Basal-corticofrontal circuits in schizophrenia and obsessive-compulsive disorder: a controlled, double dissociation study

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.

Cognitive flexibility in schizophrenia: A confirmatory factor analysis of neuropsychological measures

Cognitive flexibility (CF) is the ability to adapt cognitive strategies according to the changing environment. The deficit in CF has often been linked to various neurological and psychiatric disorders including schizophrenia. However, the operationalization and assessment of CF have not been unified and the current research suggests that the available instruments measure different aspects of CF. The main objective of the present study was to compare three frequently used neuropsychological measures of CF-Wisconsin Card Sorting Test (WCST), Trail Making Test (TMT) and Stroop Color and Word Test (SCWT) in a population of patients (N = 220) with first-episode schizophrenia spectrum disorders in order to evaluate their convergent validity. The hypothesis of an underlying latent construct was tested via a confirmatory factor analysis. We used a one-factor CF model with scores from WCST, SCWT and TMT as observed variables. The established model showed a good fit to the data (χ² = 1.67, p = 0.43, SRMR = 0.02, RMSEA = 0.0, CFI = 1.00). The highest factor loading was found in WCST as CF explained most of the variance in this neuropsychological measure compared to the other instruments. On the other hand, a TMT ratio index and a SCWT interference demonstrated lowest loadings in the model. The findings suggest that not all the frequently used measures share an underlying factor of CF or may capture different aspects of this construct.

The time scales of irreversibility in spontaneous brain activity are altered in obsessive compulsive disorder

We study how obsessive-compulsive disorder (OCD) affects the complexity and time-reversal symmetry-breaking (irreversibility) of the brain resting-state activity as measured by magnetoencephalography (MEG). Comparing MEG recordings from OCD patients and age/sex matched control subjects, we find that irreversibility is more concentrated at faster time scales and more uniformly distributed across different channels of the same hemisphere in OCD patients than in control subjects. Furthermore, the interhemispheric asymmetry between homologous areas of OCD patients and controls is also markedly different. Some of these differences were reduced by 1-year of Kundalini Yoga meditation treatment. Taken together, these results suggest that OCD alters the dynamic attractor of the brain's resting state and hint at a possible novel neurophysiological characterization of this psychiatric disorder and how this therapy can possibly modulate brain function.

Functional connectivity abnormalities of brain networks in obsessive–compulsive disorder: a systematic review

Obsessive-compulsive disorder (OCD) is characterized by cognitive abnormalities encompassing several executive processes. Neuroimaging studies highlight functional abnormalities of executive fronto-parietal network (FPN) and default-mode network (DMN) in OCD patients, as well as of the prefrontal cortex (PFC) more specifically. We aim at assessing the presence of functional connectivity (FC) abnormalities of intrinsic brain networks and PFC in OCD, possibly underlying specific computational impairments and clinical manifestations. A systematic review of resting-state fMRI studies investigating FC was conducted in unmedicated OCD patients by querying three scientific databases (PubMed, Scopus, PsycInfo) up to July 2022 (search terms: “obsessive–compulsive disorder” AND “resting state” AND “fMRI” AND “function* *connect*” AND “task-positive” OR “executive” OR “central executive” OR “executive control” OR “executive-control” OR “cognitive control” OR “attenti*” OR “dorsal attention” OR “ventral attention” OR “frontoparietal” OR “fronto-parietal” OR “default mode” AND “network*” OR “system*”). Collectively, 20 studies were included. A predominantly reduced FC of DMN – often related to increased symptom severity – emerged. Additionally, intra-network FC of FPN was predominantly increased and often positively related to clinical scores. Concerning PFC, a predominant hyper-connectivity of right-sided prefrontal links emerged. Finally, FC of lateral prefrontal areas correlated with specific symptom dimensions. Several sources of heterogeneity in methodology might have affected results in unpredictable ways and were discussed. Such findings might represent endophenotypes of OCD manifestations, possibly reflecting computational impairments and difficulties in engaging in self-referential processes or in disengaging from cognitive control and monitoring processes.

Obsessive-compulsive symptoms in patient with schizophrenia: The influence of disorganized symptoms, duration of schizophrenia, and drug resistance

BACKGROUND

Schizophrenia is a chronic mental disorder with a many-faced clinical presentation. Obsessive-compulsive symptoms are often part of it. The characteristics of the clinical picture and the course of schizophrenia are factors related to both the resistance and the manifestation of obsessive-compulsive symptoms. Our study aims to establish the relationship between the peculiarities of the schizophrenia process and the influence of resistance on the expression of obsessive-compulsive symptoms.

METHODS

A study was conducted on 105 patients with schizophrenia. Of them, 39 are men and 66 are women. The evaluation of the effectiveness of the treatment showed that 45 were resistant to the applied therapy, while the remaining 60 responded. Clinical assessment of patients was performed using the Positive and Negative Syndrome Scale (PANSS) and Brief Psychiatric Rating Scale (BPRS). Assessment of obsessive-compulsive symptoms (OCS) was conducted with the Dimensional obsessive-compulsive symptoms scale (DOCS).

RESULTS

In 34% of all patients, we found clinically expressed obsessive-compulsive symptoms. In 40% of the patients with resistance, we found clinically expressed obsessive-compulsive symptoms, which are within the range of moderately expressed. In 30% of the patients in clinical remission, we found obsessive-compulsive symptoms, but mildly expressed. We found a statistically significant relationship between the severity of OCS and the disorganized symptoms and the duration of the schizophrenia process. No differences were found in the expression of OCS in patients of both sexes.

CONCLUSION

We registered both an increased frequency and an increased expression of obsessive-compulsive symptoms in patients with resistant schizophrenia. These symptoms were positively associated with disorganized symptoms and duration of schizophrenia. No relationship was established with the positive, negative symptoms, as well as with the gender distribution.

The rostral zona incerta: a subcortical integrative hub and potential DBS target for OCD

BACKGROUND

The zona incerta (ZI) is involved in mediating survival behaviors and is connected to a wide range of cortical and subcortical structures, including key basal ganglia nuclei. Based on these connections and their links to behavioral modulation, we propose that the ZI is a connectional hub for mediating between top-down and bottom-up control and a possible target for deep brain stimulation for obsessive-compulsive disorder.

METHODS

We analyzed the trajectory of cortical fibers to the ZI in nonhuman and human primates based on tracer injections in monkeys and high-resolution diffusion magnetic resonance imaging in humans. The organization of cortical and subcortical connections within the ZI were identified in the nonhuman primate studies.

RESULTS

Monkey anatomical data and human diffusion magnetic resonance imaging data showed a similar trajectory of fibers/streamlines to the ZI. Prefrontal cortex/anterior cingulate cortex terminals all converged within the rostral ZI, with dorsal and lateral areas being most prominent. Motor areas terminated caudally. Dense subcortical reciprocal connections included the thalamus, medial hypothalamus, substantia nigra/ventral tegmental area, reticular formation, and pedunculopontine nucleus and a dense nonreciprocal projection to the lateral habenula. Additional connections included the amygdala, dorsal raphe nucleus, and periaqueductal gray.

CONCLUSIONS

Dense connections with dorsal and lateral prefrontal cortex/anterior cingulate cortex cognitive control areas and the lateral habenula and the substantia nigra/ventral tegmental area, coupled with inputs from the amygdala, hypothalamus, and brainstem, suggest that the rostral ZI is a subcortical hub positioned to modulate between top-down and bottom-up control. A deep brain stimulation electrode placed in the rostral ZI would not only involve connections common to other deep brain stimulation sites but also capture several critically distinctive connections.

Cognitive and behavioural flexibility: neural mechanisms and clinical considerations

Cognitive and behavioural flexibility permit the appropriate adjustment of thoughts and behaviours in response to changing environmental demands. Brain mechanisms enabling flexibility have been examined using non-invasive neuroimaging and behavioural approaches in humans alongside pharmacological and lesion studies in animals. This work has identified large-scale functional brain networks encompassing lateral and orbital frontoparietal, midcingulo-insular and frontostriatal regions that support flexibility across the lifespan. Flexibility can be compromised in early-life neurodevelopmental disorders, clinical conditions that emerge during adolescence and late-life dementias. We critically evaluate evidence for the enhancement of flexibility through cognitive training, physical activity and bilingual experience.

