Co-morbid tics and stereotypies: a systematic literature review.

BACKGROUND: Tics and stereotypies are childhood-onset repetitive behaviours that can pose significant diagnostic challenges in clinical practice. Both tics and stereotypies are characterised by a complex co-morbidity profile, however little is known about the co-occurrence of these hyperkinetic disorders in the same patient population. OBJECTIVE: This review aimed to assess the relationship between tics and stereotypies when these conditions present in co-morbidity. METHODS: We conducted a systematic literature review of original studies on co-morbid tics and stereotypies, according to the standards outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. RESULTS: Our literature search identified six studies of suitable sample size (n ≥ 40) presenting data on the association between tics and stereotypies in otherwise typically developing patients. A considerable proportion (23%) of patients diagnosed with stereotypic movement disorder present with co-morbid tics (range 18-43%). Likewise, the prevalence of primary stereotypies is increased in patients with tic disorders such as Tourette syndrome (8%, range 6-12%). DISCUSSION: Tics and stereotypies can often develop in co-morbidity. The association of tics and stereotypies in the same patient has practical implications, in consideration of the different treatment approaches. Future research should focus on the assessment and management of both conditions, particularly in special populations (e.g. patients with pervasive developmental disorders).

Gilles de la Tourette syndrome as a rare co-morbidity of Klinefelter syndrome.

BACKGROUND: Klinefelter syndrome (47, XXY) is the most common sex chromosome aneuploidy. In addition to male hypergonadotropic hypogonadism, a wide range of neurodevelopmental disorders, anxiety and affective symptoms have been reported in a substantial proportion of cases. CASE DESCRIPTION: We document the rare case of a 43-year-old man diagnosed with Klinefelter syndrome and co-morbid Gilles de la Tourette syndrome. He presented with multiple motor and vocal tics since adolescence, as well as anxiety and affective symptoms as his main tic-exacerbating factors. Tic severity was rated as marked (Yale Global Tic Severity Scale score of 78/100), and recommendations for the treatment of both tics and psychiatric co-morbidities were formulated. DISCUSSION: Neurodevelopmental tics in the context of Klinefelter syndrome have been previously documented in three cases only. Gilles de la Tourette syndrome is 3-4 times more common in males than females and its etiological factors include multiple genetic components (genetic heterogeneity). Our case report widens the spectrum of neurodevelopmental disorders observed in the context of Klinefelter syndrome and contributes to genetic research on the role of the X chromosome in the pathophysiology of tic disorders.

Distinguishing functional from primary tics: a study of expert video assessments.

BACKGROUND: Reliably applied criteria to differentiate functional from primary tics are lacking. In the absence of biological markers, the development of new diagnostic criteria to assist clinicians is predicated on expert judgement and consensus. This study examines the level of diagnostic agreement of experts in tic disorders using video footage and clinical descriptions. METHODS: Using a two-part survey, eight experts in the diagnosis and management of tics were first asked to study 24 case videos of adults with primary tics, functional tics or both and to select a corresponding diagnosis. In the second part of the survey, additional clinical information was provided, and the diagnosis was then reconsidered. Inter-rater agreement was measured using Fleiss' kappa. In both study parts, the factors which influenced diagnostic decision-making and overall diagnostic confidence were reviewed. RESULTS: Based on phenomenology alone, the diagnostic agreement among the expert raters was only fair for the pooled diagnoses (κ=0.21) as well as specifically for functional (κ=0.26) and primary tics (κ=0.24). Additional clinical information increased overall diagnostic agreement to moderate (κ=0.51) for both functional (κ=0.6) and primary tics (κ=0.57). The main factors informing diagnosis were tic semiology, age at tic onset, presence of premonitory urges, tic suppressibility, the temporal latency between tic onset and peak severity, precipitants and tic triggers and changes in the overall phenotypic presentation. CONCLUSIONS: This study confirmed that in the absence of clinical information, the diagnostic distinction between primary and functional tics is often difficult, even for expert clinicians.

Functional tics: Expanding the phenotypes of functional movement disorders?

