Differences in neuropsychological performance between subtypes of obsessive-compulsive disorder

The relationship between cognitive phenotypes of compulsivity and impulsivity and clinical variables in obsessive-compulsive disorder: A systematic review and Meta-analysis

BACKGROUND

This systematic review and meta-analysis explored the relationship between cognitive phenotypes of compulsivity and impulsivity and clinical variables in obsessive-compulsive disorder (OCD).

METHODS

We searched Pubmed, Scopus, Cochrane Library and PsychINFO databases until February 2023 for studies comparing patients with OCD and healthy controls on cognitive tests of compulsivity and impulsivity. The study followed PRISMA guidelines and was pre-registered on PROSPERO (CRD42021299017).

RESULTS

Meta-analyses of 112 studies involving 8313 participants (4289 patients with OCD and 4024 healthy controls) identified significant impairments in compulsivity (g = -0.58, [95%CI -0.68, -0.47]; k = 76) and impulsivity (g = -0.48, [95%CI -0.57, -0.38]; k = 63); no significant difference between impairments. Medication use and comorbid psychiatric disorders were not significantly related to impairments. No associations were revealed with OCD severity, depression/anxiety, or illness duration.

CONCLUSION

Cognitive phenotypes of compulsivity and impulsivity in patients with OCD appear to be orthogonal to clinical variables, including severity of OCD symptomatology. Their clinical impact is poorly understood and may require different clinical assessment tools and interventions.

Executive functioning in body dysmorphic disorder and obsessive-compulsive disorder

OBJECTIVE

To assess executive functions (EFs) in patients with body dysmorphic disorder (BDD) and obsessive-compulsive disorder (OCD) compared with healthy controls.

METHODS

Adults diagnosed with BDD (n = 26) or OCD (n = 29) according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, and healthy controls (n = 28) underwent validated and computerized neuropsychological tests, spatial working memory (SWM), intra-extra-dimensional set shifting (IED), and stop signal task (SST), from the Cambridge Neuropsychological Test Automated Battery (CANTAB). Test performance was compared between groups, and correlated with standardized symptom severity of BDD and OCD. Significance level was set to P < .05.

RESULTS

There were no statistically significant between-group differences on key outcome measures in SWM, IED, or SST. There was a weak positive correlation between symptom severity and test errors on SWM and IED in both OCD and BDD groups; increased clinical severity was associated with more errors in these tests. Furthermore, there was a negative correlation between symptom severity and SST in the BDD group.

CONCLUSIONS

Patients with BDD or OCD did not differ from healthy control subjects in terms of test performance; however, there were several statistically significant correlations between symptom severity and performance in those with BDD or OCD. More studies on EFs in BDD and OCD are required to elucidate if there are differences in EFs between these two disorders.

Efficacy and tolerability of pharmacotherapy for obsessive-compulsive personality disorder: a systematic review of randomized controlled trials

INTRODUCTION

Although obsessive-compulsive personality disorder (OCPD) is one of the most prevalent personality disorders, it is one of the least studied. There is debate as to whether pharmacotherapy is efficacious for OCPD. We aimed to systematically evaluate the efficacy and tolerability of pharmacotherapy for OCPD.

AREAS COVERED

This systematic review found two randomized controlled trials investigating pharmacotherapy of OCPD. In a study of major depression (n = 308) with comorbid OCPD (n = 71), citalopram was more effective for OCPD than sertraline with fewer drop-outs from treatment. In a small study of OCPD (n = 24), fluvoxamine was more effective than placebo, and there was a low drop-out rate. Risk of bias and quality assessment of these studies was not possible, and findings have very low levels of certainty.

EXPERT OPINION

Two studies provide preliminary evidence in support of citalopram and fluvoxamine for OCPD. Further randomized controlled trials are required before firm conclusions can be drawn regarding efficacy of pharmacotherapy for OCPD.

Visuospatial working memory capacity moderates the relationship between anxiety and OCD related checking behaviors

BACKGROUND

Compulsive checking behavior is the most prevalent compulsive behavior in patients with obsessive-compulsive disorder (OCD). While some studies have shown that anxiety and executive function influence compulsive checking behavior, the relationship between these constructs is inconclusive. Hence, we sought to explore the interplay between executive function, anxiety and compulsive checking behavior.

MATERIALS AND METHODS

47 healthy participants (HC) and 51 patients with OCD participated in the study. Symptoms and emotional states were assessed using the Yale-Brown Obsessive Compulsive Scale, the Obsessive-Compulsive Inventory-Revised, the Beck Anxiety Inventory, and the Beck Depression Inventory. Participants also completed three tests of neuropsychological functioning: the Stop Signal Task, the Spatial working memory Task, and the Wisconsin card sorting test. We analyzed the relationships between anxiety, executive function, and compulsive checking symptoms.

RESULTS

Patients with OCD showed significantly greater anxiety (p < 0.001) and impairments in visuospatial working memory function (p = 0.030) compared to HC participants, while inhibition and set-shifting were not significantly different between the two groups. Visuospatial working memory was negatively related to compulsive checking behavior (p = 0.016). Visuospatial working memory also played a moderating role in the positive relationship between anxiety and compulsive checking behavior (β = -0.281, p = 0.022).

CONCLUSION

Anxiety symptoms play an important role in explaining compulsive checking behavior in patients with OCD who have relatively weak visuospatial working memory ability. These findings provide a foundation for further research regarding the roles of emotion and cognitive inflexibility in compulsive checking behavior in patients with OCD.

Comparative Clinical and Neuropsychological Characteristics in Schizophrenia and Schizophrenia-Obsessive-Compulsive Disorder Patients

ABSTRACT

The present study aimed to compare neuropsychological characteristics of patients with schizophrenia and patients with schizophrenia-obsessive-compulsive disorder (OCD). A total of 78 patients were included in the study, with 32 patients diagnosed with schizophrenia and 46 patients diagnosed with schizophrenia-OCD according to the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition criteria. Two groups of the patients were compared with each other in terms of demographic data, psychotic symptoms, and clinical and neuropsychological characteristics. In this study, the schizophrenia-OCD relationship was seen at a higher rate in male patients, and this group has worse clinical features. In addition, there was no significant difference among sociodemographics, clinical characteristics, and social and neuropsychological functionality between the two groups. According to our results, patients with schizophrenia-OCD experience more depression and anxiety that are related to poorer quality of life. Longitudinal and more homogeneous patient groups are needed for further studies to reveal whether schizophrenia accompanied by OCD is a comorbidity, a subtype of schizophrenia, or a different disorder.

