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BACKGROUND: Provisional Tic Disorder (PTD) is common in childhood. The received wisdom among clinicians is that PTD is short-lived and mild, with at most a few tics, and rarely includes complex tics, premonitory phenomena or comorbid illnesses. However, such conclusions come from clinical experience, with biased ascertainment and limited follow-up. METHODS: Prospective study of 89 children with tics starting 0-9 months ago (median 4 months), fewer than half from clinical sources. Follow-up at 12 (± 24, 36, 48) months after the first tic. RESULTS: At study entry, many children had ADHD (39), an anxiety disorder (27), OCD (9) or enuresis (17). All had at least two current tics, with a mean total since onset of 6.9 motor and 2.0 phonic tics. Forty-one had experienced a complex tic, and 69 could suppress some tics. Tics were clinically meaningful: 64 had tics severe enough for a clinical trial, and 76 families sought medical attention for the tics. At 12 months, 79 returned, and 78 still had tics. Of these, 29 manifested no tics during history and extended examination, but only via audio-visual monitoring when the child was seated alone. Only 12/70 now had plans to see a doctor for tics. Most who returned at 2-4 years still had tics known to the child and family, but medical impact was low. CONCLUSIONS: Our results do not contradict previous data, but overturn clinical lore. The data strongly argue against the longstanding but arbitrary tradition of separating tic disorders into recent-onset versus chronic.
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Trastornos de Tic , Humanos , Trastornos de Tic/diagnóstico , Trastornos de Tic/psicología , Masculino , Femenino , Niño , Estudios Prospectivos , Preescolar , Trastorno por Déficit de Atención con Hiperactividad/diagnóstico , Trastorno por Déficit de Atención con Hiperactividad/psicología , Comorbilidad , Adolescente , Enuresis/diagnóstico , Enuresis/psicología , Enuresis/epidemiología , Trastornos de Ansiedad/psicología , Trastornos de Ansiedad/diagnóstico , Trastornos de Ansiedad/epidemiología , Trastorno Obsesivo Compulsivo/diagnóstico , Trastorno Obsesivo Compulsivo/psicología , Estudios de SeguimientoRESUMEN
Technologies in the 21st century provide increasingly detailed and accurate maps of brain structure and function. So why don't psychiatrists order brain imaging on all our patients? Here we briefly review major neuroimaging methods and some of their findings in psychiatry. As clinicians and neuroimaging researchers, we are eager to bring brain imaging into daily clinical practice. However, to be clinically useful, any test in medicine must demonstrate adequate test statistics, and show proven benefits that outweigh its risks and costs. In 2024, beyond certain limited circumstances, we have no imaging tests that can meet those standards to provide diagnosis or guide treatment. This cold fact explains why for most psychiatric patients, neuroimaging is not currently recommended by professional organizations or the National Institute of Mental Health.
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Trastornos Mentales , Psiquiatría , Humanos , Trastornos Mentales/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Neuroimagen , Psiquiatría/métodos , PsiquiatrasRESUMEN
BACKGROUND: Many children with tic disorders outgrow their tics, but little is known about the proportion of individuals who will continue to require specialist services in adulthood and which variables are associated with tic persistence. OBJECTIVES: The aims were to estimate the proportion of individuals first diagnosed with tic disorders in childhood who continued to receive tic disorder diagnoses after age 18 years and to identify risk factors for persistence. METHODS: In this Swedish nationwide cohort study including 3761 individuals diagnosed with tic disorders in childhood, we calculated the proportion of individuals whose diagnoses persisted into adulthood. Minimally adjusted logistic regression models examined the associations between sociodemographic, clinical, and family variables and tic disorder persistence. A multivariable model was then fitted, including only variables that were statistically significant in the minimally adjusted models. RESULTS: Seven hundred and fifty-four (20%) children with tic disorders received a diagnosis of a chronic tic disorder in adulthood. Psychiatric comorbidity in childhood (particularly attention-deficit hyperactivity disorder, obsessive-compulsive