BACKGROUND AND PURPOSE: Until the outbreak reported during the COVID-19 pandemic, functional tics were considered to be a relatively rare clinical phenotype, as opposed to other functional movement disorders such as functional tremor and dystonia. To better characterize this phenotype, we compared the demographic and clinical characteristics of patients who developed functional tics during the pandemic and those of patients with other functional movement disorders. METHODS: Data from 110 patients were collected at the same neuropsychiatry centre: 66 consecutive patients who developed functional tics without other functional motor symptoms or neurodevelopmental tics and 44 patients with a mix of functional dystonia, tremor, gait, and myoclonus. RESULTS: Both groups were characterized by female sex preponderance (70%-80%) and (sub)acute onset of functional symptoms (~80%). However, patients with functional tics had a significantly earlier age at onset of functional symptoms (21 vs. 39 years). Exposure to relevant social media content was reported by almost half of the patients with functional tics, but by none of the patients with other functional movement disorders. Comorbidity profiles were similar, with relatively high rates of anxiety/affective symptoms and other functional neurological symptoms (nonepileptic attacks). CONCLUSIONS: Patients who developed functional tics during the pandemic represent a phenotypic variant of the wider group of patients with functional movement disorders, associated with younger age at onset and influenced by pandemic-related factors, including increased exposure to specific social media content. Diagnostic protocols and treatment interventions should be tailored to address the specific features of this newly defined phenotype.

European Society for the Study of Tourette Syndrome 2022 criteria for clinical diagnosis of functional tic-like behaviours: International consensus from experts in tic disorders.

BACKGROUND AND PURPOSE: In 2020, health professionals witnessed a dramatic increase in referrals of young people with rapid onset of severe tic-like behaviours. We assembled a working group to develop criteria for the clinical diagnosis of functional tic-like behaviours (FTLBs) to help neurologists, pediatricians, psychiatrists, and psychologists recognize and diagnose this condition. METHODS: We used a formal consensus development process, using a multiround, web-based Delphi survey. The survey was based on an in-person discussion at the European Society for the Study of Tourette Syndrome (ESSTS) meeting in Lausanne in June 2022. Members of an invited group with extensive clinical experience working with patients with Tourette syndrome and FTLBs discussed potential clinical criteria for diagnosis of FTLBs. An initial set of criteria were developed based on common clinical experiences and review of the literature on FTLBs and revised through iterative discussions, resulting in the survey items for voting. RESULTS: In total, 24 members of the working group were invited to participate in the Delphi process. We propose that there are three major criteria and two minor criteria to support the clinical diagnosis of FTLBs. A clinically definite diagnosis of FTLBs can be confirmed by the presence of all three major criteria. A clinically probable diagnosis of FTLBs can be confirmed by the presence of two major criteria and one minor criterion. CONCLUSIONS: Distinguishing FTLBs from primary tics is important due to the distinct treatment paths required for these two conditions. A limitation of the ESSTS 2022 criteria is that they lack prospective testing of their sensitivity and specificity.

The Western origins of mindfulness therapy in ancient Rome.

Stoic philosophy has multiple parallels with cognitive behavioural therapy interventions. In their ancient texts, the Roman Stoics present a set of theoretical principles and behavioural strategies that are directly relevant to the clinical care of patients with a wide range of neuropsychiatric conditions. Mindfulness is a key component of the 'third wave' of modern psychotherapy that closely resembles the ancient Stoic practice of attention or 'concentration on the present moment'. Stoic mindfulness draws attention to one of the main principles driving both Stoicism and modern psychotherapy: the assumption that cognitive activity (reasoning) mediates emotions and behaviours. This principle can be traced back to Epictetus' Enchiridion, where he recognises that 'men are disturbed not by things, but by the views which they take of things'. It has been shown that cognitive behavioural therapies and mindfulness-based interventions directed at patients with neuropsychiatric disorders were originally developed as Stoic-inspired treatment interventions. Both Albert Ellis and Aaron Beck (the founders of rational emotive behaviour therapy and cognitive behavioural therapy, respectively) explicitly acknowledged the role of Stoicism as the philosophical precursor of their treatment approaches. The effective implementation of evidence-based guidelines would benefit from an increased awareness of the influence of the Stoic tradition of philosophical therapy on the treatment approaches currently in use in neuropsychiatry.

