Deficits In Obsessive-compulsive Disorder Research Articles

Abstract task sequence initiation deficit dissociates anxiety disorders from obsessive-compulsive disorder and healthy controls.

In everyday life, humans perform sequences of tasks. These tasks may be disrupted in people with obsessive-compulsive disorder (OCD). Symptoms, such as compulsions, can be considered sequential and often cause repetitions of tasks that disrupt daily living (e.g., checking the stove while cooking). Motor sequences have been used to study behavioral deficits in OCD. However, not all sequences are motor sequences. Some are more "abstract" in that they are composed of a series of tasks (e.g., chopping and stirring) rather than being dependent on individual actions or stimuli. These abstract task sequences require cognitive control mechanisms for their execution. Although theory has proposed deficits in these sequences in OCD as well, they have not been directly investigated. We tested the hypotheses that OCD participants exhibit deficits in the control mechanisms specific to abstract task sequences and more general flexible behavior (measured with task switching within the sequences), relative to health controls (HCs) and clinical controls (participants with anxiety disorders [ANX]). A total of 112 participants completed abstract task sequences consisting of simple categorization tasks. Surprisingly, participants with OCD did not perform worse than HCs or ANX. However, ANX participants showed impairments specific to sequential control that did not extend to more general flexible control. Thus, we showed a novel behavioral dissociation between OCD and ANX specific to abstract task sequential control. These results also implicate deficits in specific frontal sequential control neural circuitry in ANX and not in OCD, where implicit sequential deficits may more closely align with striatal circuits.

Decision-making deficits in obsessive-compulsive disorder are associated with abnormality of recency and response consistency parameter in prospect valence learning model.

Patients with obsessive-compulsive disorder (OCD) have deficits in decision-making in the Iowa Gambling Task (IGT). However, no study has investigated the parameters of the prospect valence learning (PVL) model in the IGT for OCD. This study aimed to investigate deficits in decision-making in OCD using the PVL model and identify whether the parameters of the PVL model were associated with obsessive-compulsive severity. Forty-seven medication-free patients with OCD were compared with 47 healthy controls (HCs). Decision-making was measured using the total net and block net scores of the IGT. A PVL model with a decay-reinforcement learning rule (PVL-DecayRI) was used to investigate the parameters of the model. Correlation analysis was conducted between each parameter of the PVL-DecayRL and obsessive-compulsive symptoms. The total net score of patients with OCD was significantly lower than that of the HCs. The block net scores of the OCD group did not differ across the five blocks, whereas in the HCs, the fifth block net score was significantly higher than the block net scores of the first and second blocks. The values of the recency and response consistency parameters of the PVL-DecayRI in patients with OCD were significantly lower than those in HCs. The recency parameter positively correlated with the Y-BOCS obsessive score. Meanwhile, there was no correlation between consistency parameter values and symptom severity in OCD. Our detailed analysis of the decision-making deficit in OCD suggests that the most recent outcome has a small influence on the expectancy of prospect valence, as indicated by the lower recency parameter, and is characterized by more impulsive choices, as indicated by the lower consistency parameter.

Investigating Retrospective and Prospective Metamemory Judgments During Episodic Memory in Patients With Obsessive-Compulsive Disorders

It is clear evidence that individuals diagnosed with obsessive-compulsive disorder (OCD) lack confidence in their memory and have low metamemory performance (judgment and accuracy). However, it is still unclear whether low metamemory performance is specific to first, domain general or domain specific, and second, to stimulus domain. To address these issues, we compared individuals diagnosed with OCD and healthy controls (HCs) on recognition, retrospective (judgments of learning [JOL]) and prospective (feeling of knowing [FOK]) metamemory judgments and under three different episodic memory tasks, which consisted of symptom-free, familiar and unfamiliar stimuli (word, scene, and face photo). OCD patients showed lower recognition performance, JOL and FOK judgments, and accuracy in all tasks than HCs. Also, OCD patients were slower than HCs during all cognitive performances. In both groups, metamemory performances were lower in familiar items than unfamiliar items. However, recognition performances were not affected by stimulus type. Our results support the idea of general episodic memory and a metamemory deficit in OCD. Moreover, metamemory deficits in OCD are domain general.