disorder, pervasive developmental disorders, and anxiety disorders) and psychiatric disorders in first-degree relatives (particularly tic and anxiety disorders) were the strongest risk factors for persistence. We did not observe statistically significant associations with socioeconomic variables, perinatal complications, comorbid autoimmune diseases, or family history of autoimmune diseases. All statistically significant variables combined explained approximately 10% of the variance in tic disorder persistence (P < 0.0001). CONCLUSIONS: Childhood psychiatric comorbidities and family history of psychiatric disorders were the strongest risk factors associated with tic disorder persistence into adulthood. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
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Trastorno por Déficit de Atención con Hiperactividad , Enfermedades Autoinmunes , Trastornos de Tic , Tics , Síndrome de Tourette , Niño , Femenino , Embarazo , Humanos , Adolescente , Tics/complicaciones , Síndrome de Tourette/psicología , Estudios de Cohortes , Trastornos de Tic/complicaciones , Trastorno por Déficit de Atención con Hiperactividad/diagnóstico , Comorbilidad , Factores de Riesgo , Enfermedades Autoinmunes/complicacionesRESUMEN
OBJECTIVE: Recent introduction of a commercial electronic medical record (EMR) system at the authors' institution raised a number of questions about documenting visits for presymptomatic testing for Huntington's disease (HD). Specifically, adoption of the EMR potentially compromised patient confidentiality and the personal delivery of test results, both of which are strongly recommended by professional consensus and lay organizations. METHODS: The authors surveyed peer institutions about their experience with EMR systems in the setting of presymptomatic testing for HD. RESULTS: Answers from 10 well-known HD specialty centers demonstrated a wide variety of approaches to managing these concerns. The responses did not clarify how to resolve the collision between the virtues of a shared medical record and the goal of patient control of sensitive medical information. CONCLUSIONS: These results demonstrate that important issues remain unresolved. The authors propose that medical record systems must adapt to and respect the patient's desires for confidentiality and allow people undergoing presymptomatic testing to restrict access to this sensitive information.
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Confidencialidad/normas , Registros Electrónicos de Salud/normas , Enfermedad de Huntington/genética , Síntomas Prodrómicos , Adulto , Humanos , Enfermedad de Huntington/diagnósticoRESUMEN
OBJECTIVE: Limited evidence is available to guide treatment of depression for persons with epilepsy. We evaluated the comparative effectiveness of sertraline and cognitive behavior therapy (CBT) for depression, quality of life, seizures, and adverse treatment effects. METHODS: We randomly assigned 140 adult outpatients with epilepsy and current major depressive disorder to sertraline or weekly CBT for 16 weeks. The primary outcome was remission from depression based on the Mini International Neuropsychiatric Interview (MINI). Secondary outcomes included the Quality of Life in Epilepsy Inventory-89 (QOLIE-89) seizure rates, the Adverse Events Profile (AEP), the Beck Depression Inventory, and MINI Suicide Risk Module. RESULTS: In the intention-to-treat analysis, 38 (52.8%; 95% confidence interval [CI] = ±12) of the 72 subjects assigned to sertraline and 41 (60.3%; 95% CI = ±11.6) of the 68 subjects in the CBT group achieved remission; the lower bound of efficacy for both groups was greater than our historical placebo control group upper bound of 33.7%. Difference in time to remission between groups was 2.8 days (95% CI = ±0.43; p = 0.79). The percent improvement of mean QOLIE-89 scores was significant for both the CBT (25.7%; p < 0.001) and sertraline (28.3%; p < 0.001) groups. The difference in occurrence of generalized tonic-clonic seizures between groups was 0.3% (95% CI = ±8.6; p = 0.95). Suicide risk at final assessment was associated with persistent depression (p < 0.0001) but not seizures or sertraline. INTERPRETATION: Depression remitted in just over one-half of subjects following sertraline or CBT. Despite the complex psychosocial disability associated with epilepsy, improving depression benefits quality of life. Serotonin reuptake inhibition does not appear to increase seizures or suicidality in persons with epilepsy. ANN NEUROL 2019;86:552-560.
