Late-onset startle syndrome and obsessive compulsive disorder

A case of late onset sporadic startle syndrome in a patient with a right posterior fossa brain tumour is reported. The exaggerated startle response did not respond to treatment with clonazepam. In addition to anxiety and depression, the patient developed obsessive- compulsive symptoms which responded to behavioural therapy. The possible mechanisms for this unique pattern of symptoms are discussed.     

The semantic Simon effect in Tourette's syndrome and obsessive-compulsive disorder

Core symptoms of Tourette's syndrome (TS) and obsessive-compulsive disorder (OCD) may be attributed to an impairment in inhibitory control. Neuropsychological studies have addressed inhibition in both disorders, but findings have been inconsistent. The aim of this study was to examine cognitive inhibition, using a semantic Simon effect paradigm, in patients with TS and OCD. Furthermore, to address comorbidity a group of TS+OCD patients was also examined. Results indicated that patients with TS and OCD were affected by the inhibitory components of the task. TS groups performed similarly to controls on simple and choice RT tasks, but were particularly compromised as increasingly complex inhibitory demands were imposed. OCD patients were slower and committed more errors than controls, especially in the more cognitively demanding conditions, and were particularly disadvantaged by incongruent stimulus-response compatibilities. Findings implicate possible fronto-striatal dysfunction, are consistent with previously reported inhibitory deficits in TS and OCD, and support the theory that comorbid TS+OCD is more closely linked to pure TS than OCD.     

Inhibition of return in children with Tourette's syndrome and comorbid forms: a preliminary study.

BACKGROUND: This study investigated the nature and functioning of the visual-spatial inhibition of return (IOR) phenomenon in children with "pure" Tourette's syndrome (TS), and those with comorbid forms of TS. METHOD: Children with TS-only and "TS + comorbid" (TS + ADHD +/- OCD) and matched controls performed the inhibition of return (IOR) task, which involved responding to left and right visual targets appearing on a computer screen that were preceded by congruent or incongruent exogenous visual cues. RESULTS: The TS-only group performed similarly on the IOR task to the controls. When the TS-only group was subdivided into children with mild and severe TS symptoms, a post hoc comparison between the controls and severe TS symptom children revealed that these TS children had a reduced magnitude of IOR for targets appearing in the right visual field. The comparison between the TS + comorbid and controls revealed an atypical IOR pattern for the TS + comorbid group. They displayed a loss of normal facilitatory and inhibitory effects for right visual field targets. CONCLUSIONS: The findings suggest abnormalities in attentional "disengage" and "move" mechanisms in TS when directing attention to the right visual field, which may reflect left posterior parietal, superior colliculus, and midbrain pathology.     

Exposure with response prevention versus habit reversal in Tourettes's syndrome: a controlled study

The intentional nature of tics provides the opportunity to apply behavioural interventions aimed at tic reduction through interruption of stimulus-response sequences. The aim of this study has been to evaluate the effect of exposure and response prevention (ER) versus habit reversal (HR) in 43 Tourette's syndrome (TS) patients. The three outcome measures were: the Yale Global Tic Severity Scale (YGTSS), 15-min tic frequency registrations monitored at the institute and 15-min home tic frequency registrations. Both treatment conditions resulted in statistically significant improvements on all outcome measures (p < 0.001). No significant differences were found between the treatment conditions on any of the outcome measures, although there was a tendency in favour of ER on the YGTSS (p = 0.05). These results suggest that, at least in the short term, TS tic symptoms can be treated effectively with both types of treatment.     

Do obsessional beliefs discriminate OCD without tic patients from OCD with tic and Tourette's syndrome patients?

There is considerable overlap in symptomatology between Tourette's syndrome (TS) and obsessive-compulsive disorder (OCD). Increased rates of tics are found in OCD and up to 60% obsessive-compulsive symptoms in TS. However, in OCD obsessive-compulsive symptoms are more often anxiety-related and, as a consequence, aimed at anxiety-reduction, whereas in TS these symptoms are more stimulus-bound. Therefore, it is of clinical interest to study whether these phenomenological differences are reflected in differences between dysfunctional cognitions accompanying OC symptoms in OCD with or without tics and TS. Current cognitive theory of OCD ascertains that specific dysfunctional beliefs are important in the etiology and maintenance of OCD. To assess these beliefs, the obsessive-compulsive beliefs questionnaire-87 (OBQ-87) has been developed. In the present study, OBQ-87 scores of OCD patients without tics, OCD with tics, and TS (without OCD) patients were compared to those of normal controls. Results: OCD without tic patients exhibited higher OBQ-87 scores than TS patients. No differences were found between OCD with or without tic patients on any of the OBQ-87 subscales. These results suggest that: (1) dysfunctional beliefs have no discriminative power with respect to OCD with or without tic patients; (2) the direct relationship between types of OC symptoms and specific dysfunctional beliefs is questionable. Therefore, one can doubt the specificity of cognitive theory of OCD to explain specific OC behavior.     

