patients were habitual cocaine abusers who, following a binge with high doses of cocaine, experienced new-onset tics.

Perinatal factors in the expression of Tourette's syndrome: an exploratory study

The search for nongenetic factors that mediate the expression of a genetic vulnerability to Tourette's syndrome (TS) is an important undertaking that may provide valuable clues concerning the pathophysiology of this disorder as well as potential treatment approaches. In a direct interview study, the perinatal experiences of 31 TS patients were compiled in an effort to identify risk factors associated with tic severity. Severity of maternal life stress during pregnancy, gender of the child, and severe nausea and/or vomiting during the first trimester were found to be significantly associated with current tic severity. Future longitudinal studies of "at-risk" children are needed to confirm these findings. Set in the context of a known chromosomal site for the TS diathesis, such studies will permit the identification and quantification of risk and protective factors in the expression of TS and further develop TS as a model neuropsychiatric disorder for the study of gene-environment interactions.

Brain imaging as a tool in establishing a theory of brain pathology in obsessive compulsive disorder

Positron emission tomography (PET) studies using 18F-2-deoxy-2-fluoro-D-glucose (FDG) to determine glucose metabolic rates have been used recently to correlate the symptoms of obsessive compulsive disorder (OCD) with neuroanatomically localized brain dysfunctions. These studies, as well as data from other techniques and other disease states, suggest that the orbital cortex and the striatum are dysfunctional in OCD. This information can be used to construct a theory of how the symptoms of OCD and the related Gilles de la Tourette's syndrome and chronic motor tics are mediated by the central nervous system.

The effect of nocturnal physiological sleep on various movement disorders

Thirty-one subjects affected by different movement disorders underwent polygraphic and videotape monitoring during nocturnal sleep, to assess movement patterns during the night. It was possible to distinguish two categories of disorders according to their pattern of movements. In the largest group (Meige's syndrome, blepharospasm, amyotrophic choreoacanthocytosis, Tourette syndrome, tonic foot, hemiballism) abnormal movements were still present during sleep, but decreased in frequency and amplitude in all stages. The second group presented three syndromes (nocturnal paroxysmal dystonia, nocturnal myoclonus, restless legs syndrome), in which light non-rapid-eye-movement sleep induced a strong activation of abnormal movements, whereas rapid-eye-movement sleep suppressed them.

Gilles de la Tourette's syndrome in twins: clinical and neurochemical data

A pair of identical twins (probability of monozygosity by genetic marking = 99.99%) with Gilles de la Tourette's syndrome (GTS) were studied clinically and neurochemically. The two boys were distinguished within the family by dramatic differences in their behavior and tics. Twin 1 had severe motor tics, loud vocalizations, coprolalia, and school behavior problems, whereas twin 2 was only mildly affected. Neither boy had ever been treated with medication for his tic disorder. Lumbar puncture was performed on each after a night of bed rest. In spite of the marked clinical differences between the two boys, the major indices of dopamine and serotonin turnover in the cerebrospinal fluid were equivalent. Homovanillic acid levels were 65 and 60 ng/ml, respectively, and 5-hydroxyindoleacetic acid levels were 36 and 39 ng/ml. Observation of these twins suggests that the phenotypic expression of GTS relates to more factors than inheritance. Neurochemical metabolites of dopamine and serotonin did not reflect the comparative clinical severity of GTS in these boys.

Technical and clinical aspects of topographic brain mapping

TBM provides physiological and diagnostic information which is quite complementary to EEG, but does not replace the need for standard EEG recordings. For example, it does not show subtle morphologic abnormalities such as FIRDA, PLEDs or epileptiform discharges. Simultaneous EEG recording as well as impeccable technique are essential in proper recording of TBM, particularly as it can generate new forms of artifact. By prolonging the averaging time to over 180 seconds, and by application of flexible montages, a more accurate and cleaner record with less artifact can be obtained. Certain phenomena such as "centrifugal effect" and "comet effect" are examples of new problems generated by the advent of TBM. On the other hand, TBM can demonstrate subtle asymmetries, lateralization and localization effects more efficiently than a standard EEG. TBM is quite helpful clinically, when recording is done properly from a technical standpoint, in the diagnosis of post-traumatic syndrome and post-traumatic seizure disorder. It demonstrates subtle focal and lateralized asymmetries in cerebral hemispheric frequency bands in such patients. This information helps differentiate neurologic complications from psychiatric disorders. TBM plays a useful role in the differentiation and management of various other disorders, including depression, behavioral disturbances and dementias.