Obsessive-Compulsive Disorder and Decision Making under Ambiguity: A Systematic Review with Meta-Analysis

In the last decade, decision-making has been proposed to have a central role in obsessive-compulsive disorder (OCD) aetiology, since patients show pathological doubt and an apparent inability to make decisions. Here, we aimed to comprehensively review decision making under ambiguity, as measured by the Iowa Gambling Task (IGT), in OCD, using a meta-analytic approach. According to PRISMA Guidelines, we selected 26 studies for a systematic review and, amongst them, 16 studies were included in a meta-analysis, comprising a total of 846 OCD patients and 763 healthy controls (HC). Our results show that OCD patients perform significantly lower than HC at the IGT, pointing towards the direction of a decision making impairment. In particular, this deficit seems to emerge mainly in the last three blocks of the IGT. IGT scores in OCD patients under the age of 18 were still significantly lower than in HC. Finally, no difference emerged between medicated and unmedicated patients, since they both scored significantly lower at the IGT compared to HC. In conclusion, our results are in line with the hypothesis according to which decision making impairment might represent a potential endophenotype lying between the clinical manifestation of OCD and its neurobiological aetiology.

White matter microstructure and connectivity in patients with obsessive-compulsive disorder and their unaffected siblings

OBJECTIVE

We aimed to examine white matter microstructure and connectivity in individuals with obsessive-compulsive disorder (OCD) and their unaffected siblings, relative to healthy controls.

METHODS

Diffusion-weighted magnetic resonance imaging (dMRI) scans were acquired in 30 patients with OCD, 21 unaffected siblings, and 31 controls. We examined white matter microstructure using measures of fractional anisotropy (FA), radial diffusivity (RD), and axial diffusivity (AD). Structural networks were examined using network-based statistic (NBS).

RESULTS

Compared to controls, OCD patients showed significantly reduced FA and increased RD in clusters traversing the left forceps minor, inferior fronto-occipital fasciculus, anterior thalamic radiation, and cingulum. Furthermore, the OCD group displayed significantly weaker connectivity (quantified by the streamline count) compared to controls in the right hemisphere, most notably in edges connecting subcortical structures to temporo-occipital cortical regions. The sibling group showed intermediate streamline counts, FA and RD values between OCD and healthy control groups in connections found to be abnormal in patients with OCD. However, these reductions did not significantly differ compared to controls.

CONCLUSION

Therefore, siblings of OCD patients display intermediate levels in dMRI measures of microstructure and connectivity, suggesting white matter abnormalities might be related to the familial predisposition for OCD.

Double-Dissociation Studies in Psychiatric Research: A Scoping Review

LEARNING OBJECTIVES

After participating in this activity, learners should be better able to:• Evaluate the double-dissociation approach to research in neuropsychology• Assess research aiming to provide evidence of double dissociation between neurobiological abnormalities and clinical presentations in psychiatry BACKGROUND: Psychiatric neuroscience research has grown exponentially, but it has not generated the desired breakthroughs in diagnosis, treatment development, or treatment selection. In many instances a given neurobiological abnormality is found in multiple clinical syndromes, and conversely, a clinical syndrome is associated with multiple neurobiological abnormalities. To the extent that neurobiology research is conducted to explain psychiatric manifestations, however, it should also provide insight into how certain brain abnormalities lead to one and not another specific clinical presentation-that is, "double-dissociation." We hypothesized that most psychiatric research studies are not designed to identify such double dissociations.

METHODS

We selected three leading psychiatric journals (American Journal of Psychiatry, JAMA Psychiatry, and Molecular Psychiatry) that are representative of high-quality psychiatry research and that also provided a sample size that was feasible to screen. We screened all original research manuscripts published over the course of one calendar year (2017) to identify those measuring brain function or biological parameters (which, collectively, we term neurobiological measures) in psychiatric disorders. We asked whether such biological research could provide evidence for a double dissociation of any kind.

RESULTS

We found that only 7 of 403 articles published in three psychiatry journals, constituting approximately 2% of publications, examined the dissociation of neurobiological measures relating to two psychiatric disorders or symptom clusters. Of these 7 studies, 5 used imaging as research tool; 1 used genotype array; and 1 used polymerase chain reaction (PCR). Sample sizes of the 7 studies ranged from 100 to 2876.

CONCLUSION

We report on a striking paucity of research aiming to provide evidence of double dissociation between neurobiological abnormalities and clinical presentations in psychiatry. We conclude that this paucity represents a missed opportunity for the field. Double-dissociation approaches have been used successfully in many studies in neurology and psychiatry in the past, and more widespread and explicit adoption of this design may improve the mechanistic insights obtained in psychiatry research.

Functional Connectivity of the Striatum as a Neural Correlate of Symptom Severity in Patient with Obsessive-Compulsive Disorder

OBJECTIVE

It is well established that the cortico-striato-thalamo-cortical (CSTC) circuit is implicated in the pathophysiology of obsessive- compulsive disorder (OCD). However, reports on corticostriatal functional connectivity (FC) in OCD have been inconsistent due to the structural and functional heterogeneity of the striatum. Therefore, in the present study, we investigated corticostriatal FC using a fine 12-seed striatal parcellation to overcome this heterogeneity and discover the neural correlates of symptoms in OCD patients.

METHODS

We recruited 23 OCD patients and 23 healthy controls (HCs). Whole-brain FC based on striatal seeds was examined using resting-state functional magnetic resonance imaging data and compared across OCD patients and HCs. We conducted correlation analysis between FCs of striatal subregions with significant group differences and symptom severity scores on the Yale-Brown Obsessive Compulsive Scale (Y-BOCS), Hamilton Rating Scale for Depression, and Hamilton Rating Scale for Anxiety (HAM-A).

RESULTS

Compared to HCs, patients demonstrated increased FC of the dorsal caudal putamen and ventral rostral putamen (VRP) with several cortical regions, such as the intracalcarine cortex, inferior frontal gyrus, supramarginal/angular gyrus (SMG/AG), and postcentral gyrus (PCG). Furthermore, FC between the VRP and SMG/AG and between the VRP and PCG was negatively correlated with scores on the Y-BOCS compulsive subscale and the HAM-A, respectively.

CONCLUSION

These findings suggest that striatal subregions have strengthened FC with extensive cortical regions, which may reflect neural correlates of compulsive and anxious symptoms in OCD patients. These results contribute to an improved understanding of OCD pathophysiology by complementing the current evidence regarding striatal FC.

Reward-driven decision-making impairments in schizophrenia

The ability to use feedback to guide optimal decision-making is essential for goal-directed behaviour. While impairments in feedback-driven decision-making have been associated with schizophrenia and depression, this has been examined primarily in the context of binary probabilistic choice paradigms. In real-world decision-making, however, individuals must make choices when there are more than two competing options that vary in the frequency and magnitude of potential rewards and losses. Thus, the current study examined win-stay/lose-shift (WSLS) behaviour on the Iowa Gambling Task (IGT) in order to evaluate the influence of immediate rewards and losses in guiding real-world decision-making in patients with schizophrenia and major depressive disorder. Fifty-one patients with schizophrenia, 43 patients with major depressive disorder, and 51 healthy controls completed the IGT, as well as a series of clinical and cognitive measures. WSLS was assessed by quantifying trial-by-trial behaviour following rewards and losses on the IGT. Multivariate analyses of variance revealed that patients with schizophrenia demonstrated intact lose-shift behaviour, but significantly reduced win-stay rates compared to healthy controls. In contrast, no WSLS impairments emerged in the depressed group. Win-stay impairments in the schizophrenia group were significantly related to deficits in motivation and cognition. Patients with schizophrenia exhibit impaired reward-driven decision-making in the context of multiple choices with concurrent rewards and losses, and this appears to be driven by a reduced propensity for advantageous win-stay behaviour. With the importance of reward learning and decision-making in generating goal-directed behaviour, these findings suggest a potential mechanism contributing to the motivation deficits seen in schizophrenia.