Turner syndrome: a review of genetic and hormonal influences on neuropsychological functioning.

Turner syndrome (TS) is a genetic disorder affecting mainly females that arises from a loss of X chromosome material, most usually one of the two X chromosomes. TS is associated with a number of characteristic physical features such as short stature and absent ovaries as well as a set of common neuropsychological deficits and social and behavioral features. This paper will serve to review the cognitive, social, and psychoeducational abilities of individuals with TS as well as neuroimaging findings. Several putative genetic mechanisms contributing to their particular neurocognitive deficits will also be described including candidate genes. In addition, the available evidence on how hormones affect specific abilities in TS will be reviewed. It will be concluded that the TS neurobehavioral profile arises from an atypical cerebral organization caused by the complex interplay of insufficient expression of certain (unknown) genes on the X chromosome and by abnormal hormonal levels; however, it is still not clear exactly how the specific genes affect broader cognitive abilities. Future research needs to identify the elemental processes that are disturbed in TS and map these both to events in early brain development and subsequent brain function and to specific gene and hormonal contributions.     

Motor excitability is reduced prior to voluntary movements in children and adolescents with Tourette syndrome

Tourette syndrome (TS) is a neuro‐developmental disorder characterized by the occurrence of motor and vocal tics: involuntary, repetitive, stereotyped behaviours that occur with a limited duration, often typically many times in a single day. Previous studies suggest that children and adolescents with TS may undergo compensatory, neuroplastic changes in brain structure and function that help them gain control over their tics. In the current study we used single‐pulse and dual‐site paired‐pulse transcranial magnetic stimulation (TMS), in conjunction with a manual choice reaction time task that induces high levels of inter‐manual conflict, to investigate this conjecture in a group of children and adolescents with TS, but without co‐morbid Attention Deficit Hyperactivity Disorder (ADHD). We found that performance on the behavioural response‐conflict task did not differ between the adolescents with TS and a group of age‐matched typically developing individuals. By contrast, our study demonstrated that cortical excitability, as measured by TMS‐induced motor‐evoked potentials (MEPs), was significantly reduced in the TS group in the period immediately preceding a finger movement. This effect is interpreted as consistent with previous suggestions that the cortical hyper‐excitability that may give rise to tics in TS is actively suppressed by cognitive control mechanisms. Finally, we found no reliable evidence for altered patterns of functional inter‐hemispheric connectivity in TS. These results provide evidence for compensatory brain reorganization that may underlie the increased self‐regulation mechanisms that have been hypothesized to bring about the control of tics during adolescence.     

Implicit sequence learning in young people with Tourette syndrome with and without co-occurring attention-deficit/hyperactivity disorder

Impaired habit-learning has been proposed to underlie the tic symptoms of Tourette syndrome (TS). However, accounts differ in terms of how habit-learning is altered in TS, with some authors proposing habit formation is impaired due to a deficient ‘chunking’ mechanism, and others proposing habit-learning is overactive and tics reflect hyperlearned behaviours. Attention-deficit/hyperactivity disorder (ADHD) frequently co-occurs with TS and is known to affect cognitive function in young people with co-occurring TS and ADHD (TS + ADHD). It is unclear, however, how co-occurring ADHD symptoms affect habit-learning in TS. In this study, we investigated whether young people with TS would show deficient or hyperactive habit-learning, and assessed the effects of co-occurring ADHD symptoms on habit-learning in TS. Participants aged 9–17 years with TS (n = 18), TS + ADHD (n = 17), ADHD (n = 13), and typical development (n = 20) completed a motor sequence learning task to assess habit-learning. We used a 2 (TS-yes, TS-no) × 2 (ADHD-yes, ADHD-no) factorial analysis to test the effects of TS, ADHD, and their interaction on accuracy and reaction time indices of sequence learning. TS was associated with intact sequence learning, but a tendency for difficulty transitioning from sequenced to non-sequenced performance was suggestive of hyper-learning. ADHD was associated with significantly poorer accuracy during acquisition of the sequence, indicative of impaired habit-learning. There were no interactions between the TS and ADHD factors, indicating young people with TS + ADHD showed both TS- and ADHD-related atypicalities in habit-learning.     