Perseveration and Shifting in Obsessive-Compulsive Disorder as a Function of Uncertainty, Punishment, and Serotonergic Medication

BackgroundThe nature of cognitive flexibility deficits in obsessive-compulsive disorder (OCD), which historically have been tested with probabilistic reversal learning tasks, remains elusive. Here, a novel deterministic reversal task and inclusion of unmedicated patients in the study sample illuminated the role of fixed versus uncertain rules/contingencies and of serotonergic medication. Additionally, our understanding of probabilistic reversal was enhanced through theoretical computational modeling of cognitive flexibility in OCD. MethodsWe recruited 49 patients with OCD, 21 of whom were unmedicated, and 43 healthy control participants matched for age, IQ, and gender. Participants were tested on 2 tasks: a novel visuomotor deterministic reversal learning task with 3 reversals (feedback rewarding/punishing/neutral) measuring accuracy/perseveration and a 2-choice visual probabilistic reversal learning task with uncertain feedback and a single reversal measuring win-stay and lose-shift. Bayesian computational modeling provided measures of learning rate, reinforcement sensitivity, and stimulus stickiness. ResultsUnmedicated patients with OCD were impaired on the deterministic reversal task under punishment only at the first and third reversals compared with both control participants and medicated patients with OCD, who had no deficit. Perseverative errors were correlated with OCD severity. On the probabilistic reversal task, unmedicated patients were only impaired at reversal, whereas medicated patients were impaired at both the learning and reversal stages. Computational modeling showed that the overall change was reduced feedback sensitivity in both OCD groups. ConclusionsBoth perseveration and increased shifting can be observed in OCD, depending on test conditions including the predictability of reinforcement. Perseveration was related to clinical severity and remediated by serotonergic medication.

Obsessive-compulsive disorder: Etiology, neuropathology, and cognitive dysfunction.

This review provides an overview of obsessive-compulsive disorder (OCD) symptoms, including the four partially distinct subtypes of the disorder, current diagnostic criteria, and common comorbidities. Critically, it focuses on the etiology of OCD, including its underlying neuropathology, and examines cognitive dysfunction in OCD. This review study was conducted by library method. We show how dysfunction in cortico-striato-thalamo-cortical (CSTC) circuits may underpin symptoms; and shed light on the putative neurochemistry within these loops such as the role of serotonin, dopamine, and glutamate systems. We also show how OCD is characterized by cognitive dysfunction including problems in cognitive flexibility, visuospatial memory, response inhibition, and goal-directed behavior, linked to aberrant activity within CSTC circuits. In brief, research questions we shed light on include (1) what are the symptoms in OCD; (2) what is the etiology of the disorder and do existing models explain OCD; and (3) what are key cognitive deficits in OCD and do these improve with treatment?

Top-down and bottom-up contributions to memory performance in OCD: A multilevel meta-analysis with clinical implications.

Despite extensive coverage of a relationship between memory performance and executive function in the obsessive-compulsive disorder (OCD) literature, the relative contributions of specific aspects of executive control have remained elusive. We, therefore, extend our previous multilevel meta-analysis (Persson et al., 2021), where demand on executive function was the most significant determinant of memory deficits in OCD, and provide a finer-grained analysis of executive control via a segregation into top-down (attentional control, maintenance and updating, planning) and bottom-up (perceptual integration, perceptual salience) contributions. Our multilevel meta-analytic approach allowed us to accommodate the interdependency of 255 effect sizes from 131 studies, totaling 4,101 OCD patients. Results revealed that maintenance and updating (top-down) and perceptual integration (bottom-up) predicted memory performance generally, and specifically in those with clinical OCD. Exploratory analyses suggested that this effect may be somewhat different among subclinical OCD groups; however, these findings should be considered with conceptual and analytical caveats in mind. We explain these results via deficient sensory (perceptual integration) and working memory (maintenance and updating) gating mechanisms and propose a model to accommodate their expression in OC symptoms. In conclusion, our meta-analysis has expanded understanding of cognitive performance in OCD and identifies the possibility of untapped cognitive targets for intervention. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Obsessive-compulsive disorder is characterized by decreased Pavlovian influence on instrumental behavior.

