Obsessive-compulsive disorder: boundary issues

The boundaries between obsessive-compulsive disorder (OCD) and other neuropsychiatric disorders remain unresolved and may well differ from one disorder to another. Endophenotypes are heritable, quantitative traits hypothesized to more closely represent genetic risk for complex polygenic mental disorders than overt symptoms and behaviors. They may have a role in identifying how closely these disorders are associated with another and with other mental disorders with which they share major comorbidity. This review maps the nosological relationships of OCD to other neuropsychiatric disorders, using OCD as the prototype disorder and endophenotype markers, such as cognitive, imaging, and molecular data as well as results from demographic, comorbidity, family, and treatment studies. Despite high comorbidity rates, emerging evidence suggests substantial endophenotypic differences between OCD and anxiety disorders, depression, schizophrenia, and addictions, though comparative data is lacking and the picture is far from clear. On the other hand, strong relationships between OCD, Tourette syndrome, body dysmorphic disorder, hypochondriasis, grooming disorders, obsessive-compulsive personality disorder, and pediatric autoimmune neuropsychiatric disorders associated with streptococcus are likely. Studies designed to delineate the cause, consequences, and common factors are a challenging but essential goal for future research in this area.     

Obsessive-compulsive symptoms in eating disorders

Obsessive-compulsive symptoms were measured in a consecutive series of new referrals with anorexia nervosa (n = 29) and bulimia nervosa (n = 77). In contrast with previous reports, there was no significant difference on MOCI scores between eating disorder groups and normal controls. A consecutive series of 38 patients with bulimia nervosa then entered a structured treatment programme. Poor outcome cases had a higher score on the MOCI-doubting sub-scale. However, there was no significant difference in obsessive-compulsive scores between those who were binge-free and those who were bingeing daily at the end of treatment and there was no significant in outcome between high and low-scorers on the MOCI. This study fails to support the view that the eating disorders are a subtype of OCD. Previous conflicting results are attributed to selection bias and the effects of low body weight.     

Obsessive-compulsive disorder, anxiety disorders, and self-esteem: an exploratory study.

In a preliminary investigation of the link between self-esteem and obsessional problems, patients with OCD were compared with people suffering from other anxiety disorders and non-anxious controls. A questionnaire was devised which allowed the reliable coding of open ended responses focussed on issues surrounding self-worth; standardized measures of self-esteem and clinical symptomatology were also administered. Results indicated that both clinical groups differed significantly from non-clinical controls on generalized self-esteem assessments. There was some evidence of OCD specific effects; obsessionals were more likely than anxious controls to link their self-worth to other people and their relationships. They also regarded the possibility of causing harm as likely to result in other people making extreme negative and critical judgements of them; the other groups expected the responses of others towards them to be more lenient. The implications for future research and for treatment of OCD are discussed.     

Pathological gambling and obsessive-compulsive spectrum disorders

To test the hypothesis that pathological gambling can be classified as an Obsessive-Compulsive Spectrum Disorder, the Padua Inventory was administered to 40 diagnosed pathological gamblers and a control group of 40 normal subjects. Analysis showed that the pathological gamblers obtained a significantly higher mean total score on obsessionality than controls. Elevated scores on two factors reflecting impaired control of mental activities and loss of motor control contributed to the over-all difference. In the context of other research suggesting pathological gamblers would score high on psychometric measures of impulsivity, this study provides preliminary support for a Spectrum Disorder Model, suggesting that pathological gamblers are characterised by elevated scores on traits of 'impulsivity' and 'obsessionality.'     

Genetics of autism spectrum disorders

Characterized by a combination of abnormalities in language, social cognition and mental flexibility, autism is not a single disorder but a neurodevelopmental syndrome commonly referred to as autism spectrum disorder (ASD). Several dozen ASD susceptibility genes have been identified in the past decade, collectively accounting for 10-20% of ASD cases. These findings, although demonstrating that ASD is etiologically heterogeneous, provide important clues about its pathophysiology. Diverse genetic and genomic approaches provide evidence converging on disruption of key biological pathways, many of which are also implicated in other allied neurodevelopmental disorders. Knowing the genes involved in ASD provides us with a crucial tool to probe both the specificity of ASD and the shared neurobiological and cognitive features across what are considered clinically distinct disorders, with the goal of linking gene to brain circuits to cognitive function.     