Impairment in planning tasks of children and adolescents with anxiety disorders

Anxiety disorders are associated with poor neuropsychological performance in attention and memory. However, little is known about the impact of these difficulties on other cognitive functions, such as planning. The ability to plan, including attention, working memory and set-shifting components, can be assessed by the Tower of Hanoi task (ToH). This study evaluated seventy-one participants, aged from 7-17 years. Thirty-seven subjects met DSM-IV diagnostic criteria for at least one anxiety disorder and 34 individuals comprised the controls. The neuropsychological tests used were: the ToH, a problem-solving task, involves planning ability and other executive functions (working memory, attentional control and cognitive flexibility); for the assessment of processing speed and problem-solving, the Vocabulary/Matrix Reasoning subtests of the Wechsler Abbreviated Scale of Intelligence was used to measure for estimated-IQ in both groups. The groups were compared with a generalized linear model controlling for age, IQ and ADHD comorbidity. Compared with controls, anxiety disorders subjects made more errors and required more time to complete the ToH. Children and adolescents with anxiety disorders have poorer planning ability compared to subjects without anxiety disorders, and the difficulty in planning is affected by interference from other cognitive functions, such as attention, working memory, cognitive flexibility and problems-solutions.

Neurocognitive assessment in obsessive compulsive disorder patients: Adherence to behavioral decision models

In economics, models of decision-making under risk are widely investigated. Since many empirical studies have shown patterns in choice behavior that classical models fail to predict, several descriptive theories have been developed. Due to an evident phenotypic heterogeneity, obsessive compulsive disorder (OCD) patients have shown a general deficit in decision making when compared to healthy control subjects (HCs). However, the direction for impairment in decision-making in OCD patients is still unclear. Hence, bridging decision-making models widely used in the economic literature with mental health research may improve the understanding of preference relations in severe patients, and may enhance intervention designs. We investigate the behavior of OCD patients with respect to HCs by means of decision making economic models within a typical neuropsychological setting, such as the Cambridge Gambling Task. In this task subjects have to decide the amount of their initial wealth to invest in each risky decision. To account for heterogenous preferences, we have analyzed the micro-level data for a more informative analysis of the choices made by the subjects. We consider two influential models in economics: the expected value (EV), which assumes risk neutrality, and a multiple reference points model, an alternative formulation of Disappointment theory. We find evidence that (medicated) OCD patients are more consistent with EV than HCs. The former appear to be more risk neutral, namely, less sensitive to risk than HCs. They also seem to base their decisions on disappointment avoidance less than HCs.

Decision-making ability in psychosis: a systematic review and meta-analysis of the magnitude, specificity and correlates of impaired performance on the Iowa and Cambridge Gambling Tasks

To identify factors which may help or hinder decision-making ability in people with psychosis, we did a systematic review and meta-analysis of their performance on the Iowa and Cambridge Gambling Tasks. Analysis of 47 samples found they had moderately poorer performance than healthy individuals (N = 4264, g = -0.57, 95% confidence interval (CI) -0.66 to -0.48). Few studies (k = 8) used non-psychotic clinical comparator groups, although very low-quality evidence (k = 3) found people with bipolar disorder may perform better. Negative symptoms (k = 13, N = 648, r = -0.17, 95% CI -0.26 to -0.07) and lower IQ (k = 11, N = 525, r = 0.20, 95% CI 0.29-0.10), but not positive symptoms (k = 10, N = 512, r = -0.01, 95% CI -0.11 to 0.08), each had small-moderate associations with poorer decision-making. Lower quality evidence suggested general symptoms, working memory, social functioning, awareness of emotional responses to information, and attentional bias towards gain are associated with decision-making, but not education, executive functioning or overall symptoms. Meta-regression suggested an inverse association between decision-making and depression severity (k = 6, Q = 6.41, R2 100%, p = 0.01). Those taking first-generation (k = 6, N = 305, g = -0.17, 95% CI -0.40 to 0.06, p = 0.147) or low-dose antipsychotics (k = 5, N = 442, g = -0.19, 95% CI -0.44 to 0.06, p = 0.139) had unimpaired decision-making. Although meta-regression found no linear association between dose and performance, non-reporting of the dose was common and associated with larger impairments (k = 46, Q = 4.71, R2 14%, p = 0.03). Those supporting people with psychosis to make decisions, including treatment decisions, should consider the potential effect of these factors. Interventionist-causal trials are required to test whether reducing antipsychotic dose and treating anxiety and depression can improve decision-making in this group.

Current Status of Cognitive Remediation for Psychiatric Disorders: A Review

Cognition is an important factor that affects daily functioning and quality of life. Impairment in cognitive function is a common symptom present in various psychological disorders, which hinders patients from functioning normally. Given that cognitive impairment has devastating effects, enhancing this in patients should lead to improvements in compromised quality of life and functioning, including vocational functioning. Over the past 50 years, several attempts have been made to improve impaired cognition, and empirical evidence for cognitive remediation (CR) has accumulated that supports its efficacy for treating schizophrenia. More recently, CR has been successfully applied in the treatment of depressive disorders, bipolar disorders, attention deficit/hyperactivity disorder, and anorexia nervosa. This study critically reviews recent CR studies and suggests their future direction. This study aimed to provide a modern definition of CR, and examine the current status of empirical evidence and representative CR programs that are widely used around the world.

The morphometric co-atrophy networking of schizophrenia, autistic and obsessive spectrum disorders

By means of a novel methodology that can statistically derive patterns of co-alterations distribution from voxel-based morphological data, this study analyzes the patterns of brain alterations of three important psychiatric spectra-that is, schizophrenia spectrum disorder (SCZD), autistic spectrum disorder (ASD), and obsessive-compulsive spectrum disorder (OCSD). Our analysis provides five important results. First, in SCZD, ASD, and OCSD brain alterations do not distribute randomly but, rather, follow network-like patterns of co-alteration. Second, the clusters of co-altered areas form a net of alterations that can be defined as morphometric co-alteration network or co-atrophy network (in the case of gray matter decreases). Third, within this network certain cerebral areas can be identified as pathoconnectivity hubs, the alteration of which is supposed to enhance the development of neuronal abnormalities. Fourth, within the morphometric co-atrophy network of SCZD, ASD, and OCSD, a subnetwork composed of eleven highly connected nodes can be distinguished. This subnetwork encompasses the anterior insulae, inferior frontal areas, left superior temporal areas, left parahippocampal regions, left thalamus and right precentral gyri. Fifth, the co-altered areas also exhibit a normal structural covariance pattern which overlaps, for some of these areas (like the insulae), the co-alteration pattern. These findings reveal that, similarly to neurodegenerative diseases, psychiatric disorders are characterized by anatomical alterations that distribute according to connectivity constraints so as to form identifiable morphometric co-atrophy patterns.

Anhedonia in depression and schizophrenia: A transdiagnostic challenge

BACKGROUND

Anhedonia, as a dysregulation of the reward circuit, is present in both Major Depressive Disorder (MDD) and schizophrenia (SZ).

AIMS

To elucidate the clinical and neurobiological differences between schizophrenia (SZ) and depression (MDD) in regard to anhedonia, while reconciling the challenges and benefits of assessing anhedonia as a transdiagnostic feature under the Research Domain Criteria (RDoC) framework.

METHODS

In this review, we summarize data from publications examining anhedonia or its underlying reward deficits in SZ and MDD. A literature search was conducted in OVID Medline, PsycINFO and EMBASE databases between 2000 and 2017.

RESULTS

While certain subgroups share commonalities, there are also important differences. SZ may be characterized by a disorganization, rather than a deficiency, in reward processing and cognitive function, including inappropriate energy expenditure and focus on irrelevant cues. In contrast, MDD has been characterized by deficits in anticipatory pleasure, development of reward associations, and integration of information from past experience. Understanding the roles of neurotransmitters and aberrant brain circuitry is necessary to appreciate differences in reward function in SZ and MDD.