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Terapia Cognitivo-Conductual , Trastorno Depresivo Mayor/tratamiento farmacológico , Trastorno Depresivo Mayor/terapia , Epilepsia/tratamiento farmacológico , Epilepsia/terapia , Sertralina/uso terapéutico , Adulto , Anciano , Trastorno Depresivo Mayor/complicaciones , Epilepsia/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Inhibidores Selectivos de la Recaptación de Serotonina/uso terapéutico , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND: Dopamine D2 receptor antagonists used to treat Tourette syndrome may have inadequate responses or intolerable side effects. We present results of a 4-week randomized, double-blind, placebo-controlled crossover study evaluating the safety, tolerability, and efficacy of the D1 receptor antagonist ecopipam in children and adolescents with Tourette syndrome. METHODS: Forty youth aged 7 to 17 years with Tourette syndrome and a Yale Global Tic Severity Scale - total tic score of ≥20 were enrolled and randomized to either ecopipam (50 mg/day for weight of <34 kg, 100 mg/day for weight of >34 kg) or placebo for 30 days, followed by a 2-week washout and then crossed to the alternative treatment for 30 days. Stimulants and tic-suppressing medications were excluded. The primary outcome measure was the total tic score. Secondary outcomes included obsessive compulsive and attention deficit/hyperactivity disorder scales. RESULTS: Relative to changes in placebo, reduction in total tic score was greater for ecopipam at 16 days (mean difference, -3.7; 95% CI, -6.5 to -0.9; P = 0.011) and 30 days (mean difference, -3.2; 95% CI, -6.1 to -0.3; P = 0.033). There were no weight gain, drug-induced dyskinesias, or changes in laboratory tests, electrocardiograms, vital signs, or comorbid symptoms. Dropout rate was 5% (2 of 40). Adverse events reported for both treatments were rated predominantly mild to moderate, with only 5 rated severe (2 for ecopipam and 3 for placebo). CONCLUSIONS: Ecopipam reduced tics and was well tolerated. This placebo-controlled study of ecopipam supports further clinical trials in children and adolescents with Tourette syndrome. © 2018 International Parkinson and Movement Disorder Society.
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Benzazepinas/uso terapéutico , Antagonistas de Dopamina/uso terapéutico , Síndrome de Tourette/tratamiento farmacológico , Adolescente , Niño , Estudios Cruzados , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Masculino , Evaluación de Resultado en la Atención de Salud , Índice de Severidad de la EnfermedadRESUMEN
Patients with Parkinson's disease psychosis (PDP) are often treated with an atypical antipsychotic, especially quetiapine or clozapine, but side effects, lack of sufficient efficacy, or both may motivate a switch to pimavanserin, the first medication approved for management of PDP. How best to implement a switch to pimavanserin has not been clear, as there are no controlled trials or case series in the literature to provide guidance. An abrupt switch may interrupt partially effective treatment or potentially trigger rebound effects from antipsychotic withdrawal, whereas cross-taper involves potential drug interactions. A panel of experts drew from published data, their experience treating PDP, lessons from switching antipsychotic drugs in other populations, and the pharmacology of the relevant drugs, to establish consensus recommendations. The panel concluded that patients with PDP can be safely and effectively switched from atypical antipsychotics used off label in PDP to the recently approved pimavanserin by considering each agent's pharmacokinetics and pharmacodynamics, receptor interactions, and the clinical reason for switching (efficacy or adverse events). Final recommendations are that such a switch should aim to maintain adequate 5-HT2A antagonism during the switch, thus providing a stable transition so that efficacy is maintained. Specifically, the consensus recommendation is to add pimavanserin at the full recommended daily dose (34 mg) for 2-6 weeks in most patients before beginning to taper and discontinue quetiapine or clozapine over several days to weeks. Further details are provided for this recommendation, as well as for special clinical circumstances where switching may need to proceed more rapidly.