Executive Functioning and Clinical Variables in Patients with Obsessive-Compulsive Disorder

Background: Cognitive flexibility, response inhibition, and working memory are considered the main mechanisms responsible for executive control. This study examined differences in cognitive flexibility, inhibition, and working memory in patients with obsessive–compulsive disorder (OCD) relative to a control group. Method: A total of 62 obsessive-compulsive participants (OCD = 32; healthy control = 32) aged between 17 and 56 years old (M = 33.16, SD = 9.23) were administered the computerized Wisconsin Card Sorting Test, Stroop Color–Word Test, Go/No-Go Task, Digit Test, and Corsi Block Test. Clinician-rated and self-reported obsessive–compulsive symptom severity, and anxiety, depression, and obsessive beliefs were evaluated. Results: The control group performed better than the OCD group in tasks involving cognitive flexibility, inhibition, and visuospatial working memory. Anxiety and obsessive beliefs influenced the participants’ performance on inhibition and working memory tasks. Similarly, comorbidity also influenced inhibition and working memory. In addition, the use of pharmacotherapy and the degree of OCD symptom severity influenced verbal working memory. Conclusions: Cognitive flexibility, inhibition, and visuospatial working memory deficits may be endophenotypes of OCD but require further examination for specificity. OCD severity, comorbidity patterns, anxiety, and obsessive beliefs may influence performance.

A cross-species assessment of behavioral flexibility in compulsive disorders

Lack of behavioral flexibility has been proposed as one underlying cause of compulsions, defined as repetitive behaviors performed through rigid rituals. However, experimental evidence has proven inconsistent across human and animal models of compulsive-like behavior. In the present study, applying a similarly-designed reversal learning task in two different species, which share a common symptom of compulsivity (human OCD patients and Sapap3 KO mice), we found no consistent link between compulsive behaviors and lack of behavioral flexibility. However, we showed that a distinct subgroup of compulsive individuals of both species exhibit a behavioral flexibility deficit in reversal learning. This deficit was not due to perseverative, rigid behaviors as commonly hypothesized, but rather due to an increase in response lability. These cross-species results highlight the necessity to consider the heterogeneity of cognitive deficits in compulsive disorders and call for reconsidering the role of behavioral flexibility in the aetiology of compulsive behaviors.

Cognitive Inflexibility in OCD and Related Disorders

Cognitive inflexibility is suggested by the hallmark symptoms of obsessive-compulsive disorder (OCD), namely the occurrence of repetitive thoughts and/or behaviours that persist despite being functionally impairing and egodystonic to the individual. As well as being implied by the top-level symptoms, cognitive inflexibility in OCD, and some related conditions, has also been objectively quantified in case-control studies using computerised cognitive tasks. This chapter begins by considering the objective measurement of different aspects of cognitive flexibility using neuropsychological paradigms, with a focus on neural and neurochemical substrates. It moves on to conduct a systematic review and meta-analysis of findings from a widely deployed flexibility task: the Intra-Dimensional/Extra-Dimensional Set-Shift Task (IDED). By pooling data from 11 studies (335 OCD patients and 311 controls), we show that Extra-Dimensional (ED) shift deficits are a robust and reproducible finding (effect size medium-large) in OCD across the literature, and that this deficit is not attributable to group differences in age or IQ. The OCD ED deficit is then discussed in terms of dysfunction of fronto-striatal pathways (as exemplified, for example, by functional connectivity data), and the putative role of different neurotransmitters. We consider evidence that impaired ED shifting constitutes a candidate vulnerability marker (or 'endophenotype') for OCD. The available literature is then surveyed as to ED findings in other obsessive-compulsive (OC) related disorders (e.g. hoarding, body-dysmorphic disorder, and trichotillomania), as well as in non-OC disorders (schizophrenia and anxiety symptoms in general). Lastly, we consider more recent, emerging developments in the quantification of compulsivity using cognitive tasks and questionnaires, as well as key directions for future research, including the need to refine compulsivity and its composite cognitive processes.

Mental Fatigue, But Not other Fatigue Characteristics, as a Candidate Feature of Obsessive Compulsive Personality Disorder in Patients with Anxiety and Mood Disorders-An Exploratory Study

BACKGROUND

Obsessive compulsive personality disorder (OCPD) is commonly associated with anxiety and mood disorders (AMDs), in which fatigue and executive dysfunction represent key symptoms. Executive dysfunction has also been demonstrated in subjects with OCPD, and is additionally found to be a cardinal feature of fatigue. This study aimed to investigate the associations between fatigue, executive dysfunction, and OCPD in patients with AMDs.

METHODS

In this cross-sectional study, 85 AMD patients (78% females, mean age 39 ± 11 years) were evaluated for OCPD traits by using the observer-rated Compulsive Personality Assessment Scale. The Multidimensional Fatigue Inventory-20 was used to measure different aspects of fatigue, and the Trail Making Test was employed to assess executive functioning. The Hamilton rating scales were used to evaluate anxiety and depression symptoms.

RESULTS

Controlling for potential confounders, there was a significant link between OCPD and mental fatigue (OR, 1.27; 95% CI, 1.02 to 1.58; p = 0.033). No associations were found between the presence of OCPD and other relevant fatigue characteristics, including general fatigue, physical fatigue, reduced activity, and reduced motivation, as well as executive functions.

CONCLUSIONS

To the best of our knowledge, this study is the first to report associations between OCPD and mental fatigue in patients with AMDs, suggesting mental fatigue as a clinically important symptom when considering particular personality pathologies.

Neuropsychological performance across symptom dimensions of obsessive-compulsive disorder: a comment on the state and critical review of the literature

Introduction: Obsessive-compulsive disorder (OCD) is a heterogeneous disorder, with multiple symptom presentations. Delineating the neuropsychological characteristics associated with previously identified symptom clusters may therefore be useful in assisting to better define symptom subtypes of OCD.Areas covered: This review summarizes the existing literature on the assessment of neuropsychological performance in symptom-based dimensions of OCD. Results of 23 studies are described and the methodological issues and challenges present in this body of literature are discussed.Expert opinion: The current state of the literature precludes a meaningful meta-analysis of cognitive dysfunction across the breadth of symptom dimensions of OCD. This is due primarily to significant methodological differences observed between studies, both in terms of neuropsychological measures and symptom subtyping methods employed, and any resulting meta-analytic results would be biased by varying quality of evidence. Future studies addressing these limitations should include more consistent neuropsychology measures and methods of classifying OCD symptoms with the aim of reproducing the results of previous research to identify more concrete patterns of neuropsychological performance across dimensions; best practices and alternative approaches are discussed.

Functional connectivity within the salience network differentiates autogenous- from reactive-type obsessive-compulsive disorder

BACKGROUND

Obsessive-compulsive disorder (OCD) is a clinically heterogeneous condition. To better understand and treat patients, symptomatology of OCD has been categorized into more homogenous symptom dimensions. The autogenous-reactive classification model has proven helpful in the elucidation of the neurobiological substrates for clinical heterogeneity in OCD. The purpose of the current study was to systematically compare regional and network functional alterations between OCD subtypes based on the autogenous-reactive model.

METHODS

Autogenous-type OCD patients (OCD-AO, n = 40), reactive-type patients (OCD-RO, n = 42), and healthy controls (HC, n = 70) underwent functional magnetic resonance imaging (fMRI) scans. The amplitude of low-frequency fluctuation (ALFF) and regional homogeneity (ReHo) were compared among subjects. Areas of abnormal local spontaneous brain activity that differentiated OCD-AO and OCD-RO patients were identified and entered as seeds in functional connectivity (FC) analysis.