Olfaction in autism spectrum disorders: A systematic review

Olfactory function is a well-known early biomarker for neurodegeneration and neural functioning in the adult population, being supported by a number of brain structures that could be dysfunctioning in neurodegenerative processes. Evidence has suggested that atypical sensory and, particularly, olfactory processing is present in several neurodevelopmental conditions, including autism spectrum disorders (ASDs). In this paper, we present data obtained by a systematic literature review, conducted according to PRISMA guidelines, regarding the possible association between olfaction and ASDs, and analyze them critically in order to evaluate the occurrence of olfactory impairment in ASDs, as well as the possible usefulness of olfactory evaluation in such conditions. The results obtained in this analysis suggested a possible involvement of olfactory impairment in ASDs, underlining the importance of olfactory evaluation in the clinical assessment of ASDs. This assessment could be potentially included as a complementary evaluation in the diagnostic protocol of the condition. Methods for study selection and inclusion criteria were specified in advance and documented in PROSPERO protocol #CRD42014013939.     

Novel treatments for autistic spectrum disorders

In no area of developmental pediatric practice is there more controversy regarding the choice of treatment than related to children with autistic spectrum disorders (ASD). Complementary and alternative medical therapies (CAM) are often elected because they are perceived as treating the cause of symptoms rather than the symptoms themselves. CAM used for autism can be divided by proposed mechanism: immune modulation, gastrointestinal, supplements that affect neurotransmitter function, and nonbiologic intervention. Secretin as a therapy for autism is discussed as an example of how a clinical observation rapidly grew to a widespread treatment before well-designed studies demonstrated absence of effect. The plausibility for behavioral effect was not substantiated by clinical studies. CAM used for treatment of autism is examined in terms of rationale, evidence of efficacy, side effects, and additional commentary. Families and clinicians need access to well-designed clinical evidence to assist them in choice of therapies.     

自闭症谱系障碍个体的注意解离

注意解离是注意定向网络的重要组成部分, 指在注意转移过程中对原来刺激进行注意分离的过程。自闭症个体注意解离的早期受损会直接影响其它重要功能的发展, 尤其是唤醒调节和共同注意发展。采用间隙重叠范式的研究发现, 自闭症个体注意解离能力是否异常还存在争议, 被试年龄及取样、测量指标和刺激特征可能是影响的因素; 其神经机制可能涉及额叶、顶叶、小脑和胼胝体等脑区。未来应从脑机制研究入手, 综合考虑被试特征、研究方法和刺激特征对注意解离结果的影响, 明确其在自闭症早期预测和识别中的作用。     

Developmental regression in autism spectrum disorders

The occurrence of developmental regression in autism is one of the more puzzling features of this disorder. Although several studies have documented the validity of parental reports of regression using home videos, accumulating data suggest that most children who demonstrate regression also demonstrated previous, subtle, developmental differences. Counter to clinical intuition, the earlier development of social, language, and attachment behaviors followed by regression does not seem to support later recovery of skills or better developmental outcomes compared to children who never had speech or typical social responsivity. In fact, this regressive group may have somewhat greater developmental impairment than the nonregressive group, though the two groups do not appear to present different behavioral phenotypes. Although autism is not the only condition in which regression occurs, it appears to be the most frequent condition. Other disorders that demonstrate an early regression with no known etiology include total blindness from birth and childhood disintegrative disorder, both of which demonstrate behavioral relations to autism. In addition, two biological conditions with known etiologies also involve regression with some behaviors resembling autism behavioral phenotype: Rett syndrome (a genetic disorder; see Glaze, this issue) and Landau-Kleffner syndrome (see McVicar and Shinnar, this issue), which involves a seizure disorder.     