Visual field defects detected in patients with Gilles de la Tourette syndrome: preliminary report

The presence of visual field anomalies was measured using Goldmann kinetic perimetry in twelve patients, age 7 to 39 with Gilles de la Tourette syndrome. Refraction to the cupola was carefully controlled. The visual acuity of the group was good to excellent. Visual field alterations were prechiasmal, generally non-symmetric, and best described as arcuate defects, steps, baring of the blind spot and enlargement of the blind spot. Central fields were most commonly affected, i.e., I/2e to I/1B isopters. There was no evidence of glaucoma in any of the patients although two patients exhibited keratoconus and another one manifested moderate to high astigmatism. Visual involvement other than ocular and lid tics have not been reported in Tourette syndrome. This research represents clear evidence of additional physical components in this condition. Automated visual field measurements are not recommended in this population because of the presence of non-predictable tic and vocal behavior (both may result in head/eye movements). Suppression of tic behavior can be very fatiguing. (Eight of twelve of the patients reported exhibited signs of marked fatigue during testing.)

Abnormalities of the blink reflex in Gilles de la Tourette syndrome

The blink reflex and it's recovery cycle were studied in 26 patients with Gilles de la Tourette syndrome and 10 controls. There was a significant increase in the mean duration of the R2 response. The amplitude of the R2 response following paired shocks (mean R2[T]/R2[C]%) was 11%, 40% and 52% of the conditioning stimulus with intervals of 200 ms, 500 ms and 1 second in the patients, compared with 10%, 17% and 32% respectively in the controls. Half the patients, however, had normal recovery cycles and voluntary suppression of tics and blinks reduced the amplitude of R2 in all patients. These results suggest increased excitability of brainstem interneurons in Gilles de la Tourette syndrome.

Recurrence of complex motor and vocal tics in an elderly woman responsive to opiates

A 73-year-old woman experienced recurrence of complex and motor tics in late adult life. Involuntary vocalizations that had a cough-like quality constituted the most distressing feature of her tick disorder. The latter was unresponsive to diverse pharmacological agents including neuroleptics, clonazepam, baclofen, phenytoin, and various nonnarcotic antitussive agents. Low dose oxycodone produced almost complete abolishment of the cough-like involuntary vocalizations. This report implicates derangement in the activity of the endogenous opioid system in the pathophysiology of Tourette's syndrome, and suggest that opiates may be prescribed in the therapy of TS patients otherwise recalcitrant to administration of haloperidol or other dopamine blocking agents.

[Gilles de la Tourette syndrome associated with epileptiform discharges: report of three cases]

This report presents the clinical observation of 3 cases of Gilles de la Tourette Syndrome (GTS) with epileptiform discharge of electroencephalogram (EEG). During the past 2 years (1986-1987), 8 cases of GTS were diagnosed in the pediatric department of National Taiwan University Hospital. Three of them presented epileptiform discharges. Diffuse bilateral parieto-occipital spikes in waking and light sleep periods were noted in case 1, who was a 10-year-old girl. Case 2 was a 9-year-old boy, his EEG showed sporadic spikes over right fronto-central area during light sleep. In case 3, a 6-year-old boy, frequent sharps and spikes appeared in left centro-temporal area in waking and sleep EEG. Case 3 had received antiepileptic therapy. The EEG recovered to normal, the symptoms of the involuntary movement became more prominent. All of the 3 cases improved significantly after haloperidol monotherapy. Based on the clinical observations and literature review, we noted that the incidence of epileptiform discharge in GTS was higher than that in nonepileptic normal population. Although some authors suggested that a seizure state possibly play a subtle role in the genesis of Tourette's symptoms, this inference was not supported by our experience. We observed that haloperidol was effective to this syndrome with or without epileptiform discharge. Therefore, antiepileptic agents, which might alter the metabolism of dopamine, was not recommended for treating GTS patients.

Dopaminergic supersensitivity factors in Tourette's syndrome: a hypothesis

Alterations in striatal dopamine receptor functions are thought to underlie the major symptoms of Tourette's syndrome (TS). In this communication, evidence is presented to suggest that the striatal dopamine receptor supersensitivity in TS may be mediated by alterations in the release and function of dopamine supersensitive factors including prolactin, estrogens, beta-endorphin, melanocyte stimulating hormone (MSH), and adrenal corticotrophic hormone (ACTH). It is suggested that treatment of TS should be directed towards rectifying these endocrine and neuropeptide imbalances.