RESULTS

Compared to OCD-RO patients and HC participants, OCD-AO patients showed increased ALFF in the left anterior insula (AI), increased ReHo in the right AI, and hyperconnectivity between bilateral AI and anterior cingulate cortex (ACC). Both OCD-AO and OCD-RO patients shared regional function deficits in several areas within the prefrontal cortex, and stronger FC between bilateral AI and major nodes of the default mode network (DMN) compared to healthy controls.

CONCLUSION

The current results suggest that aberrant functional interaction between the salience network (SN) and the DMN may represent a common substrate in the pathophysiology of OCD, while impaired functional coupling within the SN is distinct to autogenous-type OCD patients. These findings provide further neurobiological evidence to support the autogenous-reactive classification model and contribute to the understanding of the neurobiological basis for clinical heterogeneity in OCD.

Btbd3 expression regulates compulsive-like and exploratory behaviors in mice

BTB/POZ domain-containing 3 (BTBD3) was identified as a potential risk gene in the first genome-wide association study of obsessive-compulsive disorder (OCD). BTBD3 is a putative transcription factor implicated in dendritic pruning in developing primary sensory cortices. We assessed whether BTBD3 also regulates neural circuit formation within limbic cortico-striato-thalamo-cortical circuits and behaviors related to OCD in mice. Behavioral phenotypes associated with OCD that are measurable in animals include compulsive-like behaviors and reduced exploration. We tested Btbd3 wild-type, heterozygous, and knockout mice for compulsive-like behaviors including cage-mate barbering, excessive wheel-running, repetitive locomotor patterns, and reduced goal-directed behavior in the probabilistic learning task (PLT), and for exploratory behavior in the open field, digging, and marble-burying tests. Btbd3 heterozygous and knockout mice showed excessive barbering, wheel-running, impaired goal-directed behavior in the PLT, and reduced exploration. Further, chronic treatment with fluoxetine, but not desipramine, reduced barbering in Btbd3 wild-type and heterozygous, but not knockout mice. In contrast, Btbd3 expression did not alter anxiety-like, depression-like, or sensorimotor behaviors. We also quantified dendritic morphology within anterior cingulate cortex, mediodorsal thalamus, and hippocampus, regions of high Btbd3 expression. Surprisingly, Btbd3 knockout mice only showed modest increases in spine density in the anterior cingulate, while dendritic morphology was unaltered elsewhere. Finally, we virally knocked down Btbd3 expression in whole, or just dorsal, hippocampus during neonatal development and assessed behavior during adulthood. Whole, but not dorsal, hippocampal Btbd3 knockdown recapitulated Btbd3 knockout phenotypes. Our findings reveal that hippocampal Btbd3 expression selectively modulates compulsive-like and exploratory behavior.

Cognitive Process in Patients With Obsessive-Compulsive Disorder: A Cross-Sectional Analytic Study

Introduction:

In recent studies, deficit in cognitive process has been investigated as one of the etiological hypotheses in a wide range of Obsessive-Compulsive Disorder (OCD). This research aimed to compare cognitive process in patients with OCD and healthy groups.

Methods:

In the current cross-sectional analytic study, 43 patients with OCD and 43 healthy individuals matched with gender, age, educational and marital status were selected by convenience sampling method and assessed by Wisconsin Cart Sorting Test (WCST), Paced Auditory Serial Addition Test (PASAT) and Yale-Brown Obsessive Compulsive Scale (Y-BOCS). The obtained data were analyzed with Chi-square, Independent t test, Mann-Whitney U test and Pearson correlation in SPSS version16.

Results:

There was no difference between the patients with OCD and the healthy group in demographic characteristics (P>0.05). There was a significant differences between two group on the all subscale of WCST test and PASAT3, PASAT2 tests (P<0.01). These findings indicate that the OCD patient’s performance in cognitive process was significantly worse than the healthy controls.

Conclusion:

The findings indicate that individuals with OCD suffer from a deficiency in various aspects of cognitive processes. Therefore, paying attention to these deficiencies can make an important contribution to the treatment of these patients.

Neurocognitive deficits in obsessive-compulsive disorder: A selective review

Obsessive-compulsive disorder (OCD) is a debilitating mental illness characterized by an early onset and chronic course. Evidence from several lines of research suggests significant neuropsychological deficits in patients with OCD; executive dysfunction and nonverbal memory deficits have been reported consistently in OCD. These deficits persist despite controlling potential confounders such as comorbidity, severity of illness, and medications. Neuropsychological impairments are independent of illness severity, thus suggesting that the neuropsychological deficits are trait markers of the disease. In addition, these deficits are seen in first-degree relatives of individuals with OCD. These reports suggest that neuropsychological deficits are potential endophenotype markers in OCD. Neuropsychological studies in pediatric OCD are limited; they show impairments of small effect size across multiple domains but with doubtful clinical significance. Preliminary evidence shows that different symptom dimensions of OCD may have unique neuropsychological deficits suggestive of discrete but overlapping neuroanatomical regions for individual symptom dimensions. Overall, neuropsychological deficits further support the role of frontostriatal circuits in the neurobiology of OCD. In addition, emerging literature also suggests the important role of other areas, in particular parietal cortex. Preliminary evidence suggests the possible role of neuropsychological deficits to be markers of treatment response but needs to be examined in future. Longitudinal studies with examination of patients at different time points and examination of their potential utility as predictors of treatment response are needed in future.

The role of spatial store and executive strategy in spatial working memory: a comparison between patients with obsessive-compulsive disorder and controls

INTRODUCTION

Patients with obsessive-compulsive disorder (OCD) showed impaired spatial working memory (SWM). We evaluated whether patients and healthy controls (HCs) differed in spatial store capacity, and whether they differed in the relative weight of spatial store capacity and/or executive strategy in SWM.

METHODS

Thirty inpatients with OCD and 31 age- and education-matched HCs underwent the CANTAB SWM, SRM (a measure of spatial store). The severity of OC symptoms was assessed using the Y-BOCS. Statistical significance: α = 0.05.

RESULTS

Patients showed poorer performance than HCs in all neuropsychological outcomes. Both poorer SRM and SWM strategy were significantly associated with poorer SWM in the entire sample. No significant interaction between SRM and Group was found, while a significant interaction between SWM strategy and Group emerged; in patients the magnitude of this association was approximately twofold larger than in HCs. OC symptom severity did not correlate with neuropsychological performance.

CONCLUSIONS

Patients with OCD had poorer spatial store capacity than HCs. However, the weight of poorer executive strategy in SWM was greater in patients than HCs, whereas the weight of spatial store was similar. We provided a direct evidence that an impairment in the executive component might be the crucial factor influencing the poorer SWM of these patients.