CONCLUSION

Anhedonia as a clinical presentation of reward circuit dysregulation is an important and relatively undertreated symptom of both SZ and MDD. In order to improve patient outcomes and quality of life, it is important to consider how anhedonia fits into both diagnoses.

Obsessive-compulsive symptoms and overall psychopathology in psychotic disorders: longitudinal assessment of patients and siblings

The course of obsessive-compulsive symptoms (OCS) and its association with alterations in other clinical variables in patients with psychotic disorders is insufficiently known. Patients (n = 602) and unaffected siblings (n = 652) from the Dutch Genetic Risk and Outcome of Psychosis (GROUP) study were investigated at baseline and after 3 years. Participants were assigned to four groups based on the course of OCS over time: no-OCS, persistent OCS, initial OCS and de novo OCS. In addition to cross-sectional comparisons, longitudinal associations between changes in OCS and symptoms of schizophrenia and general functioning were investigated. Patients with co-occurring OCS reported significantly higher severity of psychotic and affective symptoms as well as lower overall functioning compared to patients without OCS. These differences were stable over time for patients reporting persistent OCS. Subsequent repeated measure analysis revealed significant interaction effects for groups reporting changes in their OCS. Whereas the group with remission of initial OCS showed significant improvement in positive symptoms, emotional distress and functioning, the de novo group showed no significant change in these variables, but rather reported stable higher psychopathology. Similar results were found on a subclinical level in siblings. Patients with co-occurring OCS present a more severe clinical picture, especially if symptoms persist over time. The remission of OCS was associated with overall improvement, whereas individuals with de novo OCS already reported higher clinical impairment before OCS onset. More research is needed to elucidate causal pathways and to develop effective interventions for persistent comorbid OCS.

Shared and Disorder-Specific Neurocomputational Mechanisms of Decision-Making in Autism Spectrum Disorder and Obsessive-Compulsive Disorder

Autism spectrum disorder (ASD) and obsessive-compulsive disorder (OCD) often share phenotypes of repetitive behaviors, possibly underpinned by abnormal decision-making. To compare neural correlates underlying decision-making between these disorders, brain activation of boys with ASD (N = 24), OCD (N = 20) and typically developing controls (N = 20) during gambling was compared, and computational modeling compared performance. Patients were unimpaired on number of risky decisions, but modeling showed that both patient groups had lower choice consistency and relied less on reinforcement learning compared to controls. ASD individuals had disorder-specific choice perseverance abnormalities compared to OCD individuals. Neurofunctionally, ASD and OCD boys shared dorsolateral/inferior frontal underactivation compared to controls during decision-making. During outcome anticipation, patients shared underactivation compared to controls in lateral inferior/orbitofrontal cortex and ventral striatum. During reward receipt, ASD boys had disorder-specific enhanced activation in inferior frontal/insular regions relative to OCD boys and controls. Results showed that ASD and OCD individuals shared decision-making strategies that differed from controls to achieve comparable performance to controls. Patients showed shared abnormalities in lateral-(orbito)fronto-striatal reward circuitry, but ASD boys had disorder-specific lateral inferior frontal/insular overactivation, suggesting that shared and disorder-specific mechanisms underpin decision-making in these disorders. Findings provide evidence for shared neurobiological substrates that could serve as possible future biomarkers.

Effects of Anterior Capsulotomy on Decision Making in Patients with Refractory Obsessive-Compulsive Disorder

Despite various lines of evidence implicating impaired decision-making ability in individuals with obsessive–compulsive disorder (OCD), neuropsychological investigation has generated inconsistent findings. Although the cortico-striato-thalamo-cortical (CSTC) circuitry has been suggested, the involvement of the cortex has not yet been fully demonstrated. Moreover, it is unknown whether surgical intervention on the CSTC circuitry results in a predicted improvement of decision-making ability of OCD. Here we present a study of decision making based on the Iowa Gambling Task (IGT) to investigate decision making in a large sample of individuals with treatment-resistant OCD with and without anterior capsulotomy (AC). Task performance was evaluated in healthy subjects, individuals with OCD that had not undergone surgery, and postsurgical OCD patients with AC. The latter group was further divided into a short-term postsurgical group and a long-term postsurgical group. We found that the OCD patients without surgery performed significantly worse than the healthy controls on the IGT. There were no significant differences in decision-making between the presurgical OCD patients and those at the short-term postsurgical follow-up. Decision-making ability of the long-term postsurgical OCD patients was improved to the level comparable to that of healthy controls. All clinical symptoms (OCD, depression, and anxiety) assessed by psychiatric rating scales were significantly alleviated post-surgically, but exhibited no correlation with their IGT task performance. Our findings provide strong evidence that OCD is linked to impairments in decision-making ability; that impaired CSTC circuitry function is directly involved in the manifestation of OCD; and that AC related improvements in cognitive functions are caused by long-term plasticity in the brain circuitry.

Risky decision-making under risk in schizophrenia: A deliberate choice?

BACKGROUND AND OBJECTIVES

Patients with schizophrenia reveal impaired decision-making strategies causing social, financial and health care problems. The extent to which deficits in decision-making reflect intentional risky choices in schizophrenia is still under debate. Based on previous studies we expected patients with schizophrenia to reveal a riskier performance on the GDT and to make more disadvantageous decisions on the IGT.

METHODS

In the present study, we investigated 38 patients with schizophrenia and 38 matched healthy control subjects with two competing paradigms regarding feedback: (1) The Game of Dice Task (GDT), in which the probabilities of winning or losing are stable and explicitly disclosed to the subject, to assess decision-making under risk and (2) the Iowa Gambling Task (IGT), which requires subjects to infer the probabilities of winning or losing from feedback, to investigate decision-making under ambiguity.

RESULTS

Patients with schizophrenia revealed an overall riskier performance on the GDT; although they adjusted their strategy over the course of the GDT, they still made significantly more disadvantageous choices than controls. More positive symptoms in patients with schizophrenia indicated by higher PANSS positive scores were associated with riskier choices and less use of negative feedback. Compared to healthy controls, they were not impaired in net score but chose more disadvantageous cards than controls on the first block of the IGT.

LIMITATIONS

Effects of medication at the time of testing cannot be ruled out.

CONCLUSIONS

Our findings suggest that patients with schizophrenia make riskier decisions and are less able to regulate their decision-making to implement advantageous strategies, even when the probabilities of winning or losing are explicitly disclosed. The dissociation between performance on the GDT and IGT suggests a pronounced impairment of executive functions related to the dorsolateral prefrontal cortex.

Schizo-obsessive spectrum disorders: an update

The presence of obsessive-compulsive symptoms (OCS) and obsessive-compulsive disorders (OCD) in schizophrenia is frequent, and a new clinical entity has been proposed for those who show the dual diagnosis: the schizo-obsessive disorder. This review scrutinizes the literature across the main academic databases, and provides an update on different aspects of schizo-obsessive spectrum disorders, which include schizophrenia, schizotypal personality disorder (SPD) with OCD, OCD with poor insight, schizophrenia with OCS, and schizophrenia with OCD (schizo-obsessive disorder). An epidemiological discussion on the discrepancies observed in the prevalence of OCS and OCD in schizophrenia across time is provided, followed by an overview of the main clinical and phenomenological features of the disorder in comparison to the primary conditions under a spectral perspective. An updated and comparative analysis of the main genetic, neurobiological, neurocognitive, and pharmacological treatment aspects for the schizo-obsessive spectrum is provided, and a discussion on endophenotypic markers is introduced in order to better understand its substrate. There is sufficient evidence in the literature to demonstrate the clinical relevance of the schizo-obsessive spectrum, although little is known about the neurobiology, genetics, and neurocognitive aspects of these groups. The pharmacological treatment of these patients is still challenging, and efforts to search for possible specific endophenotypic markers would open new avenues in the knowledge of schizo-obsessive spectrum.