Can Stoicism inspire stuttering intervention? The clinical usefulness of an ancient philosophy.

BACKGROUND: A range of psychotherapies are effective in managing an individual's personal reactions to stuttering and reducing the impact stuttering has on their lives. Many of these therapies, such as cognitive behavioural therapy, have their origins in Stoicism, an ancient Greek philosophy founded in 301 bce. Stoicism remains a relatively unexplored topic in the psychotherapy and speech and language therapy literatures. AIMS: This paper aims to highlight the potential benefits of integrating Stoic principles and techniques into stuttering intervention. METHODS: This aim is achieved through a discussion on Stoic philosophy and the range of techniques that have informed modern evidence-based psychotherapies that are effective with the stuttering population. MAIN CONTRIBUTION: This paper initiates an important conversation on the usefulness of Stoicism to the field of stuttering. Key recommendations are provided for the integration of Stoic philosophy into future clinical and research practice related to stuttering. CONCLUSIONS: Stoicism offers philosophical guidance for the art of living, but also provides a range of strategies and practical techniques that have potential to expand the clinical toolkit of modern psychotherapy and speech and language therapy. Scientific validation of the clinical application of Stoicism is recommended to exploit its effectiveness with the stuttering population. WHAT THIS PAPER ADDS: What is already known on the subject Stoicism is an ancient philosophy that has informed modern-day psychotherapies including cognitive behavioural therapy (CBT) and acceptance and commitment therapy (ACT). Such therapies are recommended for use with individuals who stutter to target their personal reactions to stuttering and reduce any adverse impacts on their lives. What this paper adds to existing knowledge This paper discusses the principles and techniques of Stoicism with reference to how they align with modern psychotherapeutic approaches and speech and language therapy interventions used with individuals who stutter. Clinical implications and directions for future research are also presented. What are the potential or actual clinical implications of this work? Speech and language therapists (SLTs) are recommended to continue their use of psychotherapies such as CBT and ACT with individuals who stutter. In addition, SLTs are advised to explore Stoicism and its range of techniques to better understand the philosophical underpinnings of evidence-based psychotherapies and to expand their clinical toolkit.

European clinical guidelines for Tourette syndrome and other tic disorders-version 2.0. Part IV: deep brain stimulation.

In 2011 the European Society for the Study of Tourette Syndrome (ESSTS) published its first European clinical guidelines for the treatment of Tourette Syndrome (TS) with part IV on deep brain stimulation (DBS). Here, we present a revised version of these guidelines with updated recommendations based on the current literature covering the last decade as well as a survey among ESSTS experts. Currently, data from the International Tourette DBS Registry and Database, two meta-analyses, and eight randomized controlled trials (RCTs) are available. Interpretation of outcomes is limited by small sample sizes and short follow-up periods. Compared to open uncontrolled case studies, RCTs report less favorable outcomes with conflicting results. This could be related to several different aspects including methodological issues, but also substantial placebo effects. These guidelines, therefore, not only present currently available data from open and controlled studies, but also include expert knowledge. Although the overall database has increased in size since 2011, definite conclusions regarding the efficacy and tolerability of DBS in TS are still open to debate. Therefore, we continue to consider DBS for TS as an experimental treatment that should be used only in carefully selected, severely affected and otherwise treatment-resistant patients.

European clinical guidelines for Tourette syndrome and other tic disorders-version 2.0. Part III: pharmacological treatment.