Novel Smartphone Interventions Improve Cognitive Flexibility and Obsessive-Compulsive Disorder Symptoms in Individuals with Contamination Fears

One type of obsessive-compulsive disorder (OCD) is characterized by contamination fears and compulsive cleansing. Few effective treatments are available for this debilitating condition. Compulsive symptoms, such as excessive washing, are believed to be mediated by cognitive inflexibility-arguably the most striking cognitive impairment in OCD. In this study, we investigated the effects of two novel smartphone interventions on cognitive flexibility and OCD symptoms in healthy individuals with OCD-like contamination fears. In the first intervention, participants watched a brief video recording of themselves engaging in handwashing on a smartphone, four times a day, for a total of one week (N = 31). The second intervention was similar except that participants watched themselves repeatedly touching a disgust-inducing object (N = 31). In a third (control) "intervention", participants watched themselves performing sequential hand movements (N = 31). As hypothesized, the two smartphone interventions, unlike the control, improved cognitive flexibility; as assessed on the Intradimensional-Extradimensional Set Shifting task (a sensitive marker of cognitive flexibility). The two interventions, unlike the control, also improved OCD symptoms (measured with the Obsessive-Compulsive Inventory-Revised and Yale-Brown Obsessive-Compulsive Scale). Finally, we found high levels of adherence to the interventions. These findings have significant clinical implications for OCD.

The impact of symptom severity on cognitive function in obsessive-compulsive disorder: A meta-analysis

Research on cognitive functions in obsessive-compulsive disorder (OCD) is notoriously heterogeneous with no moderators identified that account for this variability. OCD severity is the primary potential moderator of interest given the longstanding trait versus state debate. Nevertheless, severity has been previously assessed exclusively as a moderator and was not directly and systematically investigated. To address this gap in the literature, the aim of this study was to conduct a systematic meta-analytic review of correlations between cognitive function and symptom severity in OCD samples. Thirty-eight studies were included, allowing for analysis of 132 effects and meta-regression analyses for potential moderators. Small effects were found for the association between cognitive function and symptom severity on major neuropsychological domains, and some subdomains exhibited medium effects for this association. However, several significant methodological and conceptual problems were identified, including the use of the Yale-Brown Obsessive-Compulsive Scale that assesses severity in the past week and not at time of testing, a tendency to not report non-significant correlations, and problematic ecological validity of neuropsychological tests in OCD. In conclusion, we found a small-to-moderate degree of association between OCD symptom severity and cognitive function, but results should be interpreted cautiously given the limitations identified. We offer recommendations that will facilitate future research into this association and move the field beyond the largely stagnant debate about the state versus trait nature of cognitive functioning in OCD, and across disorders.

Planning functioning and impulsiveness in obsessive-compulsive disorder

Planning ability (PA) is a key aspect of cognitive functioning and requires subjects to identify and organise the necessary steps to achieve a goal. Despite the central role of executive dysfunction in patients with obsessive-compulsive disorder (OCD), deficits in PA have been investigated leading to contrasting results. Given these inconsistencies, the main aim of our work is to give a deeper and clearer understanding of PA in OCD patients. Moreover, we are interested in investigating the relationship between PAs and impulsivity traits and other clinical variables. Sixty-eight OCD patients and 68 healthy controls (HCs) matched for sex and age were assessed through the Stocking of Cambridge (SoC), a computerised version of the Tower of London. We examined planning sub-components for each difficulty levels (from 2 to 5 minimum moves). Our results showed that OCD patients needed longer initial thinking time than HCs during the execution of low demanding tasks (i.e. 2 and 3 moves), while the accuracy level between the two groups did not significantly differ. OCD patients required longer initial thinking time also during high demanding tasks (i.e., 4 and 5 moves), but in this case their accuracy was significantly worse than HCs' one. We did not find any association between impulsivity and PAs. Our results supported the hypothesis that OCD patients were not able to retain in memory the planned sequence and they had to reschedule their movements during the execution. Thus, future studies should deepen the interrelation between working memory and PA to better understand the influence between these two cognitive functions and their interaction with clinical variables in OCD patients.

Prospective memory in obsessive compulsive disorder

Studies on the nature and extent of prospective memory impairment in patients with obsessive-compulsive disorder are relatively scarce. The present study examined prospective memory in patients with obsessive-compulsive disorder in comparison to patients with schizophrenia and healthy controls. Prospective memory was assessed using Memory for Intentions Screening Test (MIST). Further, the participants were administered Delis-Kaplan Executive Function System Tower Test, Wisconsin Card Sorting Test, and Stroop Test for assessing their planning ability, mental flexibility and cognitive inhibition, respectively. Monitoring was assessed by frequency of clock checking. Results indicated that as compared to healthy controls, the patients with obsessive-compulsive disorder performed poorly on both time- and event-based prospective memory tasks, whereas, patients with schizophrenia performed poorly on time-based prospective memory task only. Further, both the patient groups had comparable performance across time- and event-based tasks. Results of error analysis indicated that patients with obsessive-compulsive disorder mainly committed no response and task substitution errors, whereas patients with schizophrenia committed no response errors. Except monitoring, none of the neurocognitive variables correlated with time or event-based prospective memory in any group. The findings are discussed in the light of their implications for retraining of prospective memory deficits in patients with obsessive-compulsive disorder and schizophrenia.

Executive Functions of Obsessive Compulsive Disorder and Panic Disorder Patients in Comparison to Healty Controls

Introduction

Patients with obsessive compulsive disorder (OCD) have impaired cognitive functions, including attention, verbal and visual memory, and visual-spatial abilities as well as executive function But some studies did not show any disturbance in executive function of patients with OCD. To date, only few studies have been conducted on neuropsychological functioning of patients with panic disorder (PD). There are limited studies to reach a definite conclusion on executive functions of patients with OCD and those with PD. In this study, we aimed to measure executive functions of patients with OCD and those with PD compared with those of healthy controls. Although there are many studies on cognitive functions of patients with OCD, there appears to be no consistency in results and no findings have been obtained to enable us to reach definite conclusions. Although there are very few studies on neuropsychological functions of patients with PD, impairments on a set of cognitive functions have been demonstrated. To date, no finding with respect to impairment in executive functions of patients with PD has been published. PD and OCD are disorders manifesting similar characteristics, with the presence of anxiety and avoidance behavior. Besides this, patients with OCD also have symptoms such as obsessions and compulsions that are characteristics of this disorder. We aim to compare executive functions in the three groups (patients with OCD, those with PD, and healthy controls) in this study.

Method

Seventeen patients with OCD and 15 patients with PD who were diagnosed according to Diagnostic and Statistical Manual of Mental Disorder -IV-TR (DSM-IV-TR) and 26 healthy control subjects were included in this study. Patients who used medication as well as those with medical illnesses and Axis-I comorbidities were excluded. The healthy control group subjects were matched with the patients in terms of age, gender, and education. Structured Clinical Interview for DSM-IV Axis-I Disorders-Clinical Version (SCID-I), Hamilton Depression Rating Scale (HDRS), and Yale-Brown obsessive compulsive scale tests (Y-BOCS) were administered to the patients. Trail Making Tests (TMT), verbal fluency tests (Controlled Oral Word Association Test and Categorical Naming), Stroop Test, and Wisconsin Card Sorting Test (WCST) were administered to the study groups.