Steeper discounting of delayed rewards in schizophrenia but not first-degree relatives

Excessive discounting of future rewards has been related to a variety of risky behaviors and adverse clinical conditions. Prior work examining delay discounting in schizophrenia suggests an elevated discount rate. However, it remains uncertain whether this reflects the disease process itself or an underlying genetic vulnerability, whether it is selective for delay discounting or reflects pervasive changes in decision-making, and whether it is driven by specific clinical dimensions such as cognitive impairment. Here we investigated delay discounting, as well as loss aversion and risk aversion, in three groups: schizophrenia (SZ), unaffected first-degree family members (FM), and controls without a family history of psychosis (NC). SZ had elevated discounting, without changes in loss aversion or risk aversion. Contrary to expectations, the FM group did not show an intermediate phenotype in discounting. Higher discount rates correlated with lower cognitive performance on verbal reasoning, but this did not explain elevated discount rates in SZ. Group differences were driven primarily by the non-smoking majority of the sample. This study provides further evidence for elevated discounting in schizophrenia, and demonstrates that steeper discounting is not necessarily associated with familial risk, cannot be wholly accounted for by cognitive deficits, and is not attributable to smoking-related impulsivity.

A study of cognitive function in treatment-refractory obsessive-compulsive disorder treated with capsulotomy

OBJECTIVE Anterior capsulotomy (AC) is sometimes used as a last resort for treatment-refractory obsessive-compulsive disorder (OCD). Previous studies assessing neuropsychological outcomes in patients with OCD have identified several forms of cognitive dysfunction that are associated with the disease, but few have focused on changes in cognitive function in OCD patients who have undergone surgery. In the present study, the authors investigated the effects of AC on the cognitive function of patients with treatment-refractory OCD. METHODS The authors selected 14 patients with treatment-refractory OCD who had undergone bilateral AC between 2007 and 2013, 14 nonsurgically treated OCD patients, and 14 healthy control subjects for this study. The 3 groups were matched for sex, age, and education. Several neuropsychological tests, including Similarities and Block Design, which are subsets of the Wechsler Abbreviated Scale of Intelligence; Immediate and Delayed Logical Memory and Immediate and Delayed Visual Reproduction, which are subsets of the Wechsler Memory Scale-Revised; and Corrects, Categories, Perseverative Errors, Nonperseverative Errors, and Errors, subtests of the Wisconsin Card Sorting Test, were conducted in all 42 subjects at baseline and after AC, after nonsurgical treatment, or at 6-month intervals, as appropriate. The Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) was used to measure OCD symptoms in all 28 OCD patients. RESULTS The Y-BOCS scores decreased significantly in both OCD groups during the 12-month follow-up period. Surgical patients showed higher levels of improvement in verbal memory, visual memory, visuospatial skills, and executive function than the nonsurgically treated OCD patients. CONCLUSIONS The findings of this study suggest that AC not only reduces OCD symptoms but also attenuates moderate cognitive deficits.

The neural underpinnings of cognitive flexibility and their disruption in psychotic illness

Schizophrenia (SZ) has long been associated with a variety of cognitive deficits, including reduced cognitive flexibility. More recent findings, however, point to tremendous inter-individual variability among patients on measures of cognitive flexibility/set-shifting. With an eye toward shedding light on potential sources of variability in set-shifting abilities among SZ patients, I examine the neural substrates of underlying probabilistic reversal learning (PRL) - a paradigmatic measure of cognitive flexibility - as well as neuromodulatory influences upon these systems. Finally, I report on behavioral and neuroimaging studies of PRL in SZ patients, discussing the potentially influences of illness profile and antipsychotic medications on cognitive flexibility in SZ.

Pick a Card, Any Card: The Relationship Between Anxiety, Obsessive-Compulsive Symptoms and Decision-Making

Specific deficits in decision-making have been demonstrated in patients with obsessive-compulsive disorder (OCD). The experience of anxious arousal in obsessive-compulsive (OC) patients has been posited to be responsible for disrupting the cognitive processes that lead to efficacious decision-making (Sachdev & Malhi, 2005). In spite of this, research has neglected to examine explicitly the effect of anxiety on the relationship between decision-making and OCD. The current study investigates whether decision-making differences on the Iowa Gambling Task (IGT) occur as a function of OC symptomatology in a non-clinical sample (n = 110). Participants were randomly allocated to either an anxiety condition (n = 58) or control condition (n = 52). Anxious arousal was induced in the anxiety condition via an experimental manipulation prior to commencing the IGT. Participants in the anxiety condition performed significantly worse than those in the control group on the IGT. However, OC symptomatology did not significantly predict IGT performance. The experience of anxiety did not significantly moderate the relationship between OC symptomatology and IGT performance. These findings indicate that decision-making differences do not occur as a function of OC symptomatology in a non-clinical sample; however, they do suggest that the experience of anxiety significantly impairs decision-making performance. The theoretical and practical applications of the findings are discussed.

Trait-related decision making impairment in obsessive-compulsive disorder: evidence from decision making under ambiguity but not decision making under risk

This study aimed to investigate whether deficits in decision making were potential endophenotype markers for OCD considering different phases of the disease. Fifty-seven non-medicated OCD patients (nmOCD), 77 medicated OCD patients (mOCD), 48 remitted patients with OCD (rOCD) and 115 healthy controls were assessed with the Iowa Gambling Task (IGT), which measured decision making under ambiguity, and the Game of Dice Task (GDT), which measured decision making under risk. While the three patients groups showed impaired performance on the IGT compared with healthy controls, all patients showed intact performance on the GDT. Furthermore, the rOCD patients showed a preference for deck B, indicating that they showed more sensitivity to the frequency of loss than to the magnitude of loss, whereas the mOCD patients showed a preference for deck A, indicating that they had more sensitivity to the magnitude of loss than to the frequency of loss. These data suggested that OCD patients had trait-related impairments in decision making under ambiguity but not under risk, and that dissociation of decision making under ambiguity and under risk is an appropriate potential neurocognitive endophenotype for OCD. The subtle but meaningful differences in decision making performance between the OCD groups require further study.

Decision-making under uncertainty in obsessive-compulsive disorder

Obsessive compulsive disorder (OCD) produces profound morbidity. Difficulties with decision-making and intolerance of uncertainty are prominent clinical features in many patients. The nature and etiology of these deficits are poorly understood. We used a well-validated choice task, grounded in behavioral economic theory, to investigate differences in valuation and value-based choice during decision making under uncertainty in 20 unmedicated participants with OCD and 20 matched healthy controls. Participants' choices were used to assess individual decision-making characteristics. OCD participants did not differ from healthy controls in how they valued uncertain options when outcome probabilities were known (risk) but were more likely than healthy controls to avoid uncertain options when these probabilities were imprecisely specified (ambiguity). Compared to healthy controls, individuals with OCD were less consistent in their choices and less able to identify options that should be clearly preferable. These abnormalities correlated with symptom severity. These results suggest that value-based choices during decision-making are abnormal in OCD. Individuals with OCD show elevated intolerance of uncertainty, but only when outcome probabilities are themselves uncertain. Future research focused on the neural valuation network, which is implicated in value-based computations, may provide new neurocognitive insights into the pathophysiology of OCD. Deficits in decision-making processes may represent a target for therapeutic intervention.

Similarities and Differences in Decision-Making Impairments between Autism Spectrum Disorder and Schizophrenia

Although individuals with autism spectrum disorders (ASD) and schizophrenia (SCH) share overlapping characteristics and may perform similarly on many cognitive tasks, cognitive dysfunctions common to both disorders do not necessarily share the same underlying mechanisms. Decision-making is currently a major research interest for both ASD and SCH. The aim of the present study was to make direct comparisons of decision-making and disorder-specific underlying neuropsychological mechanisms between the two disorders. Thirty-seven participants with ASD, 46 patients with SCH, and 80 healthy controls (HC) were assessed with the Iowa Gambling Task (IGT), which measures decision-making under ambiguity, and the Game of Dice Task (GDT), which measures decision-making under risk. The results revealed that both the ASD and SCH groups had deficits for both the IGT and the GDT compared with the HC. More importantly, in the IGT, participants with ASD displayed a preference for deck A, indicating that they had more sensitivity to the magnitude of loss than to the frequency of loss, whereas patients with SCH displayed a preference for deck B, indicating that they showed more sensitivity to the frequency of loss than to the magnitude of loss. In the GDT, the impaired performance might be due to the deficits in executive functions in patients with SCH, whereas the impaired performance might be due to the deficits in feedback processing in participants with ASD. These findings demonstrate that there are similar impairments in decision-making tasks between ASD and SCH; however, these two disorders may have different impairment mechanisms.