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Antiparkinsonianos/administración & dosificación , Antipsicóticos/administración & dosificación , Sustitución de Medicamentos/métodos , Enfermedad de Parkinson/tratamiento farmacológico , Piperidinas/administración & dosificación , Guías de Práctica Clínica como Asunto , Trastornos Psicóticos/tratamiento farmacológico , Urea/análogos & derivados , Antiparkinsonianos/efectos adversos , Antiparkinsonianos/uso terapéutico , Antipsicóticos/efectos adversos , Antipsicóticos/uso terapéutico , Consenso , Sustitución de Medicamentos/normas , Humanos , Uso Fuera de lo Indicado , Enfermedad de Parkinson/complicaciones , Piperidinas/efectos adversos , Piperidinas/uso terapéutico , Trastornos Psicóticos/etiología , Antagonistas del Receptor de Serotonina 5-HT2/administración & dosificación , Antagonistas del Receptor de Serotonina 5-HT2/efectos adversos , Antagonistas del Receptor de Serotonina 5-HT2/uso terapéutico , Urea/administración & dosificación , Urea/efectos adversos , Urea/uso terapéuticoRESUMEN
Motor and vocal tics are relatively common motor manifestations identified as the core features of Tourette's syndrome (TS). Although traditional descriptions have focused on objective phenomenological observations, such as anatomical location, number and frequency of tics, patients' first-person accounts have consistently reported characteristic subjective correlates. These sensory phenomena are often described as a feeling of mounting inner tension or urge to move ("premonitory urge"), which is transiently relieved by tic expression. This article reviews the existing literature on the clinical and neurobiological aspects of the premonitory urge in patients with TS, with focus on its pathophysiology and possible treatment implications.
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Neurología/métodos , Síndrome de Tourette/fisiopatología , Síndrome de Tourette/terapia , Bases de Datos Bibliográficas/estadística & datos numéricos , Humanos , Trastornos de Tic/fisiopatología , Tics/fisiopatología , Síndrome de Tourette/diagnósticoRESUMEN
In humans, the A1 (T) allele of the dopamine (DA) D2 receptor/ankyrin repeat and kinase domain containing 1 (DRD2/ANKK1) TaqIA (rs1800497) single nucleotide polymorphism has been associated with reduced striatal DA D2/D3 receptor (D2/D3R) availability. However, radioligands used to estimate D2/D3R are displaceable by endogenous DA and are nonselective for D2R, leaving the relationship between TaqIA genotype and D2R specific binding uncertain. Using the positron emission tomography (PET) radioligand, (N-[(11) C]methyl)benperidol ([(11) C]NMB), which is highly selective for D2R over D3R and is not displaceable by endogenous DA, the current study examined whether DRD2/ANKK1 TaqIA genotype predicts D2R specific binding in two independent samples. Sample 1 (n = 39) was composed of obese and nonobese adults; sample 2 (n = 18) was composed of healthy controls, unmedicated individuals with schizophrenia, and siblings of individuals with schizophrenia. Across both samples, A1 allele carriers (A1+) had 5 to 12% less striatal D2R specific binding relative to individuals homozygous for the A2 allele (A1-), regardless of body mass index or diagnostic group. This reduction is comparable to previous PET studies of D2/D3R availability (10-14%). The pooled effect size for the difference in total striatal D2R binding between A1+ and A1- was large (0.84). In summary, in line with studies using displaceable D2/D3R radioligands, our results indicate that DRD2/ANKK1 TaqIA allele status predicts striatal D2R specific binding as measured by D2R-selective [(11) C]NMB. These findings support the hypothesis that DRD2/ANKK1 TaqIA allele status may modify D2R, perhaps conferring risk for certain disease states.