Results

According to our results, there was no statistically significant difference between the three study groups with respect to executive functions. There was also no significant correlation between executive tests' results and Y-BOCS'in the OCD group.

Conclusion

The results of the PD group are in line with that reported in literature. The results of the OCD group can be explained by a lack of medication usage and any comorbidity including depression. A small sample size is the major limitation of our study.

Meta-Analysis of Intelligence Quotient (IQ) in Obsessive-Compulsive Disorder

Obsessive compulsive disorder (OCD) is associated with a moderate degree of underperformance on cognitive tests, including deficient processing speed. However, despite little research focusing on Intelligence Quotient (IQ) in OCD, it has long been speculated that the disorder is associated with elevated intellectual capacity. The present meta-analytic study was, therefore, conducted to quantitatively summarize the literature on IQ in OCD systematically. We identified 98 studies containing IQ data among individuals with OCD and non-psychiatric comparison groups, and computed 108 effect sizes for Verbal IQ (VIQ, n = 55), Performance IQ (PIQ, n = 13), and Full Scale IQ (FSIQ, n = 40). Across studies, small effect sizes were found for FSIQ and VIQ, and a moderate effect size for PIQ, exemplifying reduced IQ in OCD. However, mean IQ scores across OCD samples were in the normative range. Moderator analyses revealed no significant moderating effect across clinical and demographic indices. We conclude that, although lower than controls, OCD is associated with normative FSIQ and VIQ, and relatively lowered PIQ. These results are discussed in light of neuropsychological research in OCD, and particularly the putative impact of reduced processing speed in this population. Recommendations for utilization of IQ tests in OCD, and directions for future studies are offered.

Neuropsychological Functioning in Obsessive-Compulsive Washers: Drug-Naive Without Depressive Symptoms

INTRODUCTION

Obsessive-Compulsive Disorder (OCD) is a complex and heterogeneous neuropsychiatric syndrome. Contamination obsessions and washing/cleaning compulsions are the most frequent clinical OCD subtypes. The current study aimed at examining the neuropsychological impairments in drug-naive obsessive-compulsive (OC) washers without depressive symptoms and their association with the severity of symptoms.

METHODS

In the current causal-comparative study, 35 patients with diagnostic and statistical mental disorders class (DSM)-IV diagnosed with washing-subtype OCD and 35 healthy subjects were selected by the convenience sampling method and evaluated by computerized neuropsychology battery and clinical tests as Stroop Color-Word Test (SCWT), Wisconsin Card Sorting Test (WCST), Go/No-Go Test, Digits Forward (DF), Digits Backward (DB), Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), and General Health Questionnaire (GHQ)-28. The patients were matched to the comparison group with regard to age, gender, intelligence quotient (IQ), education, and handedness. All the tests were standardized in Iran. SPSS version 20.00 was used for descriptive and analytical data analysis.

RESULTS

There was no statistically significant different between the OCD washing and the control groups regarding socio-demographic variables or IQ. There were significant differences between the OC washer and the healthy control groups on the neuropsychological functioning. The obtained results suggested that OC washers performed significantly worse on neuropsychological measures than the controls. There was no significant association between the severity of OC symptoms and the neuropsychological functions in the OCD washing group.

CONCLUSION

It was concluded that executive function impairment, which is a core feature in OC washers was trait-like in nature.

Relationships between neuropsychological variables and factor-analysed symptom dimensions in obsessive compulsive disorder

Despite mounting evidence for the distinctiveness of symptom dimensions in obsessive-compulsive disorder, neuropsychological studies have been few, focused on small samples, and relying on classification of participants based on mutually exclusive symptom categories, resulting in lack of concordance across neuropsychological and imaging studies. Neuropsychological assessment was undertaken with 150 individuals with DSM IV OCD, and neuropsychological variables were analysed in relation to symptom dimension scores derived from factor analysis. Five dimensions were derived from principal components analysis with varimax rotation - contamination/washing, doubts/checking, symmetry/ordering, forbidden thoughts, and hoarding. After controlling for severity of depression and OCD, antipsychotic and benzodiazepine use, and all other symptom dimensions, washing was associated with poorer attention/working memory, visuo-spatial construction and better planning time; checking was related to poorer alternation learning; symmetry linked with poorer verbal fluency; forbidden thoughts with better visuospatial scanning and working memory; hoarding with poorer immediate verbal recall and better visuospatial working memory. The neuropsychological associations are explained in the context of existing neuroimaging evidence, and the clinical picture of each symptom dimension. The use of factor-analysed symptom dimensions and a large sample of individuals with OCD are strengths of the study.

Cognitive Dysfunction in Obsessive-Compulsive Disorder

Obsessive-compulsive disorder (OCD) is a mental disorder featuring obsessions (intrusive thoughts) and compulsions (repetitive behaviors performed in the context of rigid rituals). There is strong evidence for a neurobiological basis of this disorder, involving limbic cortical regions and related basal ganglion areas. However, more research is needed to lift the veil on the precise nature of that involvement and the way it drives the clinical expression of OCD. Altered cognitive functions may underlie the symptoms and thus draw a link between the clinical expression of the disorder and its neurobiological etiology. Our extensive review demonstrates that OCD patients do present a broad range of neuropsychological dysfunctions across all cognitive domains (memory, attention, flexibility, inhibition, verbal fluency, planning, decision-making), but some methodological issues temper this observation. Thus, future research should have a more integrative approach to cognitive functioning, gathering contributions of both experimental psychology and more fundamental neurosciences.

Effects of gender and executive function on visuospatial working memory in adult obsessive-compulsive disorder

Visuospatial working memory (VSWM) is the ability of the brain to transiently store and manipulate visual information. VSWM deficiencies have been reported in obsessive-compulsive disorder (OCD), but not consistently, perhaps due to variability in task design and clinical patient factors. To explore this variability, this study assessed effects of the design factors task difficulty and executive organizational strategy and of the clinical factors gender, OCD symptom dimension, and duration of illness on VSWM in OCD. The CANTAB spatial working memory, spatial recognition memory, delayed matching to sample, and stop signal tasks were administered to 42 adult OCD patients and 42 age- and sex-matched healthy controls. Aims were to detect a possible VSWM deficit in the OCD sample, to evaluate influences of the above task and patient factors, to determine the specificity of the deficit to the visuospatial subdomain, and to examine effects of sustained attention as potential neurocognitive confound. We confirmed previous findings of a VSWM deficit in OCD that was more severe for greater memory load (task difficulty) and that was affected by task strategy (executive function). We failed to demonstrate significant deficits in neighboring or confounding neurocognitive subdomains (visual object recognition or visual object short-term memory, sustained attention). Notably, the VSWM deficit was only significant for female patients, adding to evidence for sexual dimorphism in OCD. Again as in prior work, more severe OCD symptoms in the symmetry dimension (but no other dimension) significantly negatively impacted VSWM. Duration of illness had no significant effect on VSWM. VSWM deficits in OCD appear more severe with higher task load and may be mediated through poor task strategy. Such deficits may present mainly in female patients and in (male and female) patients with symmetry symptoms.