Evaluating effect of symptoms heterogeneity on decision-making ability in obsessive-compulsive disorder

AIMS

Despite having a univocal definition, obsessive-compulsive disorder (OCD) shows a remarkably phenotypic heterogeneity. The published reports show impaired decision-making in OCD patients, using tasks such as the Iowa Gambling Task (IGT). We wanted to verify the hypothesis of an IGT worse performance in a large sample of OCD patients and healthy control (HC) subjects and to examine the relation between neuropsychological performance in IGT and the OCD symptoms heterogeneity.

METHODS

Binary data from the Yale-Brown Obsessive Compulsive Scale collected on a large sample of OCD patients were analyzed using a multidimensional item response theory model to explore the underlying structure of data, thus revealing latent factors. Factor scores were categorized into quartiles. Then, for each factor, we identified patients respectively with the highest versus lowest score. We evaluated whether symptom dimensions affect the probability of a correct answer over time generalized, during IGT performance, fitting a generalized linear mixed model.

RESULTS

We found a general deficit in ambiguous decision-making in OCD compared to HC. Moreover, our findings suggested that OCD symptoms heterogeneity affects decision-making learning abilities during IGT. In fact, while 'Symmetry' and 'Washing' patients showed a learning curve during the task, other subgroups did not.

CONCLUSIONS

Our study confirmed previous findings suggesting that OCD is characterized by a deficit in decision-making under uncertainty. Moreover, our study gave evidence about biological specificity for each symptom dimension in OCD. Data were discussed in the context of the somatic marker hypothesis, which was hypothesized to be reduced in OCD patients.

Integrating frequency and magnitude information in decision-making in schizophrenia: An account of patient performance on the Iowa Gambling Task

BACKGROUND

The Iowa Gambling Task (IGT; Bechara et al., 1994) has frequently been used to assess risky decision making in clinical populations, including patients with schizophrenia (SZ). Poor performance on the IGT is often attributed to reduced sensitivity to punishment, which contrasts with recent findings from reinforcement learning studies in schizophrenia.

METHODS

In order to investigate possible sources of IGT performance deficits in SZ patients, we combined data from the IGT from 59 SZ patients and 43 demographically-matched controls with data from the Balloon Analog Risk Task (BART) in the same participants. Our analyses sought to specifically uncover the role of punishment sensitivity and delineate the capacity to integrate frequency and magnitude information in decision-making under risk.

RESULTS

Although SZ patients, on average, made more choices from disadvantageous decks than controls did on the IGT, they avoided decks with frequent punishments at a rate similar to controls. Patients also exhibited excessive loss-avoidance behavior on the BART.

CONCLUSIONS

We argue that, rather than stemming from reduced sensitivity to negative consequences, performance deficits on the IGT in SZ patients are more likely the result of a reinforcement learning deficit, specifically involving the integration of frequencies and magnitudes of rewards and punishments in the trial-by-trial estimation of expected value.

Neuropsychological and Clinical Profiles of Children and Adolescents Diagnosed with Childhood Obsessive Compulsive Disorder

INTRODUCTION

The differential features of childhood-onset obsessive compulsive disorder (OCD) compared to adult-onset OCD are being more of a focus of attention in recent years. The aim of this study was to determine the clinical and neuropsychological profiles of children and adolescents diagnosed with childhood-onset OCD and to investigate the association between the duration, severity, comorbidity, and family history of the disorder and clinical and neuropsychological functional impairments.

METHODS

Thirty-five OCD patients (patient group) and 35 healthy control subjects (control group) between 8-15 years of age were included. To investigate the neuropsychological profiles, the Wisconsin Card Sorting Test (WCST), Stroop Test, and Continuous Performance Test (CPT) were applied. To assess the clinical and behavioral profiles, the Children's Depression Inventory (CDI), Conner's Parent Rating Scale (CPRS-48), and the Yale Brown Obsessive Compulsive Scale (YB-OCS) and Yale Global Tic Severity Rating Scale (YGTSRS) were given.

RESULTS

Based on the performance in the WCST, Stroop Test, and SPT, the results of the study reveal that childhood-onset OCD patients have statistically significant worse performance compared to healthy controls in terms of executive functions, sustained attention, and motor inhibition tasks. Excluding the comorbid diagnoses, childhood-onset OCD patients did not show a difference in behavioral problems, but they had higher levels of anxiety compared to healthy controls.

CONCLUSION

The findings of this study reveal that independent of the duration, severity, comorbid problems, and anxiety levels, the disorder itself is associated with worse performance in executive functions, attention, and motor inhibition processes, and a positive family history of OCD is an important risk factor. Long-term follow-up studies with patients diagnosed with childhood-onset OCD would be a logical next step in order to determine the cause-effect relation between the disorder and cognitive impairments.

Second generation antipsychotic-induced obsessive-compulsive symptoms in schizophrenia: a review of the experimental literature

Second generation antipsychotics (SGAs) have been implicated in the de novo emergence and exacerbation of obsessive-compulsive symptoms (OCS) in patients with schizophrenia. Among SGAs, clozapine, olanzapine, and risperidone are the most prominent agents associated with these sequelae, according to case reports. Comorbid OCS can impede recovery by compromising treatment benefits, medication compliance, and clinical prognoses. Previous reviews of SGA-induced OCS have predominantly focused on descriptive case reports, with limited attention paid toward experimental findings. To address this paucity of data, we sought to review the effects of SGAs on OCS in schizophrenia in the experimental literature, while addressing the role of different treatment (duration, dose, serum levels) and pharmacogenetic factors. Our findings suggest that clozapine confers the greatest risk of OCS in schizophrenia, with 20 to 28% of clozapine-treated patients experiencing de novo OCS, in addition to 10 to 18% incurring an exacerbation of pre-existing OCS. Clozapine can also yield full threshold obsessive-compulsive disorder (OCD), in some cases. Olanzapine is another high risk drug for secondary OCS which occurs in 11 to 20% of schizophrenic patients receiving olanzapine therapy. At this time, there is insufficient experimental evidence to characterize the effects of other SGAs on OCS. Despite some experimental support for the involvement of longer treatment duration and genetic factors in mediating drug-induced OCS, more research is needed to clearly elucidate these associations. Based on these results, schizophrenic patients should be routinely monitored for OCS throughout the course of SGA treatment, particularly when clozapine or olanzapine is administered.

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.

The neuropsychology of male adults with high-functioning autism or asperger syndrome

Autism Spectrum Disorder (ASD) is diagnosed on the basis of behavioral symptoms, but cognitive abilities may also be useful in characterizing individuals with ASD. One hundred seventy-eight high-functioning male adults, half with ASD and half without, completed tasks assessing IQ, a broad range of cognitive skills, and autistic and comorbid symptomatology. The aims of the study were, first, to determine whether significant differences existed between cases and controls on cognitive tasks, and whether cognitive profiles, derived using a multivariate classification method with data from multiple cognitive tasks, could distinguish between the two groups. Second, to establish whether cognitive skill level was correlated with degree of autistic symptom severity, and third, whether cognitive skill level was correlated with degree of comorbid psychopathology. Fourth, cognitive characteristics of individuals with Asperger Syndrome (AS) and high-functioning autism (HFA) were compared. After controlling for IQ, ASD and control groups scored significantly differently on tasks of social cognition, motor performance, and executive function (P's < 0.05). To investigate cognitive profiles, 12 variables were entered into a support vector machine (SVM), which achieved good classification accuracy (81%) at a level significantly better than chance (P < 0.0001). After correcting for multiple correlations, there were no significant associations between cognitive performance and severity of either autistic or comorbid symptomatology. There were no significant differences between AS and HFA groups on the cognitive tasks. Cognitive classification models could be a useful aid to the diagnostic process when used in conjunction with other data sources—including clinical history. Autism Res2014, 7: 568–581. © 2014 International Society for Autism Research, Wiley Periodicals, Inc.