A case of Tourette's syndrome with midbrain involvement

Several hypotheses have attempted to incriminate a particular anatomical region responsible for the complex symptomatology of Tourette's syndrome (TS). Recently, Devinsky speculated that damage to the peri-aqueductal gray matter (PAG) and midbrain tegmentum may represent the major anatomical site of dysfunction in TS. A patient with TS in whom radiological evidence indicated midbrain involvement may support Devinsky's hypothesis. A 7-year-old boy exhibited motor and vocal tics since the age of four. These were associated with hyperactive behavior, stereotype body movements, abnormal sexual behavior and coprolalia. At the age of five he was placed on methylphenidate for hyperactive behavior which resulted in marked exacerbation of the tics. Family history was unremarkable. Neurological examination was normal with the exception of the tics. Endocrine evaluation, including plasma cortisol, growth hormone, prolactin and TSH were normal with the exception of reduced FSH, LH and testosterone levels. Sexual maturation was normal. MRI head scan was normal with the exception of an asymmetry of the cerebral peduncles with the left larger than the right. CSF examination was normal. While the nature of this patient's radiological abnormalities is not clear, our findings of asymmetric cerebral peduncles associated with TS may support a role for the midbrain in the pathophysiology of TS. The likelihood of the latter assumption seems to be further confirmed by a recent report in which peri-third ventricular and PAG calcifications were detected by CT scan of the head in an adult patient with TS. Further MRI investigations in other cases of TS may clarify the anatomical relationship of the midbrain to the symptomatology of TS.

Auditory event-related potentials in adult patients with Gilles de la Tourette's syndrome in the oddball paradigm

In 20 Tourette patients and 20 control subjects auditory event-related potentials evoked in an oddball paradigm were studied in 2 conditions: a non-motor condition (NMC) in which subjects had to attend tones, and a motor condition (MC) in which they had to press a microswitch to deviant tones. In the NMC patients had a reduced P2 in response to the standards. The deviant-standard subtraction wave forms of the NMC showed a discernible MMN-P165-N2b-P3 complex in the controls, whereas in the patients only the P3 was well developed. In the MC patients had a reduced N1 to the standards. Both groups showed in the deviant-standard subtraction wave forms a clear MMN-P165-N2b-P3 complex, N2b being reduced in the patients. In the patients the P2 amplitude and latency to the standards and in the controls the N2b amplitude in the deviant-standard subtraction wave form were larger in the MC than in the NMC. Both groups also showed a larger P3 and a larger parietal slow positive wave in the MC than in the NMC. The results are discussed in relation to behavioural and neuropsychological disturbances found in Gilles de la Tourette's syndrome.

[Schizophrenic psychosis in a patient with Gilles de la Tourette syndrome]

A 36 year-old female patient with schizophrenia and Tourette syndrome is described. Clinical course, present neurological and psychopathological state, results of psychological testing, computed tomography and MR tomography of the skull, EEG and evoked potentials are reported. Results of neurochemical analysis of CSF and plasma are presented. Possible relationships between Tourette syndrome and schizophrenia are discussed with particular reference to neurochemical findings.

Differential responsiveness to lithium in patients with Tourette disorder

The current status of the use of lithium in the treatment of tic disorders is reviewed. Areas of pathophysiologic overlap between bipolar and tic symptomatology are explored from the standpoint of shared etiology versus co-morbidity. Data from ten cases of children and adolescents with tic disorders treated with lithium are presented. Five exhibited a positive response to tic and associated symptoms, while five did not. Treatment responders versus nonresponders were compared along a number of parameters including co-morbidity with other syndromes, family history, prior medication history, medication used concurrently with lithium, and medication used subsequent to treatment with lithium. Differences between the two groups are explored.

Oculomotor control in Gilles de la Tourette syndrome

Saccadic eye movements, fixation and smooth pursuit were studied in 28 children with Gilles de la Tourette syndrome and found to be normal. A link has been postulated between Gilles de la Tourette syndrome and other movement disorders. The results obtained in the present series do not support this hypothesis.

Tic disorders of childhood

Tic disorders may be classified as simple tics, chronic motor tics or Tourette syndrome, the most severe of the three types. Tourette syndrome is rather uncommon and is often misdiagnosed. Tic disorders of childhood probably have an organic etiology and a genetic component. An increased incidence of obsessive-compulsive behavior, attention deficit disorder and other abnormalities have been reported in Tourette patients. Haloperidol is often useful in controlling severe tic symptoms, while stimulant drugs may worsen the symptoms.

Concordant Gilles de la Tourette's syndrome in monozygotic twins: a clinical, neurophysiological and CT study

A 19-year-old male twin pair were concordant for suffering from Gilles de la Tourette's syndrome in different forms and severity. CT revealed ventricular asymmetries of varying degree within the normal range and there were no neurophysiological abnormalities. The interrelationship of genetic and environmental factors in phenotyping the syndrome is discussed.