Obsessive-compulsive disorder (OCD) is characterized by uncontrollable repetitive actions thought to rely on abnormalities within fundamental instrumental learning systems. We investigated cognitive and computational mechanisms underlying Pavlovian biases on instrumental behavior in both clinical OCD patients and healthy controls using a Pavlovian-Instrumental Transfer (PIT) task. PIT is typically evidenced by increased responding in the presence of a positive (previously rewarded) Pavlovian cue, and reduced responding in the presence of a negative cue. Thirty OCD patients and thirty-one healthy controls completed the Pavlovian Instrumental Transfer test, which included instrumental training, Pavlovian training for positive, negative and neutral cues, and a PIT phase in which participants performed the instrumental task in the presence of the Pavlovian cues. Modified Rescorla-Wagner models were fitted to trial-by-trial data of participants to estimate underlying computational mechanism and quantify individual differences during training and transfer stages. Bayesian hierarchical methods were used to estimate free parameters and compare the models. Behavioral and computational results indicated a weaker Pavlovian influence on instrumental behavior in OCD patients than in HC, especially for negative Pavlovian cues. Our results contrast with the increased PIT effects reported for another set of disorders characterized by compulsivity, substance use disorders, in which PIT is enhanced. A possible reason for the reduced PIT in OCD may be impairment in using the contextual information provided by the cues to appropriately adjust behavior, especially when inhibiting responding when a negative cue is present. This study provides deeper insight into our understanding of deficits in OCD from the perspective of Pavlovian influences on instrumental behavior and may have implications for OCD treatment modalities focused on reducing compulsive behaviors.

Sustained attention induces altered effective connectivity of the ascending thalamo-cortical relay in obsessive-compulsive disorder.

Abnormal function of the thalamo-cortical relay is considered a hallmark of obsessive-compulsive disorder (OCD) and aberrant network interactions may underpin many of the clinical and cognitive symptoms that characterize the disorder. Several statistical approaches have been applied to in vivo fMRI data to support the general loss of thalamo-cortical connectivity in OCD. However, (a) few studies have assessed the contextual constraints under which abnormal network interactions arise or (b) have used methods of effective connectivity to understand abnormal network interactions. Effective connectivity is a particularly valuable method as it describes the putative causal influences that brain regions exert over each other, as opposed to the largely statistical consistencies captured in functional connectivity techniques. Here, using dynamic causal modeling (DCM), we evaluated how attention demand induced inter-group differences (HC ≠ OCD) in effective connectivity within a motivated thalamo-cortical network. Of interest was whether these effects were observed on the ascending thalamo-cortical relay, essential for the sensory innervation of the cortex. fMRI time series data from sixty-two participants (OCD, 30; HC, 32) collected using an established sustained attention task were submitted to a space of 162 competing models. Across the space, models distinguished between competing hypotheses of thalamo-cortical interactions. Bayesian model selection (BMS) identified marginally differing likely generative model architectures in OCD and HC groups. Bayesian model averaging (BMA), was used to weight connectivity parameter estimates across all models, with each parameter weighted by each model’s posterior probability, thus providing more stable estimates of effective connectivity. Inferential statistical analyses of estimated parameters revealed two principal results: (1) Significantly reduced intrinsic connectivity of the V1 → SPC pathway in OCD, suggested connective weakness in the early constituents of the dorsal visual pathway; (2) More pertinent with the discovery possibilities afforded by DCM, sustained attention in OCD patients induced significantly reduced contextual modulation of the ascending relay from the thalamus to the prefrontal cortex. These results form an important complement to our understanding of the contextual bases of thalamo-cortical network deficits in OCD, emphasizing vulnerability of the ascending relay.