Review of cognitive performance in hoarding disorder

Hoarding disorder is characterized by extreme difficulty letting go of objects other people would routinely discard or give away, such that the home becomes dysfunctionally cluttered with possessions. Specific cognitive processes, such as decision-making, categorization, and attention, have been hypothesized to contribute to the overvaluing of objects. This review synthesizes the evidence related to those propositions and other executive functioning processes that have received research attention. In this paper, we are primarily interested in cognitive processes that can be, but are not always, studied using performance tasks. Compared to both healthy controls and clinical controls, participants with clinical levels of compulsive hoarding show replicable performance deficits in several areas: planning/problem-solving decisions, visuospatial learning and memory, sustained attention/working memory, and organization. Categorization/concept formation, visuospatial processing, and inhibitory control require further investigation and more detailed testing methods to address inconsistencies in reported findings. Many studies fail to account for potential confounds presented by comorbid depression and between-group differences in age, a problem that should be rectified in future research on this topic. The article concludes with recommendations for a research agenda to better understand contributors to abnormal valuing of objects in hoarding disorder.

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.

Morphologic and functional connectivity alterations of corticostriatal and default mode network in treatment-naïve patients with obsessive-compulsive disorder

Background

Previous studies have demonstrated that structural deficits and functional connectivity imbalances might underlie the pathophysiology of obsessive-compulsive disorder (OCD). The purpose of the present study was to investigate gray matter deficits and abnormal resting-state networks in patients with OCD and further investigate the association between the anatomic and functional alterations and clinical symptoms.

Methods

Participants were 33 treatment-naïve OCD patients and 33 matched healthy controls. Voxel-based morphometry was used to investigate the regions with gray matter abnormalities and resting-state functional connectivity analysis was further conducted between each gray matter abnormal region and the remaining voxels in the brain.

Results

Compared with healthy controls, patients with OCD showed significantly increased gray matter volume in the left caudate, left thalamus, and posterior cingulate cortex, as well as decreased gray matter volume in the bilateral medial orbitofrontal cortex, left anterior cingulate cortex, and left inferior frontal gyrus. By using the above morphologic deficits areas as seed regions, functional connectivity analysis found abnormal functional integration in the cortical-striatum-thalamic-cortical (CSTC) circuits and default mode network. Subsequent correlation analyses revealed that morphologic deficits in the left thalamus and increased functional connectivity within the CSTC circuits positively correlated with the total Y-BOCS score.

Conclusion

This study provides evidence that morphologic and functional alterations are seen in CSTC circuits and default mode network in treatment-naïve OCD patients. The association between symptom severity and the CSTC circuits suggests that anatomic and functional alterations in CSTC circuits are especially important in the pathophysiology of OCD.

Cognitive deficits of executive functions and decision-making in obsessive-compulsive disorder

The nature of cognitive deficits in obsessive-compulsive disorder (OCD) is characterized by contradictory findings in terms of specific neuropsychological deficits. Selective impairments have been suggested to involve visuospatial memory, set shifting, decision-making and response inhibition. The aim of this study was to investigate cognitive deficits in decision-making and executive functioning in OCD. It was hypothesized that the OCD patients would be less accurate in their responses compared to the healthy controls in rational decision-making on a version of the Cambridge gambling task (CGT) and on the color-word interference test and on a version of the Tower of Hanoi test (tower test) of executive functioning. Thirteen participants with OCD were compared to a group of healthy controls (n = 13) matched for age, gender, education and verbal IQ. Results revealed significant differences between the OCD group and the healthy control group on quality of decision-making on the CGT and for achievement score on the tower test. On these two tasks the OCD group performed worse than the healthy control group. The symptom-dimension analysis revealed performance differences where safety checking patients were impaired on the tower test compared to contamination patients. Results are discussed in the framework of cognition and emotion processing and findings implicate that OCD models should address, specifically, the interaction between cognition and emotion. Here the emotional disruption hypothesis is forwarded to account for the dysfunctional behaviors in OCD. Further implications regarding methodological and inhibitory factors affecting cognitive information processing are highlighted.

Decision-making and impulsivity in eating disorder patients

Impairment in decision-making can be related to some pathological behaviors in eating disorders. This ability was assessed in 71 eating disorder patients (27 restricting type patients and 44 binge/purging type patients) and compared with 38 healthy controls using the Iowa Gambling Task. This task simulates real-life decision-making by assessing the ability to sacrifice immediate rewards in favor of long term gains. Furthermore, some studies have demonstrated a relationship between impulsivity and decision-making, so in our study the Barratt Impulsiveness Scale was also used. Eating disorder patients, both the restricting and the binge/purging groups, performed poorly in the Iowa Gambling Task compared to controls, confirming a deficit in decision-making in these patients. The restricting group showed poorer IGT performance than the binge/purging group. Interestingly, impulsivity was negatively correlated with decision-making, but only in the binge/purging group. In conclusion, our results confirm a specific deficit in eating disorder patients which may be related to their pathological eating behavior, and suggest that this impairment might be explained by different mechanisms in restricting and binge/purging disorders.

A further evaluation of decision-making under risk and under ambiguity in schizophrenia

Abnormal decision-making has been described as a key-concept to understand some behavioral disturbances in schizophrenia. However, whether schizophrenia patients display impairments in profitable decision-making on experimental designs is still controversial (1) to assess performance on decision-making paradigms under ambiguity and under risk conditions in a large sample of schizophrenia patients and (2) to study the impact of clinical variables on decision-making performance in schizophrenia. The Iowa gambling task (IGT) and the game of dice task (GDT) were administered to assess, respectively, decision-making under ambiguity and under risk in 63 schizophrenia patients and 67 healthy controls. In addition, clinical variables (e.g., schizophrenic symptoms, self-reported depression, and impulsivity) were evaluated using appropriate questionnaires the same day. Pharmacological treatments were reported. Schizophrenia patients had impaired performances on both IGT and GDT tasks. No correlation between the decision-making tasks performance and clinical variables was found. Lower gains on the GDT were associated with executive dysfunctioning in schizophrenia. These findings give evidence that schizophrenia patients display impairments in both decision-making under ambiguity and under risk.

Increased salience of gains versus decreased associative learning differentiate bipolar disorder from schizophrenia during incentive decision making

BACKGROUND

Abnormalities in incentive decision making, typically assessed using the Iowa Gambling Task (IGT), have been reported in both schizophrenia (SZ) and bipolar disorder (BD). We applied the Expectancy-Valence (E-V) model to determine whether motivational, cognitive and response selection component processes of IGT performance are differentially affected in SZ and BD.

METHOD

Performance on the IGT was assessed in 280 individuals comprising 70 remitted patients with SZ, 70 remitted patients with BD and 140 age-, sex- and IQ-matched healthy individuals. Based on the E-V model, we extracted three parameters, 'attention to gains or loses', 'expectancy learning' and 'response consistency', that respectively reflect motivational, cognitive and response selection influences on IGT performance.

RESULTS

Both patient groups underperformed in the IGT compared to healthy individuals. However, the source of these deficits was diagnosis specific. Associative learning underlying the representation of expectancies was disrupted in SZ whereas BD was associated with increased incentive salience of gains. These findings were not attributable to non-specific effects of sex, IQ, psychopathology or medication.

CONCLUSIONS

Our results point to dissociable processes underlying abnormal incentive decision making in BD and SZ that could potentially be mapped to different neural circuits.

Practitioner review: do performance-based measures and ratings of executive function assess the same construct?

BACKGROUND

Both performance-based and rating measures are commonly used to index executive function in clinical and neuropsychological assessments. They are intended to index the same broad underlying mental construct of executive function. The association between these two types of measures was investigated in the current article.