Inhibition of Return in children with Tourette's syndrome and comorbid forms: A Preliminary Study

Background: This study investigated the nature and functioning of the visual-spatial inhibition of return (IOR) phenomenon in children with “pure” Tourette's syndrome (TS), and those with comorbid forms of TS. Method: Children with TS-only and “TS + comorbid” (TS + ADHD +/- OCD) and matched controls performed the inhibition of return (IOR) task, which involved responding to left and right visual targets appearing on a computer screen that were preceded by congruent or incongruent exogenous visual cues. Results: The TS-only group performed similarly on the IOR task to the controls. When the TS-only group was subdivided into children with mild and severe TS symptoms, a post hoc comparison between the controls and severe TS symptom children revealed that these TS children had a reduced magnitude of IOR for targets appearing in the right visual field. The comparison between the TS + comorbid and controls revealed an atypical IOR pattern for the TS + comorbid group. They displayed a loss of normal facilitatory and inhibitory effects for right visual field targets. Conclusions: The findings suggest abnormalities in attentional “disengage” and “move” mechanisms in TS when directing attention to the right visual field, which may reflect left posterior parietal, superior colliculus, and midbrain pathology.     

Features Resembling Tourette''s Syndrome in Developmental Stutterers

Developmental stuttering (DS) may be related to the extrapyramidal motor system and shares many clinical similarities with Tourette's syndrome (TS), which is widely believed to be associated with extrapyramidal dysfunction. Twenty-two stutterers were examined for neuropsychiatric features commonly seen in TS, including tics, obsessive-compulsive behaviors (OCB), and attention deficit disorders. Eleven stutterers displayed motor tics, and symptoms of OCB were observed at rates similar to those seen in persons with TS. Few stutterers demonstrated significant attentional deficits. Findings are consistent with models suggesting extrapyramidal involvement in DS and raise the possibility that DS and TS are pathogenetically related.     

The effects of co‐occurring ADHD symptoms on electrophysiological correlates of cognitive control in young people with Tourette syndrome

Efficient cognitive control is implicated in tic control in young people with Tourette syndrome (TS). Attention‐deficit/hyperactivity disorder (ADHD) frequently co‐occurs with TS and is associated with impaired cognitive control. Young people with TS and ADHD (TS+ADHD) show poorer cognitive control performance than those with TS, but how co‐occurring ADHD affects underlying neural activity is unknown. We investigated this issue by examining behavioural and event‐related potential (ERP) correlates of cognitive control in young people with these conditions. Participants aged 9–17 with TS (n = 17), TS+ADHD (n = 17), ADHD (n = 11), and unaffected controls (n = 20) performed a visual Go/Nogo task during electroencephalography (EEG) recording. Behavioural performance measures (D‐prime, RT, reaction time variability, post‐error slowing) and ERP measures (N2, P3, error‐related negativity (ERN), error positivity (Pe)) were analysed in a 2 (TS‐yes, TS‐no) × 2 (ADHD‐yes, ADHD‐no) factorial analysis to investigate the effects of TS, ADHD, and their interaction. The results of these analyses showed that ADHD was associated with poorer performance and reduced amplitude of all ERPs, reflecting widespread cognitive control impairments. Tourette syndrome was associated with slowed RTs, which might reflect a compensatory slowing of motor output to facilitate tic control. There was no interaction between the TS and ADHD factors for any behavioural or ERP measure, indicating the impairing effects of ADHD on behaviour and electrophysiological markers of cognitive control were present in TS+ADHD and that RT slowing associated with TS was unaffected by co‐occurring ADHD symptoms.     

Dilemmas in diagnosis and treatment of Gilles de la Tourette syndrome.