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Repetición de Anquirina/genética , Cuerpo Estriado/metabolismo , Obesidad/genética , Polimorfismo de Nucleótido Simple , Receptores de Dopamina D2/genética , Esquizofrenia/genética , Adolescente , Adulto , Alelos , Benperidol/análogos & derivados , Benperidol/farmacocinética , Estudios de Casos y Controles , Cuerpo Estriado/diagnóstico por imagen , Femenino , Heterocigoto , Humanos , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Unión Proteica , Radiofármacos/farmacocinética , Receptores de Dopamina D2/química , Receptores de Dopamina D2/metabolismoRESUMEN
Tourette syndrome (TS) is a developmental neuropsychiatric disorder characterized by motor and vocal tics. Individuals with TS would benefit greatly from advances in prediction of symptom timecourse and treatment effectiveness. As a first step, we applied a multivariate method - support vector machine (SVM) classification - to test whether patterns in brain network activity, measured with resting state functional connectivity (RSFC) MRI, could predict diagnostic group membership for individuals. RSFC data from 42 children with TS (8-15 yrs) and 42 unaffected controls (age, IQ, in-scanner movement matched) were included. While univariate tests identified no significant group differences, SVM classified group membership with ~70% accuracy (p < .001). We also report a novel adaptation of SVM binary classification that, in addition to an overall accuracy rate for the SVM, provides a confidence measure for the accurate classification of each individual. Our results support the contention that multivariate methods can better capture the complexity of some brain disorders, and hold promise for predicting prognosis and treatment outcome for individuals with TS.
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Imagen por Resonancia Magnética/métodos , Máquina de Vectores de Soporte/normas , Síndrome de Tourette/clasificación , Síndrome de Tourette/diagnóstico por imagen , Adolescente , Estudios de Casos y Controles , Niño , Femenino , Humanos , Masculino , Modelos Neurológicos , Análisis Multivariante , Red Nerviosa , PronósticoRESUMEN
The basal ganglia (BG) comprise a set of subcortical nuclei with sensorimotor, cognitive, and limbic subdivisions, indicative of functional organization. BG dysfunction in several developmental disorders suggests the importance of the healthy maturation of these structures. However, few studies have investigated the development of BG functional organization. Using resting-state functional connectivity MRI (rs-fcMRI), we compared human child and adult functional connectivity of the BG with rs-fcMRI-defined cortical systems. Because children move more than adults, customized preprocessing, including volume censoring, was used to minimize motion-induced rs-fcMRI artifact. Our results demonstrated functional organization in the adult BG consistent with subdivisions previously identified in anatomical tracing studies. Group comparisons revealed a developmental shift in bilateral posterior putamen/pallidum clusters from preferential connectivity with the somatomotor "face" system in childhood to preferential connectivity with control/attention systems (frontoparietal, ventral attention) in adulthood. This shift was due to a decline in the functional connectivity of these clusters with the somatomotor face system over development, and no change with control/attention systems. Applying multivariate pattern analysis, we were able to reliably classify individuals as children or adults based on BG-cortical system functional connectivity. Interrogation of the features driving this classification revealed, in addition to the somatomotor face system, contributions by the orbitofrontal, auditory, and somatomotor hand systems. These results demonstrate that BG-cortical functional connectivity evolves over development, and may lend insight into developmental disorders that involve BG dysfunction, particularly those involving motor systems (e.g., Tourette syndrome).
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Ganglios Basales/fisiología , Corteza Cerebral/fisiología , Red Nerviosa/fisiología , Adulto , Factores de Edad , Ganglios Basales/crecimiento & desarrollo , Mapeo Encefálico , Corteza Cerebral/crecimiento & desarrollo , Niño , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Red Nerviosa/crecimiento & desarrollo , Vías Nerviosas/crecimiento & desarrollo , Vías Nerviosas/fisiologíaRESUMEN
OBJECTIVE: We developed a novel method to map behavioral effects of deep brain stimulation (DBS) across a 3-dimensional brain region and to assign statistical significance after stringent type I error correction. This method was applied to behavioral changes in Parkinson disease (PD) induced by subthalamic nucleus (STN) DBS to determine whether these responses depended on anatomical location of DBS. METHODS: Fifty-one PD participants with STN DBS were evaluated off medication, with DBS off and during unilateral STN DBS with clinically optimized settings. Dependent variables included DBS-induced changes in Unified Parkinson Disease Rating Scale (UPDRS) subscores, kinematic measures of bradykinesia and rigidity, working memory, response inhibition, mood, anxiety, and akathisia. Weighted t tests at each voxel produced p images showing where DBS most significantly affected each dependent variable based on outcomes of participants with nearby DBS. Finally, a permutation test computed the probability that this p image indicated significantly different responses based on stimulation site. RESULTS: Most motor variables improved with DBS anywhere in the STN region, but several motor, cognitive, and affective responses significantly depended on precise location stimulated, with peak p values in superior STN/zona incerta (quantified bradykinesia), dorsal STN (mood, anxiety), and inferior STN/substantia nigra (UPDRS tremor, working memory). INTERPRETATION: Our method identified DBS-induced behavioral changes that depended significantly on DBS site. These results do not support complete functional segregation within STN, because movement improved with DBS throughout, and mood improved with dorsal STN DBS. Rather, findings support functional convergence of motor, cognitive, and limbic information in STN.