The neuropsychology of obsessive-compulsive personality disorder: a new analysis

BACKGROUND

Obsessive compulsive personality disorder (OCPD) is characterized by perfectionism, need for control, and cognitive rigidity. Currently, little neuropsychological data exist on this condition, though emerging evidence does suggest that disorders marked by compulsivity, including obsessive-compulsive disorder (OCD), are associated with impairment in cognitive flexibility and executive planning on neurocognitive tasks.

AIM

The current study investigated the neurocognitive profile in a nonclinical community-based sample of people fulfilling diagnostic criteria for OCPD in the absence of major psychiatric comorbidity.

METHOD

Twenty-one nonclinical subjects who fulfilled Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria for OCPD were compared with 15 healthy controls on selected clinical and neurocognitive tasks. OCPD was measured using the Compulsive Personality Assessment Scale (CPAS). Participants completed tests from the Cambridge Automated Neuropsychological Test Battery including tests of set shifting (Intra-Extra Dimensional [IED] Set Shifting) executive planning (Stockings of Cambridge [SOC]), and decision making (Cambridge Gamble Task [CGT]).

RESULTS

The OCPD group made significantly more IED-ED shift errors and total shift errors, and also showed longer mean initial thinking time on the SOC at moderate levels of difficulty. No differences emerged on the CGT.

CONCLUSIONS

Nonclinical cases of OCPD showed significant cognitive inflexibility coupled with executive planning deficits, whereas decision-making remained intact. This profile of impairment overlaps with that of OCD and implies that common neuropsychological changes affect individuals with these disorders.

An interrogation of cognitive findings in pediatric obsessive-compulsive and related disorders

Current findings in the field of psychology have led to increased interest and a new conceptualization of disorders characterized by repetitive behaviors, namely the obsessive compulsive and related disorders (OCRDs). Scant research, however, has sought to collect and categorize the extant research on pediatric OCRDs. Particularly, no adequate review of the pediatric cognitive literature existed until now, despite the clear implication of abnormalities in neuroanatomical structures and cognitive functioning in adult samples. While evidence for cognitive dysfunction in pediatric samples is presented, this paper also suggests that differences in cognitive dysfunction may indeed exist between adults and youth with OCRDs. Specifically, those irregularities present in said youth at varying developmental stages may impact the origination and maintenance of OCRDs across time. Finally, this paper seeks to formulate potential future goals for the research field, particularly through transdiagnostic approaches to processes linked with symptom presentations. This is of particular importance as an improved understanding of the interaction of cognitive function and growth is key to further comprehension of the OCRDs.

Electrophysiology of facilitation priming in obsessive-compulsive and panic disorders

OBJECTIVE

Repeated experience with stimuli often primes faster, more efficient neuronal and behavioural responses. Exaggerated repetition priming effects have previously been reported in obsessive-compulsive disorder (OCD), however little is known of their underlying neurobiology or disorder-specificity, hence we investigated these factors.

METHODS

We examined event-related potentials (ERPs) and behaviour while participants with OCD, panic disorder and healthy controls (20 per group) performed a Go/NoGo task which manipulated target repetition sequences.

RESULTS

Both clinical groups showed stronger reaction time (RT) priming than HCs, which in OCD was greater in a checking, than washing, subgroup. Both clinical groups had similar RT deficits and ERP anomalies across several components, which correlated with psychopathology and RT priming. In OCD alone, N1 latency tended to increase to repeated stimuli, correlated with O-C symptoms, whereas it decreased in other groups. OCD-checkers had smaller target P2 amplitude than all other groups.

CONCLUSIONS

Enhanced neural priming is not unique to OCD and may contribute to salient sensory-cognitive experiences in anxiety generally. These effects are related to symptom severity and occur to neutral stimuli and in the context of overall RT impairment, suggesting they may be clinically relevant and pervasive. The results indicate overlapping information-processing and neurobiological factors across disorders, with indications of OCD-specific trends and subgroup differences.

SIGNIFICANCE

This first electrophysiological investigation of OCD priming in OCD to include anxious controls and OCD subgroups allows for differentiation between overlapping and OCD-specific phenomena, to advance neurobiological models of OCD.

Checking Behaviours, Prospective Memory and Executive Functions

Explanations implicating memory in the causes and severity of checking symptoms have focused primarily on retrospective memory, and relatively little attention has been paid to prospective memory. Limited research has examined the relationship between prospective memory and executive functions. We assessed whether impairments in prospective memory and executive function predict checking symptoms in a sample of 106 adults. Checking symptoms were assessed using the Padua Inventory Washington State University Revision (PI-WSUR). All participants completed the prospective memory questionnaire (PMQ) and four computerised executive function tasks from the CANTAB, measuring inhibition, planning, attention set-shifting and working memory. Prospective memory and inhibition predicted checking symptom severity. Importantly, there were no correlations between internally cued prospective memory and inhibition or between prospective memory aiding strategies and inhibition. These variables appear to have an independent role in checking. The current findings highlight prospective memory and inhibition as key contributors to the checking symptom profile and provide the first evidence that these cognitive processes may independently contribute to checking symptoms. These findings have implications for a model in which memory performance is thought to be secondary to impairments in executive functions.

Neuropsychological differences between obsessive-compulsive washers and checkers: a systematic review and meta-analysis

Inconsistent results in neuropsychological research of obsessive-compulsive disorder (OCD) may be the result of the heterogeneous nature of OCD symptoms. The most frequently investigated symptoms are contamination/cleaning and doubt/checking. The aim of this review was to determine whether OCD washers and checkers differ in their neuropsychological performance. We conducted a meta-analysis of 13 studies (including 535 patients) comprising tests in 10 different neuropsychological domains. Washers showed significant better task performance than checkers in 8 of 10 cognitive domains. Large effect sizes were found in planning/problem solving and response inhibition. Effect size in set shifting was medium, whereas effect sizes in attention, processing speed, encoding, verbal memory and nonverbal memory were small. Limitations consisted in a relatively small number of primary studies. In line with current neurobiological findings, the results provide further evidence for the validity of different symptom dimensions in OCD. Clinical and theoretical implications are discussed.

Are 5-HT3 antagonists effective in obsessive-compulsive disorder? A systematic review of literature

OBJECTIVE

The purpose of this literature database search-based review was to critically consider and evaluate the findings of literature focusing on efficacy and safety of 5-HT3 antagonists in the treatment of obsessive-compulsive disorder (OCD), so as to test whether preclinical data match clinical therapeutic trials.

DESIGN

The PubMed database has been searched for papers on 5-HT3 antagonists and OCD in humans and for animal models of OCD and 5-HT3 receptors.

RESULTS

Of the clinically tested 5-HT3 receptor antagonists, ondansetron has been used to treat OCD in five therapeutic studies, whereas granisetron only in one recent trial. Both showed some efficacy in open studies and superiority to placebo in double-blind studies, along with fair safety. No animal OCD model directly implicated 5-HT3 receptors.