Gilles de la Tourette syndrome (TS) is a neurological disorder which has an inordinate risk of being diagnosed as psychogenic in nature because of commonly shared behavioral symptomes with syndromes of psychological origin. An overview of TS is presented including its history, symptomatology, and treatment of choice. The problems and pitfalls inherent in the diagnostic process which lead to psychogenic misconceptions are discussed. Treatment considerations include the secondary emotional problems and the negative consequences of the medication for TS. The implications for training professionals are discussed, but the essential point is that without an adequate history of the onset of symptoms, the potential for misdiagnosis is dramatically increased.     

Sensory sensitivity after acquired brain injury: A systematic review

Patients with acquired brain injury frequently report experiencing sensory stimuli as abnormally under- (sensory hyposensitivity) or overwhelming (sensory hypersensitivity). Although they can negatively impact daily functioning, these symptoms are poorly understood. To provide an overview of the current evidence on atypical sensory sensitivity after acquired brain injury, we conducted a systematic literature review. The primary aim of the review was to investigate the behavioural and neural mechanisms that are associated with self-reported sensory sensitivity. Studies were included when they studied sensory sensitivity in acquired brain injury populations, and excluded when they were not written in English, consisted of non-empirical research, did not study human subjects, studied pain, related sensory sensitivity to peripheral injury or studied patients with a neurodegenerative disorder, meningitis, encephalitis or a brain tumour. The Web of Science, PubMed and Scopus databases were searched for appropriate studies. A qualitative synthesis of the results of the 81 studies that were included suggests that abnormal sensory thresholds and a reduced information processing speed are candidate behavioural mechanisms of atypical subjective sensory sensitivity after acquired brain injury. Furthermore, there was evidence for an association between subjective sensory sensitivity and structural grey or white matter abnormalities, and to functional abnormalities in sensory cortices. However, further research is needed to explore the causation of atypical sensory sensitivity. In addition, there is a need for the development of adequate diagnostic tools. This can significantly advance the quantity and quality of research on the prevalence, aetiology, prognosis and treatment of these symptoms.     

Family Impact of Tourette's Syndrome

Tourette's syndrome (TS) is a neuropsychological disorder characterized by vocal and motor tics. TS is also associated with several behavior disorders such as Attention Deficit Hyperactivity Disorder, Oppositional Defiant Disorder, conduct disorder, and Obsessive-Compulsive Disorder. We examined the impact of Tourette's syndrome with and without comorbid psychiatric disorders on the family. TS complicated by comorbid disorders had a greater impact on the family than uncomplicated TS. Tourette's symptom severity was significantly correlated with the level of impact on the family and with the number of comorbid disorders. TS is a disorder with effects that extend beyond motor and vocal tics.     

What Do People Really Think of Me? Evaluating Bias in Interpersonal Predictions Over the Course of Cognitive-Behavioral Therapy of Depression

Cognitive behavioral therapy (CBT) of depression is hypothesized to achieve its effects by correcting negative biases. However, little research has tested how biases change over the course of CBT. We focus on biases in interpersonal judgments and examine whether changes in biases occur in CBT and are associated with symptom improvements. A sample of 126 adults (60% women, mean age 31.7, 83% White) participated in CBT of depression. Observers provided ratings of patients participating in two interpersonal tasks on three occasions. Patients were asked to predict observers’ ratings. In a thin slice (TS) task, observers evaluated how patients came across in a brief segment in which patients talked about themselves. In a Standard Interaction Task (SIT), observers rated the social skills patients displayed in challenging role plays. The difference between patient predictions and observer ratings provided measures of bias in these interpersonal judgments. TS and SIT bias became significantly less pessimistic and more realistic over the course of CBT. Improvements in TS bias were associated with a faster reduction in symptoms, whereas there was a non-significant trend for improvement in SIT bias being associated with faster symptom reduction. Consistent with the CBT model, negative interpersonal biases became more realistic throughout a course of CBT for depression and at least some of the changes in bias were related to therapeutic outcomes. We encourage future researchers to continue examining for whom and under which conditions correcting such biases produces the greatest benefits.     