In 2011, the European Society for the Study of Tourette Syndrome (ESSTS) published the first European guidelines for Tourette Syndrome (TS). We now present an update of the part on pharmacological treatment, based on a review of new literature with special attention to other evidence-based guidelines, meta-analyses, and randomized double-blinded studies. Moreover, our revision took into consideration results of a recent survey on treatment preferences conducted among ESSTS experts. The first preference should be given to psychoeducation and to behavioral approaches, as it strengthens the patients' self-regulatory control and thus his/her autonomy. Because behavioral approaches are not effective, available, or feasible in all patients, in a substantial number of patients pharmacological treatment is indicated, alone or in combination with behavioral therapy. The largest amount of evidence supports the use of dopamine blocking agents, preferably aripiprazole because of a more favorable profile of adverse events than first- and second-generation antipsychotics. Other agents that can be considered include tiapride, risperidone, and especially in case of co-existing attention deficit hyperactivity disorder (ADHD), clonidine and guanfacine. This view is supported by the results of our survey on medication preference among members of ESSTS, in which aripiprazole was indicated as the drug of first choice both in children and adults. In treatment resistant cases, treatment with agents with either a limited evidence base or risk of extrapyramidal adverse effects might be considered, including pimozide, haloperidol, topiramate, cannabis-based agents, and botulinum toxin injections. Overall, treatment of TS should be individualized, and decisions based on the patient's needs and preferences, presence of co-existing conditions, latest scientific findings as well as on the physician's preferences, experience, and local regulatory requirements.

Possible tics diagnosed as stereotypies in patients with severe autism spectrum disorder: a video-based evaluation.

BACKGROUND: The association of stereotypies and tics is not rare in children with severe autism spectrum disorder (ASD). The differential diagnosis between stereotypies and tics in this patient population can be difficult; however, it could be clinically relevant because of treatment implications. METHODS: A total of 108 video recordings of repetitive behaviors in young patients with stereotypies in the context of ASD were reviewed by a movement disorders expert and a trainee, in order to assess the prevalence of possible co-morbid tics. The Modified Rush Videotape Rating Scale (MRVS) was used to rate tic frequency and severity. RESULTS: Out of 27 patients with stereotypies (24 males; mean age 14 years), 18 (67%) reported possible tics. The most frequently observed tics were eye blinking, shoulder shrugging, neck bending, staring, and throat clearing. The mean MRVS score was 5, indicating mild tic severity. The only significant difference between patients with tics and patients without tics was the total number of stereotypies, which was higher in the subgroup of patients without tics (p = 0.01). CONCLUSIONS: Expert review of video-recordings of repetitive behaviors in young patients with ASD and stereotypies suggests the possibility of a relatively high rate of co-morbid tics. These findings need to be integrated with a comprehensive clinical assessment focusing on the diagnostic re-evaluation of heterogeneous motor manifestations.

Tics in patients with encephalitis.

BACKGROUND: Movement disorders have been described in the context of different types of encephalitis. Among hyperkinetic manifestations, tics have sporadically been reported in cases of encephalitis resulting from a range of aetiologies. OBJECTIVE: This review aimed to assess the prevalence and characteristics of tics in patients with encephalitis. METHODS: We conducted a systematic literature review of original studies on the major scientific databases, according to the standards outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. RESULTS: In addition to the established association between tics and encephalitis lethargica, our literature search identified reports of tics in patients with immune-mediated pathologies (including autoimmune encephalitides affecting the N-methyl-D-aspartate receptor, voltage-gated potassium channels, and glycine receptors) and infective processes (ranging from relatively common viral pathogens, such as herpes simplex, to prions, as in Creutzfeldt-Jakob disease). Tics were most commonly reported in the post-encephalitic period and involvement of the basal ganglia was frequently observed. DISCUSSION: The association of new-onset tics and encephalitis, in the background of other neuropsychiatric abnormalities, has practical implications, potentially improving the detection of encephalitis based on clinical features. Future research should focus on the categorisation and treatment of hyperkinetic movement disorders associated with encephalitis.

Levels of diagnostic certainty for nonepileptic attack disorder in the neuropsychiatry setting.