METHOD AND RESULTS

We examined the association between performance-based and rating measures of executive function in 20 studies. These studies included 13 child and 7 adult samples, which were derived from 7 clinical, 2 nonclinical, and 11 combined clinical and nonclinical samples. Only 68 (24%) of the 286 relevant correlations reported in these studies were statistically significant, and the overall median correlation was only .19.

CONCLUSIONS

It was concluded that performance-based and rating measures of executive function assess different underlying mental constructs. We discuss how these two types of measures appear to capture different levels of cognition, namely, the efficiency of cognitive abilities and success in goal pursuit. Clinical implications of using performance-based and rating measures of executive function are discussed, including the use of these measures in assessing ADHD.

Poor performance on the Iowa gambling task in children with obsessive-compulsive disorder

BACKGROUND

Several lines of evidence implicate orbitofrontal cortex dysfunction in the pathophysiology of obsessive-compulsive disorder (OCD). The purpose of this study was to investigate neuropsychological dysfunction of the orbitofrontal cortex in children with OCD.

METHODS

The Iowa Gambling Task (IGT), which reflects orbitofrontal cortex function, and the Wisconsin Card Sorting Test (WCST), which is associated with functioning of the dorsolateral prefrontal cortex, were administered to 22 children with OCD and 22 healthy controls matched for gender, age, and intelligence.

RESULTS

OCD patients displayed poor performance on the IGT. In contrast, performance on the WCST was not impaired in OCD patients compared to controls.

CONCLUSIONS

These findings are in line with previous studies demonstrating that OCD in childhood is associated with a dysfunction of orbitofrontal-striatal-thalamic circuitry.

[Decision-making and schizophrenia]

Abnormalities involving the prefrontal cortex (PFC) have long been postulated to underpin the pathophysiology of schizophrenia. Investigations of PFC integrity have focused mainly on the dorsolateral PFC (DLPFC) and abnormalities in this region have been extensively documented. However, defects in schizophrenia may extend to other prefrontal regions, including the ventromedial PFC (VMPFC), and evidence of VMPFC abnormalities comes from neuropathological, structural and functional studies. Patients with acquired brain injury to the VMPFC display profound disruption of social behaviour and poor judgment in their personal lives. The Iowa Gambling Task (IGT) was developed to assess decision-making in these neurological cases : it presents a series of 100 choices from four card decks that differ in the distribution of rewarding and punishing outcomes. Whilst healthy volunteers gradually develop a preference for the two "safe" decks over the course of the task, patients with VMPFC lesions maintain a preference for the two "risky" decks which are associated with high reinforcement in the short term, but significant long-term debt. Interestingly, damage to VMPFC may cause both poor performance on the IGT and lack of insight concerning the acquired personality modification. Recently, our group reported a trait-related decisionmaking impairment in the three phases of bipolar disorder. In a PET study, VMPFC dysfunction was shown in bipolar manic patients impaired on a decision-making task and an association between decision-making cognition and lack of insight was described in mania. A quantitative association between grey matter volume of VMPFC and memory impairment was previously reported in schizophrenia. Research suggests that lack of insight is a prevalent feature in schizophrenia patients, like auditory hallucinations, paranoid or bizarre delusions, and disorganized speech and thinking. Because schizophrenia is associated with significant social or occupational dysfunction, previous research assessed decision-making function but indicates conflicting results. Thirteen studies have reported impaired IGT performance in patients with schizophrenia and, in seven reports, no significant differences in IGT performance between patient and healthy control groups were found. Those discrepancies may relate to multiple factors. First, most of the studies included small sample size and negative findings may be due to the large variance of net scores. Second, as suggested by Rodríguez-Sánchez et al., there is a wide disparity in performance by control subjects across studies. Third, intelligence quotient (IQ) score and level of education may be correlated with IGT performance, which may explain IGT performance differences in studies that did not control for educational or IQ score. Fourth, only two studies have systematically controlled for substance use disorder, a potential confounder. Fifth, only two studies assessed the impact of antipsychotic (AP) class on performance. Sixth, to our knowledge, no study assessed the impact of AP dosage on decision-making ability, while AP dose-reduction and dopamine increase, might lead to improvements, in cognitive functions in schizophrenia and in IGT performance in bipolar disorder, respectively. Finally, discrepancies between studies may be related to the heterogeneity of diagnostic groups. Two of the negative studies included schizophrenia and schizoaffective disorder while positive studies have generally included only patients with schizophrenia. Nevertheless, some studies that included only patients with schizophrenia failed to find differences between groups. Thus, further research should assess decision-making in schizophrenia by testing a large group of patients with homogeneity of diagnostic, in comparison with a large group of control subjects. Authors should control for IQ or level of education, substance use disorder and smoking status. While it is now accepted that DLPFC defects in schizophrenia may extend to VMPFC, future investigations should test for an association between memory, insight ability and IGT performance and assess the impact of antipsychotic dosage upon performance.

The somatic marker affecting decisional processes in obsessive-compulsive disorder

INTRODUCTION

Patients with obsessive-compulsive disorder (OCD) demonstrate impairment in decisional processes in which both cognition and emotion play a crucial role.

METHODS

We investigated the connection between decision-making performances and choice-related skin conductance responses (SCRs), to identify a somatic marker impairment affecting decisional processes in these patients. We explored SCRs during the Iowa Gambling Task in 20 OCD and 18 control, measuring anticipatory and posticipatory psychophysiological reactions according to card choices and to the outcomes of each selection.

RESULTS

Most patients exhibited weaker SCRs compared to HC, although there weren't substantial differences in magnitude between the two groups. In contrast with HC, patients with OCD showed no significant differences of SCRs activation according to card selections; they chose cards from neither favourable nor unfavourable decks.

CONCLUSIONS

The main finding of the study were the evidence of a dysfunctional biological marker in OCD subjects, affecting decision-making process. Dysfunctional patterns of SCRs could partially explain OCDs' impairment in this ability. Decision-making deficits in OCDs could be influenced in part by the lack of somatic differences in discriminating between advantageous and disadvantageous behaviour. These findings could lead to a more complete understanding of OCD.

Schizophrenia and risk-taking: impaired reward but preserved punishment processing

Risky decision-making is subserved by the frontostriatal system, which includes a network of interconnected brain regions known to be dysfunctional in patients with schizophrenia. This study aimed to investigate whether and to what extent patients with schizophrenia display a different pattern of risk-taking behavior relative to matched healthy controls. The Balloon Analogue Risk Task (BART) and the Risky-Gains Task were used as naturalistic measures of risk-taking behavior in 25 patients with schizophrenia and 25 controls. Results of the BART revealed that patients behaved more conservatively, and this in turn led to suboptimal risky decision-making. Consistently, patients behaved more conservatively in the Risky-Gains Task. Interestingly, however, they adjusted the pattern of risk-taking following a punished trial similar to controls. These findings indicate that patients have impaired reward but preserved punishment processing. This study complements previous studies on decision-making in schizophrenia and suggests specific rather than widespread abnormalities along the frontostriatal system in schizophrenia.

Cognitive decision modelling of emotion-based learning impairment in schizophrenia: the role of awareness

Individuals with schizophrenia often lack insight or awareness. Resulting impairment has been observed in various cognitive domains and, recently, linked to problems in emotion-based learning. The Iowa Gambling Task (IGT) has been used to assess emotion-based decision-making in patients with schizophrenia, but results have been inconclusive. The current study further investigates emotion-based decision-making in schizophrenia by elucidating the unique contribution of awareness. Twenty-five patients with schizophrenia and 24 healthy controls were assessed with a modified version of the IGT recording awareness at regular intervals. Symptom assessment, medication and medical history were recorded for the clinical group. Patients with schizophrenia underperformed on the IGT compared to controls. Subjective awareness levels were significantly lower in the schizophrenia group and were associated with hallucination severity. Cognitive decision modelling further indicated that patients with schizophrenia had impaired attention to losses, compared to controls. This parameter was positively correlated with awareness. We also found that positive symptoms altered awareness levels and suggest that this disruption may contribute to sub-optimal decision-making. Overall, a lack of awareness may be an important aspect in understanding impaired social cognitive functioning and emotion-based learning observed in schizophrenia.