Premonitory urges are associated with decreased grey matter thickness within the insula and sensorimotor cortex in young people with Tourette syndrome

Tourette syndrome (TS) is a neurological disorder characterized by vocal and motor tics and is associated with cortical–striatal–thalamic–cortical circuit (CSTC) dysfunction and hyperexcitability of cortical limbic and motor regions, which are thought to lead to the occurrence of tics. Importantly, individuals with TS often report that their tics are preceded by ‘premonitory sensory phenomena’ (PSP) that are described as uncomfortable cognitive or bodily sensations that precede the execution of a tic, and are experienced as a strong urge for motor discharge. While the precise role played by PSP in the occurrence of tics is controversial, PSP are nonetheless of considerable theoretical and clinical importance in TS, not least because they form the core component in many of the behavioural therapies that are currently used in the treatment of tic disorders. In this study, we investigated the brain structure correlates of PSP. Specifically, we conducted a whole‐brain analysis of cortical (grey matter) thickness in 29 children and young adults with TS and investigated the association between grey matter thickness and PSP. We demonstrate for the first time that PSP are inversely associated with grey matter thickness measurements within the insula and sensorimotor cortex. We also demonstrate that grey matter thickness is significantly reduced in these areas in individuals with TS relative to a closely age‐ and gender‐matched group of typically developing individuals and that PSP ratings are significantly correlated with tic severity.     

A qualitative study of the impact of living with neurofibromatosis type 2

Neurofibromatosis type 2 (Nf2) is an inherited autosomal dominant syndrome characterised by the development of nervous system tumours, ocular abnormalities and skin tumours. Symptoms of Nf2 can vary depending on the size and location of the tumour and include hearing loss, balance deficits and facial palsy. This study explored the physical, emotional and social impact of Nf2. Six patients were recruited through a neurofibromatosis clinic and underwent a semi-structured interview. Interviews were recorded and analysed using Framework analysis. Participants spoke of the negative impact of Nf2 on daily activities, including work. Social isolation resulted from the avoidance of social situations and was often a consequence of difficulties with communication due to loss of hearing. Patients expressed a range of negative emotional reactions in response to their diagnosis and the impact of the disease. Furthermore, the findings highlighted the important role of partners and family who were relied on for physical as well as emotional and psychological support. Patients also expressed frustration at the limited awareness of Nf2 among health professionals and a desire for improved access to information on Nf2 within their local community.     

Examining the neural antecedents of tics in Tourette syndrome using electroencephalography

Tourette syndrome (TS) is a neurodevelopmental disorder characterized by the occurrence of motor and vocal tics. TS is associated with cortical–striatal–thalamic–cortical circuit dysfunction and hyper-excitability of cortical limbic and motor regions that lead to the occurrence of tics. Importantly, individuals with TS often report that their tics are preceded by premonitory sensory/urge phenomena (PU) that are described as uncomfortable bodily sensations that precede the execution of a tic and are experienced as an urge for motor discharge. While tics are most often referred to as involuntary movements, it has been argued by some that tics should be viewed as voluntary movements that are executed in response to the presence of PU. To investigate this issue further, we conducted a study using electroencephalography (EEG). We recorded movement-related EEG (mu- and beta-band oscillations) during (1) the immediate period leading up to the execution of voluntary movements by a group of individuals with TS and a group of matched healthy control participants, and (2) the immediate period leading up to the execution of a tic in a group of individuals with TS. We demonstrate that movement-related mu and beta oscillations are not reliably observed prior to tics in individuals with TS. We interpret this effect as reflecting the greater involvement of a network of brain areas, including the insular and cingulate cortices, the basal ganglia and the cerebellum, in the generation of tics in TS. We also show that beta-band desynchronization does occur when individuals with TS initiate voluntary movements, but, in contrast to healthy controls, desynchronization of mu-band oscillations is not observed during the execution of voluntary movements for individuals with TS. We interpret this finding as reflecting a dysfunction of physiological inhibition in TS, thereby contributing to an impaired ability to suppress neuronal populations that may compete with movement preparation processes.     

Cerebral laterality in Turner syndrome: a critical review of the literature.

Turner syndrome (TS) is a genetic disorder in females characterized by the complete or partial absence of one X chromosome. Its most consistent physical features include short stature and ovarian dysgenesis. TS individuals demonstrate a characteristic neurocognitive profile involving weaknesses in visuospatial processing. The hypothesis of defective right hemisphere specialization has been offered to explain the visuospatial deficits in TS. In contrast, an alternative explanation proposes a more uniform dysfunction of the left and right hemispheres, based on findings of symmetrical abnormalities. This article presents an overview of the two hypotheses, along with relevant findings on hemispheric specialization with respect to TS. The impact of the genetic and hormonal mechanisms on the neurocognitive profile of TS is also discussed and directions for further empirical research are identified.