Nonepileptic attack disorder (NEAD) is a medical condition commonly seen in neuropsychiatry services, often as a differential diagnosis of other neuropsychiatric conditions. Recommendations by the International League Against Epilepsy (ILAE) Nonepileptic Seizures Task Force propose a four-level hierarchical approach to the diagnosis of NEAD, based on history, witnessed event, and electroencephalographic (EEG) investigation. We set out to provide the first description of the diagnostic levels of patients with NEAD at a specialist neuropsychiatry clinic. Comprehensive clinical data from 148 consecutive patients with NEAD attending the specialist Neuropsychiatry Clinic run by a single Consultant in Behavioral Neurology were retrospectively reviewed. Patients with NEAD were primarily referred to neuropsychiatry by Consultant Neurologists (n = 94; 63.5%). The majority of patients were female (n = 108; 73.0%), with a disease duration of 7.9 years (standard deviation: 10.4). Anxiety was the most common comorbidity (n = 43; 26.7%). Categorization of patients according to the ILAE Nonepileptic Seizures Task Force criteria was mainly based on clinical features and EEG findings, as only 7 (4.7%) patients had attacks witnessed by a specialist. The largest diagnostic categories were 'possible' (n = 54; 36.5%) and 'clinically established' (n = 40; 27.0%), followed by 'documented' (n = 12; 8.1%) and 'probable' (n = 5; 3.4%). In 125 patients (84.4%), EEGs were performed. Selective serotonin reuptake inhibitors were the most frequently prescribed psychotropic medications (n = 48; 32.4%); 89 patients (60.1%) received behavioral therapy. There were no differences in pharmacological or behavioral management strategies across the patients categorized under different diagnostic levels. Patients with NEAD seen within neuropsychiatry settings are mainly assigned 'possible' and 'clinically established' levels of diagnostic certainty. Difficulty in capturing typical clinical events witnessed by an experienced clinician while on video-EEG can limit the clinical application of the 'documented' diagnostic level. If appropriate, active interventions can be implemented irrespective of diagnostic levels to minimize delays in the neuropsychiatric care pathways.

Nonepileptic attack disorder and functional movement disorder: A clinical continuum?

Nonepileptic attack disorder (NEAD) and functional movement disorder (FMD) are functional neurological disorders commonly seen in neuropsychiatry services. Although their initial referral pathways involve epileptologists (NEAD) and specialists in movement disorders (FMD), these conditions are currently classified as two possible manifestations of a single underlying conversion disorder. We set out to compare the characteristics of patients with NEAD and patients with FMD in order to quantify the degree of overlap between these patient groups. We retrospectively reviewed comprehensive clinical data from 146 consecutive patients with functional neurological disorders (NEAD: n = 117; FMD: n = 29) attending a specialist Neuropsychiatry Clinic run by a single Consultant in Behavioral Neurology. The two clinical groups were directly compared with regard to demographic and clinical characteristics, as well as somatic and psychiatric presentations. The results showed that in most features, there were no significant differences between patients with NEAD and patients with FMD. However, patients with NEAD reported an earlier age at onset (p = 0.033) and a higher proportion of acute onset (p = 0.037), alterations of consciousness (p = 0.001), and headache (p = 0.042), whereas patients with FMD reported a higher prevalence of childhood abuse (p = 0.008), as well as mobility problems (p = 0.007) and comorbid functional symptoms (dysarthria, p = 0.004; dizziness, p = 0.035; weakness, p = 0.049). Despite different phenotypic presentations, NEAD and FMD might represent a clinical continuum, with relevant implications in terms of both diagnostic strategies and treatment approaches.

Relaxation therapy as a treatment for tics in patients with Tourette syndrome: a systematic literature review.