Executive function in obsessive compulsive disorder at Zagazig University Hospitals: a case-control study

BackgroundExecutive function (EF) domain deficits which most reported include in particular set shifting and inhibition, which are considered main deficits in obsessive-compulsive disorder (OCD). So, this research aimed to assess EF in patients with a primary diagnosis of OCD in comparison to a healthy control group; in order to understand the impaction of this disorder on the patient’s neuropsychological status.ResultsThere was no significant difference between OCD patients and controls regarding demographic characteristics. Average duration of illness in OCD group was 3.97 ± 5.08 years. Forty patients (60.6%) had OCD medication prior to the study. Depression was the most prevalent comorbidity among OCD group (36.4%) then anxiety (12.1%) and social anxiety (3%). Regarding WCST indices, a significant difference (P < 0.05) was found between both groups in total number of correct answers, total number of errors, mean of errors, total number of perseverative errors, mean of perseverative errors, total number of non-perseverative errors, mean of non-perseverative errors, and conceptual level responses without significant difference (P ≥ 0.05) in the remaining indices. In ToL indices, there was highly significant difference (P < 0.001) between both groups regarding total time, but not regarding total moves (P ≥ 0.05). The defect in EF was positively correlated to the severity of symptoms of OCD. There was no significant difference between patients who had been receiving medical treatment and those who had not, also between patients who had comorbidities accompanying OCD and those who had not regarding EF as evident by both WCST measured parameters and TOL parameters.ConclusionsOCD patients appear to have EF deficits in the fields of set-shifting, inhibitory control, working memory, and planning ability.

Striatum-Mediated Deficits in Stimulus-Response Learning and Decision-Making in OCD.

Obsessive compulsive disorder (OCD) is a prevalent psychiatric disorder characterized by obsessions and compulsions. Studies investigating symptomatology and cognitive deficits in OCD frequently implicate the striatum. The aim of this study was to explore striatum-mediated cognitive deficits in patients with OCD as they complete a stimulus-response learning task previously shown to differentially rely on the dorsal (DS) and ventral striatum (VS). We hypothesized that patients with OCD will show both impaired decision-making and learning, coupled with reduced task-relevant activity in DS and VS, respectively, compared to healthy controls. We found that patients with OCD (n = 14) exhibited decision-making deficits and learned associations slower compared to healthy age-matched controls (n = 16). Along with these behavioral deficits, OCD patients had reduced task-relevant activity in DS and VS, compared to controls. This study reveals that responses in DS and VS are altered in OCD, and sheds light on the cognitive deficits and symptoms experienced by patients with OCD.

Role of comorbid depressive symptoms on the cognitive deficits in obsessive compulsive disorder.

Background:Obsessive compulsive disorder (OCD) is a chronic distressing condition that is marked with impairment in daily functioning including social, family, and occupational areas of life. Depression is the most common comorbidity among patients with OCD. The presence of co-occurring depressive symptoms adds to the burden of the OCD. Previous studies with neuropsychological testing reveals a pattern of cognitive deficits among patients with OCD. Few studies have also shown that the cognitive deficits in OCD are mediated by comorbid depressive symptoms.Objective:The objective of this study was to assess whether the comorbid depressive symptoms have any role on the cognitive deficits in OCD.Methodology:Forty patients diagnosed with OCD with an elevated rating in Beck Depression Inventory (BDI) and 20 normal controls were chosen for the study. The forty patients were split according to the severity scores of BDI as per one group consisting of patients with only mild depression and other group consisting of patients with moderate and severe depression. Yale–Brown Obsessive Compulsive Scale has been administered to assess the severity and symptoms of the disorder. Digit Vigilance Test and Triads Test have been administered to assess attention; Comprehensive Trial Making Test (CTMT) and Rey Complex Figure Test have been administered to assess attention, executive function, and memory.Results:OCD patients have significantly performed poor than the normal controls. On further analysis, OCD patients with moderate and severe depressive features have performed poor than the patients with mild depressive features on the tests administered for attention, executive function, and memory. On assessing the role of comorbid depressive features on cognitive deficits, having mild depressive features were not found to be significantly correlated to the cognitive deficits, whereas patients having moderate and severe depressive features were found to be significantly correlated to the cognitive deficits among OCD patients.Conclusion:The findings suggest that the higher level of depressive symptoms is associated with cognitive deficits in OCD patients. It can be suggested that the comorbid moderate-to-severe depressive symptoms play an important role in the cognitive deficits found among the OCD patients.