CONCLUSIONS

Overall, results indicate some utility, but the available literature is too scanty to allow for valid conclusions to be drawn. The mismatch between animal models of obsessive-compulsive disorder and clinical data with 5-HT3 antagonists needs more clinical data to ensure that it is not an artefact.

Body checking as a behavioral link: a preliminary study assessing inhibition and its association to idiosyncratic body checking in anorexia nervosa

Body checking (BC) is a behavioral feature of anorexia nervosa (AN), which is also present in obsessive-compulsive (OC) disorders. This study assessed whether increased body checking in AN patients correlated with deficits in cognitive inhibition. A battery of neuropsychological tests (the Ravello Profile), OC disorder measures, and the Body Checking Questionnaire (BCQ) were administered to nine adolescent females being treated for AN at an in-patient hospital in Scotland, UK. Neuropsychological measures were assessed using composite variables. Body Checking prevalence was split into high and low category to compare across groups. A negative relationship between cognitive inhibition and idiosyncratic body checking was evident. Clinically, increased body-checking symptoms were related to OC symptoms. These findings provide preliminary evidence that idiosyncratic body checking in AN patients may indicate a similar neuropsychological profile found in those with checking behaviors in OCD patients.

Obsessive-compulsive disorder is associated with broad impairments in executive function: A meta-analysis

Obsessive-compulsive disorder (OCD) is a serious and often chronically disabling condition. The current dominant model of OCD focuses on abnormalities in prefrontal-striatal circuits that support executive function (EF). While there is growing evidence for EF impairments associated with OCD, results have been inconsistent, making the nature and magnitude of these impairments controversial. The current meta-analysis uses random-effects models to synthesize 110 previous studies that compared participants with OCD to healthy control participants on at least one neuropsychological measure of EF. The results indicate that individuals with OCD are impaired on tasks measuring most aspects of EF, consistent with broad impairment in EF. EF deficits were not explained by general motor slowness or depression. Effect sizes were largely stable across variation in demographic and clinical characteristics of samples, although medication use, age, and gender moderated some effects.

The neurobiological link between OCD and ADHD

Obsessive compulsive disorder (OCD) and attention deficit hyperactivity disorder (ADHD) are two of the most common neuropsychiatric diseases in paediatric populations. The high comorbidity of ADHD and OCD with each other, especially of ADHD in paediatric OCD, is well described. OCD and ADHD often follow a chronic course with persistent rates of at least 40–50 %. Family studies showed high heritability in ADHD and OCD, and some genetic findings showed similar variants for both disorders of the same pathogenetic mechanisms, whereas other genetic findings may differentiate between ADHD and OCD. Neuropsychological and neuroimaging studies suggest that partly similar executive functions are affected in both disorders. The deficits in the corresponding brain networks may be responsible for the perseverative, compulsive symptoms in OCD but also for the disinhibited and impulsive symptoms characterizing ADHD. This article reviews the current literature of neuroimaging, neurochemical circuitry, neuropsychological and genetic findings considering similarities as well as differences between OCD and ADHD.

Assessing neurocognitive function in psychiatric disorders: a roadmap for enhancing consensus

It has been challenging to identify core neurocognitive deficits that are consistent across multiple studies in patients with Obsessive Compulsive Disorder (OCD). In turn, this leads to difficulty in translating findings from human studies into animal models to dissect pathophysiology. In this article, we use primary data from a working memory task in OCD patients to illustrate this issue. Working memory deficiencies have been proposed as an explanatory model for the evolution of checking compulsions in a subset of OCD patients. However, findings have been mixed due to variability in task design, examination of spatial vs. verbal working memory, and heterogeneity in patient populations. Two major questions therefore remain: first, do OCD patients have disturbances in working memory? Second, if there are working memory deficits in OCD, do they cause checking compulsions? In order to investigate these questions, we tested 19 unmedicated OCD patients and 23 matched healthy controls using a verbal working memory task that has increased difficulty/task-load compared to classic digit-span tasks. OCD patients did not significantly differ in their performance on this task compared to healthy controls, regardless of the outcome measure used (i.e. reaction time or accuracy). Exploratory analyses suggest that a subset of patients with predominant doubt/checking symptoms may have decreased memory confidence despite normal performance on trials with the highest working memory load. These results suggest that other etiologic factors for checking compulsions should be considered. In addition, they serve as a touchstone for discussion, and therefore help us to generate a roadmap for increasing consensus in the assessment of neurocognitive function in psychiatric disorders.

Cognitive functioning in obsessive-compulsive disorder: a meta-analysis

BACKGROUND

Substantial empirical evidence has indicated impairment in the cognitive functioning of patients with obsessive-compulsive disorder (OCD) despite inconsistencies. Although several confounding factors have been investigated to explain the conflicting results, the findings remain mixed. This study aimed to investigate cognitive dysfunction in patients with OCD using a meta-analytic approach.

METHOD

The PubMed database was searched between 1980 and October 2012, and reference lists of review papers were examined. A total of 221 studies were identified, of which 88 studies met inclusion criteria. Neuropsychological performance and demographic and clinical variables were extracted from each study.

RESULTS

Patients with OCD were significantly impaired in tasks that measured visuospatial memory, executive function, verbal memory and verbal fluency, whereas auditory attention was preserved in these individuals. The largest effect size was found in the ability to recall complex visual stimuli. Overall effect estimates were in the small to medium ranges for executive function, verbal memory and verbal fluency. The effects of potentially confounding factors including educational level, symptom severity, medication status and co-morbid disorders were not significant.

CONCLUSIONS

Patients with OCD appear to have wide-ranging cognitive deficits, although their impairment is not so large in general. The different test forms and methods of testing may have influenced the performance of patients with OCD, indicating the need to select carefully the test forms and methods of testing used in future research. The effects of various confounding variables on cognitive functioning need to be investigated further and to be controlled before a definite conclusion can be made.

5-HT3 receptor influences the washing phenotype and visual organization in obsessive-compulsive disorder supporting 5-HT3 receptor antagonists as novel treatment option

A role of the HTR3A-E genes in obsessive-compulsive disorder (OCD) can be expected based on promising effects of 5-HT3 receptor antagonists as adjunctive treatment of OCD. We therefore genotyped six common coding or promoter variants within the HTR3A-E genes in a case-control-sample consisting of N=236 OCD patients and N=310 control subjects and in N=58 parent-child-trios. Given the heterogeneous OCD phenotype, we also investigated OCD symptom dimensions and cognitive endophenotypes in subsamples. OCD patients scoring high for the washing subtype were significantly more likely to carry the c.256G-allele of the HTR3E variant rs7627615 (p=0.0001) as compared to OCD patients low for this symptom dimension. Visual organization was impaired in OCD patients and unaffected relatives as compared to healthy control subjects and carriers of the HTR3E c.256G/c.256G-genotype performed significantly worse (p=0.007). The case-control analyses revealed a nominal significant association of the HTR3D variant rs1000592 (p.H52R) with OCD (p=0.029) which was also evident after combination of the case-control and the trio-results (p=0.024). In male subjects, the variant rs6766410 (p.N163K) located in the HTR3C was significantly associated with OCD (p=0.007). The association findings of the HTR3C and the HTR3E remained significant after correction for the number of variants investigated. These findings indicate a role of common variants of the HTR3A-E genes in OCD and OCD-related phenotypes and further support the use of 5-HT3 receptor antagonists as novel treatment options. The HTR3E gene is a novel candidate gene impacting on the individual expression of OC symptoms and OCD-related cognitive dysfunction.