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Mapeo Encefálico/métodos , Estimulación Encefálica Profunda/métodos , Enfermedad de Parkinson/terapia , Núcleo Subtalámico/anatomía & histología , Núcleo Subtalámico/fisiología , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/fisiopatología , Resultado del TratamientoRESUMEN
Tourette syndrome (TS) affects about 0.5% of the population worldwide, but only sparse and conflicting data exist on TS prevalence among minority samples. Here we used VISIT-TS (a survey preceded by a short video showing tic phenomenology) and community outreach to provide estimates of tic disorder prevalence in African Americans. Community health workers (CHWs) left flyers at households in a predominantly minority neighborhood and approached people at a community health fair. Of 606 such contacts, 222 individuals agreed to discuss the study. Of these, 70% enrolled, of whom 82% identified as Black and 64% female. The VISIT-TS was well received. Lifetime prevalence of TS or another chronic tic disorder (TS/CTD) was 3.2%, and 31% endorsed any lifetime simple tic. The number of enrolled Black participants is remarkable compared to earlier TS studies, allowing one of the first prevalence estimates in this population (TS 2.3%, TS/CTD 3.9%). Tic disorders were endorsed only by Black respondents, though the small White sample precluded statistical comparison. Women had higher rates than men of TS (M:F = 0:1) and of any lifetime simple tic (M:F = 0.85), differing significantly from the expected 4:1 ratio (p = .009 and p < .001, respectively). For TS/CTD the ratio was 1.2:1 (p > .15). We conclude that VISIT-TS is a feasible tic screening tool in a minority population, that CHW community outreach increases enrollment of Black participants, that TS/CTD is no less common in this population, and that tics were as common in female as in male respondents.
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In this, the tenth annual update for the F1000Research Tics collection, we summarize research reports from 2023 on Gilles de la Tourette syndrome and other tic disorders. The authors welcome article suggestions and thoughtful feedback from readers.
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Síndrome de Tourette , Síndrome de Tourette/terapia , Humanos , Investigación Biomédica/tendenciasRESUMEN
Transcranial magnetic stimulation (TMS) and deep brain stimulation (DBS) can treat some neuropsychiatric disorders, but there is no consensus approach for identifying new targets. We localized causal circuit-based targets for anxiety that converged across multiple natural experiments. Lesions (n=451) and TMS sites (n=111) that modify anxiety mapped to a common normative brain circuit (r=0.68, p=0.01). In an independent dataset (n=300), individualized TMS site connectivity to this circuit predicted anxiety change (p=0.02). Subthalamic DBS sites overlapping the circuit caused more anxiety (n=74, p=0.006), thus demonstrating a network-level effect, as the circuit was derived without any subthalamic sites. The circuit was specific to trait versus state anxiety in datasets that measured both (p=0.003). Broadly, this illustrates a pathway for discovering novel circuit-based targets across neuropsychiatric disorders.