Structural neuroimaging correlates of social deficits are similar in autism spectrum disorder and attention-deficit/hyperactivity disorder: analysis from the POND Network

Autism spectrum disorder (ASD), attention-deficit/hyperactivity disorder (ADHD), and obsessive-compulsive disorder (OCD) have been associated with difficulties recognizing and responding to social cues. Neuroimaging studies have begun to map the social brain; however, the specific neural substrates contributing to social deficits in neurodevelopmental disorders remain unclear. Three hundred and twelve children underwent structural magnetic resonance imaging of the brain (controls = 32, OCD = 44, ADHD = 77, ASD = 159; mean age = 11). Their social deficits were quantified on the Social Communication Questionnaire (SCQ) and the Reading the Mind in the Eyes Test (RMET). Multivariable regression models were used to examine the structural neuroimaging correlates of social deficits, with both a region of interest and a whole-brain vertex-wise approach. For the region of interest analysis, social brain regions were grouped into three networks: (1) lateral mentalization (e.g., temporal–parietal junction), (2) frontal cognitive (e.g., orbitofrontal cortex), and (3) subcortical affective (e.g., limbic system) regions. Overall, social communication deficits on the SCQ were associated with thinner cortices in the left lateral regions and the right insula, and decreased volume in the ventral striatum, across diagnostic groups (p = 0.006 to <0.0001). Smaller subcortical volumes were associated with more severe social deficits on the SCQ in ASD and ADHD, and less severe deficits in OCD. On the RMET, larger amygdala/hippocampal volumes were associated with fewer deficits across groups. Overall, patterns of associations were similar in ASD and ADHD, supporting a common underlying biology and the blurring of the diagnostic boundaries between these disorders.

Resting-State Default Mode Network Related Functional Connectivity Is Associated With Sustained Attention Deficits in Schizophrenia and Obsessive-Compulsive Disorder.

Background: Previous studies have indicated the resting-state default mode network (DMN) related connectivity serving as predictor of sustained attention performance in healthy people. Interestingly, sustained attention deficits as well as DMN-involved functional connectivity (FC) alterations are common in both patients with schizophrenia (SCZ) and with obsessive-compulsive disorder (OCD). Thus, the present study was designed to investigate whether the DMN related resting-state connectivity alterations in these two psychiatric disorders were neural correlates of their sustained attention impairments.Methods: The study included 17 SCZ patients, 35 OCD patients and 36 healthy controls (HCs). Sustained attention to response task was adopted to assess the sustained attention. Resting-state scan was administrated and seed-based whole-brain FC analyses were performed with seeds located in classical DMN regions including bilateral medial prefrontal cortex (mPFC) and posterior cingulate cortex (PCC).Results: Both SCZ and OCD patients had poorer sustained attention than HCs. Sustained attention deficits in OCD was negatively correlated with their impaired FC of right mPFC-left superior frontal gyrus (SFG) within DMN, and that in SCZ was significantly correlated with their altered FC of left mPFC-bilateral anterior cingulate cortex (ACC) which indicated interaction between DMN and salience network. In addition, the FC between left mPFC and right parietal lobe indicating the interaction between DMN and frontal-parietal network was correlated with sustained attention in both SCZ and OCD.Conclusion: These findings suggest the importance of DMN-involved connectivity, both within and between networks in underlying sustained attention deficits in OCD and SCZ. Results further support the potential of resting-state FC in complementing information for cognitive deficits in psychiatric disorders.

Dysfunction by Disclosure? Stereotype Threat as a Source of Secondary Neurocognitive Malperformance in Obsessive-Compulsive Disorder.