BACKGROUND: Tourette syndrome (TS) is a neurodevelopmental condition characterized by the presence of multiple motor and phonic tics, often associated with co-morbid behavioural problems. Tics can be modulated by environmental factors and are characteristically exacerbated by psychological stress, among other factors. This observation has led to the development of specific behavioural treatment strategies, including relaxation therapy. OBJECTIVE: This review aimed to assess the efficacy of relaxation therapy to control or reduce tic symptoms in patients with TS. METHODS: We conducted a systematic literature review of original studies on the major scientific databases, including Medline, EMBASE, and PsycInfo, according to the standards outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Outcomes measures included both tic severity and tic frequency. RESULTS: Our literature search identified three controlled trials, with a total number of 40 participants (range: 6-18 participants). In all three studies, relaxation therapy decreased the severity and/or the frequency of tic symptoms. However, the only trial comparing relaxation therapy to two other behavioural techniques found relaxation therapy to be the least effective intervention, as it reduced the number of tics by 32% compared to 44% with self-monitoring and 55% with habit reversal. DISCUSSION: The results of this systematic literature review provide initial evidence for the use of relaxation therapy as a behavioural treatment intervention for tics in patients with TS. Caution is needed in the interpretation of these findings, because the reviewed trials had small sample sizes and there was high heterogeneity across the study protocols.

Pharmacotherapy for tics in adult patients with Tourette syndrome and other tic disorders.

BACKGROUND: Tourette syndrome (TS) and persistent motor/vocal tic disorders are neurodevelopmental conditions characterised by the chronic presence of motor and/or vocal tics. Patients with TS often present with co-morbid disorders, especially attention-deficit and hyperactivity disorder (which tends to improve after childhood), and obsessive-compulsive disorder (which can persist in adulthood). We set out to explore pharmacotherapy for tics in adult patients with TS and persistent motor/vocal tic disorders, as well as its relationship with the presence of co-morbid conditions. METHODS: We retrospectively reviewed the clinical characteristics and pharmacotherapy of 192 adult patients with TS (n = 187), persistent motor tic disorder (n = 3) and persistent vocal tic disorder (n = 2) attending a specialist clinic in the UK. RESULTS: Anti-dopaminergic medications (n = 65) and alpha-2-agonists (n = 50) were the most commonly prescribed pharmacotherapy for tic management. A sub-group analysis revealed that co-morbid obsessive-compulsive disorder and sub-threshold obsessive-compulsive behaviours were significantly more common in patients treated with anti-dopaminergic medications than patients taking alpha-2-agonists (p = 0.013 and p = 0.047, respectively). CONCLUSIONS: The use of pharmacotherapy options for tic management observed at a specialist clinic for adults with TS reflects guideline recommendations. We found that the presence of co-morbid obsessive-compulsive disorder/behaviours correlates with the choice of anti-dopaminergic medications over alpha-2-agonists, in line with available evidence on the efficacy of anti-dopaminergic medications for the treatment of specific tic-related behavioural symptoms.

The cognitive neuropsychiatry of Tourette syndrome.

Introduction: Converging evidence from both clinical and experimental studies has shown that Tourette syndrome (TS) is not a unitary condition, but a cluster of multiple phenotypes, which encompass both tics and specific behavioural and cognitive symptoms (mainly attention-deficit and hyperactivity disorder and obsessive-compulsive disorder). Methods: We conducted a narrative review of the recent literature on the cognitive neuropsychiatry of TS. Results: Although clinical research has shown that TS is not associated with cognitive deficits per se, the findings of recent studies have suggested the presence of subtle alterations in specific cognitive functions. A promising line of research on imitative behaviour could provide a common background for the alterations in executive control and social cognition observed in TS. Two different (but not mutually exclusive) neurocognitive theories have recently suggested that TS could originate from altered perception-action binding and social decision-making dysfunction, respectively. Conclusions: Since the presence of behavioural comorbidities influences individualised treatment approaches, it is likely that a more precise characterisation of TS phenotypes, including cognitive aspects, will result in improved levels of care for patients with tic disorders.

Gilles de la Tourette syndrome as a paradigmatic neuropsychiatric disorder.