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Previous PET imaging studies have demonstrated mixed findings regarding dopamine D2/D3 receptor availability in obese relative to nonobese humans. Nonspecific D2/D3 radioligands do not allow for separate estimation of D2 receptor (D2R) and D3 receptor (D3R) subtypes of the D2 receptor family, which may play different roles in behavior and are distributed differently throughout the brain. These radioligands are also displaceable by endogenous dopamine, confounding interpretation of differences in receptor availability with differing levels of dopamine release. The present study used PET imaging with the D2R-selective radioligand (N-[(11)C] methyl)benperidol ([(11)C]NMB), which is nondisplaceable by endogenous dopamine, to estimate D2R specific binding (BPND) and its relationship to body mass index (BMI) and age in 15 normal-weight (mean BMI = 22.6 kg/m(2)) and 15 obese (mean BMI = 40.3 kg/m(2)) men and women. Subjects with illnesses or taking medications that interfere with dopamine signaling were excluded. Striatal D2R BPND was calculated using the Logan graphical method with cerebellum as a reference region. D2R BPND estimates were higher in putamen and caudate relative to nucleus accumbens, but did not differ between normal-weight and obese groups. BMI values did not correlate with D2R BPND . Age was negatively correlated with putamen D2R BPND in both groups. These results suggest that altered D2R specific binding is not involved in the pathogenesis of obesity per se and underscore the need for additional studies evaluating the relationship between D3R, dopamine reuptake, or endogenous dopamine release and human obesity.
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Obesidad/metabolismo , Receptores de Dopamina D2/metabolismo , Adulto , Factores de Edad , Benperidol/administración & dosificación , Benperidol/análogos & derivados , Índice de Masa Corporal , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Obesidad/diagnóstico por imagen , Obesidad/etiología , Especificidad de Órganos , Tomografía de Emisión de PositronesRESUMEN
Median nerve stimulation (MNS) at 10-12 Hz was recently proposed as a treatment for Tourette syndrome and other chronic tic disorders (TS/CTD). We report on 31 participants ages 15-64 with TS/CTD in an open-label, comparative (within-group, several time points) study of MNS (ClinicalTrials.gov registration number NCT05016765). Participants were recruited from completers of a randomized controlled trial (RCT) of MNS and were given a transcutaneous electrical nerve stimulation (TENS) unit to use as desired for 12 Hz MNS for 4 weeks. Participants were instructed to complete surveys regarding tic symptoms and stimulation discomfort before and after stimulation, as well as twice daily when randomly prompted by text message. Participants also completed an extensive final survey. Twenty-seven participants completed the study. Median device use was 1.5 days per week and 50 min per day used. Tic frequency improved during MNS (mean improvement: 1.0 on a 0-5 scale, p < 0.001), as did tic intensity (mean improvement: 0.9, p < 0.001). Mean discomfort was mild (1.2 on a 3-point scale). In total, 21 participants (78%) planned to continue using the device. Participants' results in this study did not correlate significantly with their results in the blinded RCT. We found MNS to improve tic frequency and intensity with minimal side effects.
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A prior study showed that rhythmic, but not arrhythmic, 12 Hz stimulation of the median nerve (MNS) entrained sensorimotor cortex EEG signal, and found that 10 Hz MNS improved tics in Tourette syndrome (TS). However, no control condition was tested and stimulation blocks lasted only 1 minute. We set out to replicate the TS results and to test whether tic improvement occurs by the proposed cortical entrainment mechanism. Thirty-two people with TS, age 15-64, completed two study visits with repeated MNS on and off blocks in random order, one visit for rhythmic and one for arrhythmic MNS. Subjects and staff were blind to order; a video rater was additionally blind to stimulation and to order of visits and blocks. Rhythmic MNS at 10 Hz improved tics. Both rhythmic and arrhythmic 12 Hz MNS improved tic frequency, intensity and urges without significant difference. Participant masking was effective and there was no carryover effect. Several participants described dramatic benefit. Discomfort was minimal. MNS benefit did not persist after the end of stimulation. These results replicate the tic benefit from MNS, but show that the EEG entrainment hypothesis cannot explain that benefit. Another electrophysiological mechanism may explain benefit; alternatively, these data do not exclude a placebo effect. Registration: ClinicalTrials.gov , NCT04731714 .