自闭症谱系障碍的生物基础

自闭症谱系障碍是一组发病于生命早期, 由一系列生理、心理因素引起的神经发育障碍。遗传、脑神经结构、营养素等是自闭症谱系障碍的生物基础的重要来源。个体在孕育早期形成的大脑和机体异常可能是导致自闭症谱系障碍的关键。这种异常在出生后的发育中具体作用于神经活动、脑发育、免疫系统等生理途径。研究者们今后可以尝试横跨不同自闭症谱系障碍亚型、年龄和发育阶段, 开展横向与纵向相结合的大范围研究, 以进一步明确自闭症谱系障碍的生物基础。     

Deconstructing Frith and Snowling's homograph-reading task: Implications for autism spectrum disorders

The poor performance of autistic individuals on a test of homograph reading is widely interpreted as evidence for a reduction in sensitivity to context termed “weak central coherence”. To better understand the cognitive processes involved in completing the homograph-reading task, we monitored the eye movements of nonautistic adults as they completed the task. Using single trial analysis, we determined that the time between fixating and producing the homograph (eye-to-voice span) increased significantly across the experiment and predicted accuracy of homograph pronunciation, suggesting that participants adapted their reading strategy to minimize pronunciation errors. Additionally, we found evidence for interference from previous trials involving the same homograph. This progressively reduced the initial advantage for dominant homograph pronunciations as the experiment progressed. Our results identify several additional factors that contribute to performance on the homograph reading task and may help to reconcile the findings of poor performance on the test with contradictory findings from other studies using different measures of context sensitivity in autism. The results also undermine some of the broader theoretical inferences that have been drawn from studies of autism using the homograph task. Finally, we suggest that this approach to task deconstruction might have wider applications in experimental psychology.     

Perceptual organization in schizophrenia spectrum disorders: empirical research and theoretical implications

The research into perceptual organization in schizophrenia spectrum disorders has found evidence for and against a perceptual organization deficit and has interpreted the data from within several different theoretical frameworks. A synthesis of this evidence, however, reveals that this body of work has produced reliable evidence for deficits in schizophrenia, as well as for the clinical, stimulus, and task parameters associated with normal and abnormal performance. Recent models of cognition have also advanced understanding of the underlying pathophysiological processes of perceptual organization dysfunction in schizophrenia spectrum disorders. These suggest that deficits in perceptual organization may be one manifestation of a wider disturbance in the integration of contextually related information across space and time.     

Obsessive-compulsive disorder: beyond segregated cortico-striatal pathways

Obsessive-compulsive disorder (OCD) affects approximately 2-3% of the population and is characterized by recurrent intrusive thoughts (obsessions) and repetitive behaviors or mental acts (compulsions), typically performed in response to obsessions or related anxiety. In the past few decades, the prevailing models of OCD pathophysiology have focused on cortico-striatal circuitry. More recent neuroimaging evidence, however, points to critical involvement of the lateral and medial orbitofrontal cortices, the dorsal anterior cingulate cortex and amygdalo-cortical circuitry, in addition to cortico-striatal circuitry, in the pathophysiology of the disorder. In this review, we elaborate proposed features of OCD pathophysiology beyond the classic parallel cortico-striatal pathways and argue that this evidence suggests that fear extinction, in addition to behavioral inhibition, is impaired in OCD.     

Religion and suicide acceptability: a cross-national analysis

Four perspectives (moral community thesis, religious integration, religious commitment, and social networks) guide the selection of variables in this study. Data are from the combined World Values/European Values Surveys for 2000 (50,547 individuals nested in 56 nations). The results of a multivariate hierarchical linear model support all four perspectives. Persons residing in nations with relatively high levels of religiosity, who are affiliated with one of four major faiths, are religiously committed, and are engaged with a religious network are found to be lower in suicide acceptability. The religious integration perspective, in particular, is empirically supported; affiliation with Islam is associated with low suicide acceptability. The findings provide strong support for an integrated model and demonstrate the usefulness of the moral community thesis in understanding suicide acceptability.