Impact of obsessive-compulsive symptoms in Tourette's syndrome on neuropsychological performance

AIM

Although inconsistencies in neuropsychological impairments in Tourette's syndrome (TS) have been discussed with respect to comorbid disorders, such as obsessive-compulsive disorder, few studies have focused on the specific dimensions of obsessive-compulsive symptoms (OCS) related to TS, such as aggression and symmetry. The aim of this study was to explore the impact of specific TS-related OCS on neuropsychological performance.

METHODS

A series of neuropsychological tasks examining attention and executive functioning were performed in groups of 33 TS participants and 18 healthy controls. The neuropsychological performance of TS with Aggression OCS (n = 11) were compared to TS without Aggression OCS (n = 22) and controls by using MANCOVA controlling for age. In the same way as Aggression, we compared the performance of three groups by Symmetry: TS with Symmetry OCS (n = 14), TS without Symmetry OCS (n = 19) and controls.

RESULTS

TS participants with Aggression OCS tended to make more perseverative errors than those without. Global OCS severity and tic severity did not correlate with any neuropsychological performances. No significant differences were detected between TS participants with and without Symmetry OCS.

CONCLUSION

Neuropsychological deficits in TS might be affected not by global OCS severity but by specific TS-related OCS.

Neuropsychological performance in OCD: a study in medication-naïve patients

BACKGROUND

Obsessive-compulsive disorder (OCD) is associated with impairments in multiple neuropsychological domains but the findings are rather inconsistent across studies. One potential reason for poor replication is the confounding influence of medications. There is limited research on neuropsychological performance in medication-naïve, never treated OCD patients.

METHODS

In this study, we assessed 31 medication-naïve, never-treated, DSM-IV OCD patients free of comorbid major depression and 31 healthy controls individually matched for age, gender and years of education, with tests of attention, executive function, memory reasoning and visuo-spatial function.

RESULTS

Medication-naïve OCD patients did not significantly differ from healthy controls on most neuropsychological tests. Patients performed somewhat poorly only on the highest goal hierarchy of the Tower of London (TOL) test (p=0.001, effect size=0.68).

CONCLUSIONS

It is intriguing to find that symptomatic, drug-naïve OCD patients did not significantly differ from healthy controls on most neuropsychological tests. Our finding of medium effect size on TOL highest goal hierarchy test suggests that brain regions outside the affective orbitofrontal loop may also be perhaps involved in OCD. This finding however needs replication because of modest effect size. Future studies should focus on studying medication-naïve, co-morbidity-free patients and relatives using symptom dimensions for consistent and robust findings.

Video telemetry and behavioral analysis discriminate between compulsive cleaning and compulsive checking in obsessive-compulsive disorder

Obsessive-compulsive disorder (OCD) patients exhibit compulsive acts that share key characteristics that discriminate them from normal behaviors. In OCD, factor analysis of symptomatology has identified separate clusters (contamination/cleaning; harming/checking; symmetry/ordering; hoarding). Here we used video analysis of the motor characteristics of OCD compulsions derived from two separate clusters, checking and cleaning, in order to determine whether behavioral differences exist in the way these two compulsions are performed. We compared 22 behavioral components (acts) of 12 OC-cleaning rituals and 25 OC-checking rituals. A normal activity with the identical theme was matched for each OC ritual as a control. For each ritual and control, we measured 22 parameters (such as the duration and frequency of act performance), and the levels of functionality, by evaluating the degree to which the act appears to contribute toward achieving its goal. We found that both OC-cleaning and OC-checking rituals differed from their respective control activity, and that they also differ between themselves in seven out of the 22 parameters. OC-cleaning involved increased repetition of functional activity whereas OC-checking involved a relatively increased non-functional activity. These results suggest that OCD cleaning and checking rituals are sufficiently different to justify their division into different subtypes and presumably are sub-served by different mechanisms. A better understanding of the relationship between those behavioral parameters derived from video-telemetry, and the parameters assessed by means of clinical and neurobiological tools, would improve our understanding of the nosological significance of compulsive symptoms and contribute to advancing endophenotypic exploration of the heterogeneity of OCD.

Obsessive-compulsive disorder: a review of the diagnostic criteria and possible subtypes and dimensional specifiers for DSM-V

BACKGROUND

Since the publication of the DSM-IV in 1994, research on obsessive-compulsive disorder (OCD) has continued to expand. It is timely to reconsider the nosology of this disorder, assessing whether changes to diagnostic criteria as well as subtypes and specifiers may improve diagnostic validity and clinical utility.

METHODS

The existing criteria were evaluated. Key issues were identified. Electronic databases of PubMed, ScienceDirect, and PsycINFO were searched for relevant studies.

RESULTS

This review presents a number of options and preliminary recommendations to be considered for DSM-V. These include: (1) clarifying and simplifying the definition of obsessions and compulsions (criterion A); (2) possibly deleting the requirement that people recognize that their obsessions or compulsions are excessive or unreasonable (criterion B); (3) rethinking the clinical significance criterion (criterion C) and, in the interim, possibly adjusting what is considered "time-consuming" for OCD; (4) listing additional disorders to help with the differential diagnosis (criterion D); (5) rethinking the medical exclusion criterion (criterion E) and clarifying what is meant by a "general medical condition"; (6) revising the specifiers (i.e., clarifying that OCD can involve a range of insight, in addition to "poor insight," and adding "tic-related OCD"); and (7) highlighting in the DSM-V text important clinical features of OCD that are not currently mentioned in the criteria (e.g., the major symptom dimensions).

CONCLUSIONS

A number of changes to the existing diagnostic criteria for OCD are proposed. These proposed criteria may change as the DSM-V process progresses.

Should an obsessive-compulsive spectrum grouping of disorders be included in DSM-V?

The obsessive-compulsive (OC) spectrum has been discussed in the literature for two decades. Proponents of this concept propose that certain disorders characterized by repetitive thoughts and/or behaviors are related to obsessive-compulsive disorder (OCD), and suggest that such disorders be grouped together in the same category (i.e. grouping, or "chapter") in DSM. This article addresses this topic and presents options and preliminary recommendations to be considered for DSM-V. The article builds upon and extends prior reviews of this topic that were prepared for and discussed at a DSM-V Research Planning Conference on Obsessive-Compulsive Spectrum Disorders held in 2006. Our preliminary recommendation is that an OC-spectrum grouping of disorders be included in DSM-V. Furthermore, we preliminarily recommend that consideration be given to including this group of disorders within a larger supraordinate category of "Anxiety and Obsessive-Compulsive Spectrum Disorders." These preliminary recommendations must be evaluated in light of recommendations for, and constraints upon, the overall structure of DSM-V.