Gilles de la Tourette syndrome is a chronic and complex tic disorder accompanied by specific behavioral problems in the majority of patients. With its multifaceted interplay between motion and emotion, this condition is a paradigmatic example of the science and art of clinical neuropsychiatry. This review article encompasses the clinical phenomenology of motor and vocal tics and associated sensory experiences (premonitory urges), as well as the behavioral spectrum of the most common comorbidities, including obsessive-compulsive disorder, attention-deficit and hyperactivity disorder, affective symptoms, and impulsivity. Knowledge of the contributions of both tics and behavioral problems to patients' health-related quality of life across the lifespan should assist treating clinicians in formulating a targeted management plan. Although the exact pathophysiology of Gilles de la Tourette syndrome remains elusive, research into therapeutic interventions has expanded the range of available interventions across multiple domains. A thorough understanding of the neurology and psychiatry of this condition is of key importance to meet the needs of this patient population, from the formulation of an accurate diagnosis to the implementation of effective treatment strategies.

Insights from the third international conference on hyperacusis: causes, evaluation, diagnosis, and treatment.

BACKGROUND: Hyperacusis is intolerance of certain everyday sounds that causes significant distress and impairment in social, occupational, recreational, and other day-to-day activities. OBJECTIVE: The aim of this report is to summarize the key findings and conclusions from the Third International Conference on Hyperacusis. TOPICS COVERED: The main topics discussed comprise (1) diagnosis of hyperacusis and audiological evaluations, (2) neurobiological aspect of hyperacusis, (3) misophonia, (4) hyperacusis in autism spectrum disorder, (5) noise sensitivity, (6) hyperacusis-related distress and comorbid psychiatric illness, and (7) audiologist-delivered cognitive behavioral therapy for hyperacusis. CONCLUSIONS: Implications for research and clinical practice are summarised.

Are psychogenic non-epileptic seizures just another symptom of conversion disorder?

BACKGROUND: Psychogenic non-epileptic seizures (PNES) are classified with other functional neurological symptoms as 'Conversion Disorder', but there are reasons to wonder whether this symptomatology constitutes a distinct entity. METHODS: We reviewed the literature comparing PNES with other functional neurological symptoms. RESULTS: We find eight studies that directly examined this question. Though all but one found significant differences-notably in presenting age, trauma history, and dissociation-they were divided on whether these differences represented an important distinction. CONCLUSION: We argue that the aetiological and mechanistic distinctions they support, particularly when bolstered by additional data, give reason to sustain a separation between these conditions.

Systematic review of severity scales and screening instruments for tics: Critique and recommendations.

BACKGROUND: Several clinician, informant, and self-report instruments for tics and associated phenomena have been developed that differ in construct, comprehensiveness, and ease of administration. OBJECTIVE: A Movement Disorders Society subcommittee aimed to rate psychometric quality of severity and screening instruments for tics and related sensory phenomena. METHODS: Following the methodology adopted by previous Movement Disorders Society subcommittee papers, a review of severity and screening instruments for tics was completed, applying a classification as "recommended," "suggested," or "listed" to each instrument. RESULTS: A total of 5 severity scales (Yale Global Tic Severity Scale, Tourette Syndrome Clinical Global Impression, Tourette's Disorder Scale, Shapiro Tourette syndrome Severity Scale, Premonitory Urges for Tics Scale) were "recommended," and 6 (Rush Video-Based Tic Rating Scale, Motor tic, Obsessions and compulsions, Vocal tic Evaluation Survey, Tourette Syndrome Global Scale, Global Tic Rating Scale, Parent Tic Questionnaire, Tourette Syndrome Symptom List) were "suggested." A total of 2 screening instruments (Motor tic, Obsession and compulsions, Vocal tic Evaluation Survey and Autism-Tics, Attention Deficit/Hyperactivity Disorder and Other Comorbidities Inventory) were "recommended," whereas 2 others (Apter 4-questions screening and Proxy Report Questionnaire for Parents and Teachers) were "suggested." CONCLUSIONS: Our review does not support the need for developing new tic severity or screening instruments. Potential objectives of future research include developing a rating instrument targeting the full spectrum of tic-related abnormal behaviors, assessing/screening malignant forms of tic disorders, and developing patient-reported outcome measures. © 2017 International Parkinson and Movement Disorder Society.