There is mixed evidence regarding whether patients with obsessive-compulsive disorder (OCD) display substantial neurocognitive deficits. Several studies implicate poor motivation, comorbid disorders, or distraction due to obsessive thoughts as potential causes of secondary malperformance. The present study examined the impact of stereotype threat (i.e., confrontation with a negative stereotype may impair performance) on neuropsychological functioning in individuals with OCD. We hypothesized that a stereotype threat cue emphasizing neurocognitive deficits in OCD (as is often conveyed in disclosure and consent documents that inform patients about the purpose of a study) would compromise patients' test performance relative to a control group who did not receive such cue. Fifty participants with either a verified or a likely diagnosis of OCD were recruited online and randomly assigned to either an experimental condition aimed to elicit stereotype threat or a control condition. Both groups underwent (objective) memory and attention (Go/NoGo task) assessments and completed questionnaires capturing psychopathology, cognitive complaints, and self-stigma. As hypothesized, patients in the stereotype threat condition performed worse on the Go/NoGo task. Groups did not differ on any other measures. Stereotype threat negatively impacted neuropsychological performance on an attention task. The threat cue was perhaps too weak or the stereotype threat was already internalized by the patients and "saturated" at baseline so that no effect emerged on the other measures. Implications for clinical trials are discussed. (JINS, 2018, 24, 584-592).

Morphometric and Connectivity White Matter Abnormalities in Obsessive Compulsive Disorder

Two psychological mechanisms seem to be associated with the obsessive-compulsive cycle: (1) an emotional mechanism characterized by intense emotional arousal associated with intrusive thoughts of impending danger; (2) a cognitive mechanism exemplified by difficulties with inhibitory control. More recently, several studies found more extensive cognitive deficits in Obsessive Compulsive Disorder (OCD) beyond problems of inhibitory control and emotional regulation, namely: visual-spatial processing and memory. Thus, there is now extensive research showing that alterations of these psychological mechanisms in OCD (i.e., inhibitory control, emotional regulation, working memory, and visual spatial processing) are associated with morphological gray matter alterations in widespread brain regions. More recently, researchers have started looking at white matter abnormalities in OCD. In this article we review the research looking at white matter morphometric and structural connectivity alterations in OCD. Altogether, while some contradictory findings are still present, there is now evidence for widespread white matter morphometric and connectivity abnormalities affecting major white matter tracts (superior longitudinal fasciculus, inferior fronto-occipital fasciculus, inferior longitudinal fasciculus, cingulum bundle, semioval center, internal capsule, different regions of the corpus callosum, thalamic radiation, uncinate fasciculus and optic radiation) as well as white matter in regions adjacent to gray matter structures (superior frontal gyrus, dorsolateral prefrontal medial frontal cortex; inferior frontal gyrus, caudate, insulate cortex, parietal cortex, supramarginal and lingual gyri, and thalamus). These white matter alterations may help explaining the diversity of OCD psychological impairments in inhibitory control, emotional regulation, memory and visual spatial processing.

Decreased memory confidence in obsessive-compulsive disorder for scenarios high and low on responsibility: is low still too high?

Previous research suggests that patients with obsessive-compulsive disorder (OCD), particularly checkers, display an inflated sense of responsibility. For the present study, we tested whether memory confidence in OCD is reduced under conditions of heightened responsibility and/or reflects poor memory vividness. A computerized task designed to modulate perceived responsibility was administered to 26 OCD patients (12 checkers) and 21 healthy controls. In the experimental condition (high responsibility), participants had to allocate daily medications to ten fictive patients in a hospital emergency ward, whereas in the control condition (low responsibility) participants had to allocate bath essences for ten hotel guests. Participants' response time and accuracy were recorded as well as their memory confidence, memory vividness, and subjective success. Irrespective of the condition, OCD patients performed as accurately as healthy controls, but appraised their performance as worse than that of controls. Memory confidence was decreased in patients, particularly checkers. No group differences emerged on vividness, and none of the effects were moderated by the condition (high versus low responsibility). The relationship between responsibility and OCD behavior is complex. Results suggest metamemory problems in OCD checkers, even when induced responsibility is low. The findings speak against "cold" memory deficits in OCD, as patients did not differ from controls on accuracy, reaction time, or vividness. Future research should focus on idiosyncratic beliefs and scenarios that inflate responsibility and elicit cognitive biases.

Examining procedural working memory processing in obsessive-compulsive disorder

Previous research has suggested that a deficit in working memory might underlie the difficulty of obsessive-compulsive disorder (OCD) patients to control their thoughts and actions. However, a recent meta-analyses found only small effect sizes for working memory deficits in OCD. Recently, a distinction has been made between declarative and procedural working memory. Working memory in OCD was tested mostly using declarative measurements. However, OCD symptoms typically concerns actions, making procedural working-memory more relevant. Here, we tested the operation of procedural working memory in OCD. Participants with OCD and healthy controls performed a battery of choice reaction tasks under high and low procedural working memory demands. Reaction-times (RT) were estimated using ex-Gaussian distribution fitting, revealing no group differences in the size of the RT distribution tail (i.e., τ parameter), known to be sensitive to procedural working memory manipulations. Group differences, unrelated to working memory manipulations, were found in the leading-edge of the RT distribution and analyzed using a two-stage evidence accumulation model. Modeling results suggested that perceptual difficulties might underlie the current group differences. In conclusion, our results suggest that procedural working-memory processing is most likely intact in OCD, and raise a novel, yet untested assumption regarding perceptual deficits in OCD.

Increased fronto-striatal reward prediction errors moderate decision making in obsessive-compulsive disorder.

Obsessive-compulsive disorder (OCD) has been linked to functional abnormalities in fronto-striatal networks as well as impairments in decision making and learning. Little is known about the neurocognitive mechanisms causing these decision-making and learning deficits in OCD, and how they relate to dysfunction in fronto-striatal networks. We investigated neural mechanisms of decision making in OCD patients, including early and late onset of disorder, in terms of reward prediction errors (RPEs) using functional magnetic resonance imaging. RPEs index a mismatch between expected and received outcomes, encoded by the dopaminergic system, and are known to drive learning and decision making in humans and animals. We used reinforcement learning models and RPE signals to infer the learning mechanisms and to compare behavioural parameters and neural RPE responses of the OCD patients with those of healthy matched controls. Patients with OCD showed significantly increased RPE responses in the anterior cingulate cortex (ACC) and the putamen compared with controls. OCD patients also had a significantly lower perseveration parameter than controls. Enhanced RPE signals in the ACC and putamen extend previous findings of fronto-striatal deficits in OCD. These abnormally strong RPEs suggest a hyper-responsive learning network in patients with OCD, which might explain their indecisiveness and intolerance of uncertainty.

Resting-state functional connectivity between right anterior insula and right orbital frontal cortex correlate with insight level in obsessive-compulsive disorder.

Few studies have explored the neurobiological basis of insight level in obsessive-compulsive disorder (OCD), though the salience network (SN) has been implicated in insight deficits in schizophrenia. This study was then designed to investigate whether resting-state (rs) functional connectivity (FC) of SN was associated with insight level in OCD patients. We analyzed rs-functional magnetic resonance imaging (fMRI) data from 21 OCD patients with good insight (OCD-GI), 19 OCD patients with poor insight (OCD-PI), and 24 healthy controls (HCs). Seed-based whole-brain FC and ROI (region of interest)-wise connectivity analyses were performed with seeds/ROIs in the bilateral anterior insula (AI) and dorsal anterior cingulate cortex (dACC). The right AI-right medial orbital frontal cortex (mOFC) connectivity was found to be uniquely decreased in the OCD-PI group, and the value of this aberrant connectivity correlated with insight level in OCD patients. In addition, we found that the OCD-GI group had significantly increased right AI-left dACC connectivity within the SN, relative to HCs (overall trend for groups: OCD-GI > OCD-PI > HC). Our findings suggest that abnormal right AI-right mOFC FC may mediate insight deficits in OCD, perhaps due to impaired encoding and integration of self-evaluative information about OCD-related beliefs and behaviors. Our findings indicate a SN connectivity dissociation between OCD-GI and OCD-PI patients and support the notion of considering OCD-GI and OCD-PI as two distinct disorder subtypes.

Memory functioning in obsessive-compulsive disorder.

A number of studies have reported neuropsychological deficits in obsessive-compulsive disorder (OCD). These have mainly implicated frontal or temporal dysfunction. In this study, we compared the performances of OCD patients and normal subjects using a factorial interpretation of the Wechsler Memory Scale. Our results do not demonstrate significant memory impairment in OCD patients but point to the possibility of frontal lobe dysfunction as a factor in the pathophysiology of OCD.