Multidimensional measures of impulsivity in obsessive-compulsive disorder: cannot wait and stop

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.

Disentangling associations between impulsivity, compulsivity, and performance monitoring

Disorders marked by high levels of impulsivity and compulsivity have been linked to changes in performance monitoring, specifically the error-related negativity (ERN). We investigated the relationship between performance monitoring and individual differences in impulsivity and compulsivity. A total of 142 participants were recruited into four groups, each with different combinations of impulsivity and compulsivity, and they performed a flanker task to assess error-related brain activity. We defined error-related brain activity as ERN amplitude and theta power. Single-trial regression was employed to analyze the amplitude differences between incorrect and correct trials within the ERN time window. The findings revealed that impulsivity, compulsivity, and different measures of response processing exhibited distinct interactions, which were influenced by the configuration of impulsivity and compulsivity, but also depended on the measure of response processing. Specifically, high compulsivity predicted larger ERN amplitudes in individuals with low impulsivity, whereas high impulsivity had no significant effect on ERN amplitude in individuals with low compulsivity. Furthermore, when both impulsivity and compulsivity were high, no significant increase in ERN amplitude was observed; instead, there was a reduced difference between incorrect and correct trials. No significant differences were found for theta power. While the association between error-related brain activity and transdiagnostic markers or psychopathology may be smaller than generally assumed, considering the interaction between different transdiagnostic markers and their facets can enhance our understanding of the complex associations that arise during the investigation of neural correlates of performance monitoring, specifically the ERN.

Developmental deviation in delay discounting as a transdiagnostic indicator of risk for child psychopathology

BACKGROUND

The tendency to prefer smaller, immediate rewards over larger, delayed rewards is known as delay discounting (DD). Developmental deviations in DD may be key in characterizing psychiatric and neurodevelopmental disorders. Recent work empirically supported DD as a transdiagnostic process in various psychiatric disorders. Yet, there is a lack of research relating developmental changes in DD from mid-childhood to adolescence to psychiatric and neurodevelopmental disorders. Additionally, examining the interplay between socioeconomic status/total household income (THI) and psychiatric symptoms is vital for a more comprehensive understanding of pediatric pathology and its complex relationship with DD.

METHODS

The current study addresses this gap in a robust psychiatric sample of 1843 children and adolescents aged 5-18 (M = 10.6, SD = 3.17; 1,219 males, 624 females). General additive models (GAMs) characterized the shape of age-related changes in monetary and food reward discounting for nine psychiatric disorders compared with neurotypical youth (NT; n = 123). Over 40% of our sample possessed a minimum of at least three psychiatric or neurodevelopmental disorders. We used bootstrap-enhanced Louvain community detection to map DD-related comorbidity patterns. We derived five subtypes based on diagnostic categories present in our sample. DD patterns were then compared across each of the subtypes. Further, we evaluated the effect of cognitive ability, emotional and behavioral problems, and THI in relation to DD across development.

RESULTS

Higher discounting was found in six of the nine disorders we examined relative to NT. DD was consistently elevated across development for most disorders, except for depressive disorders, with age-specific DD differences compared with NTs. Community detection analyses revealed that one comorbidity subtype consisting primarily of Attention-Deficit/Hyperactivity Disorder (ADHD) Combined Presentation and anxiety disorders displayed the highest overall emotional/behavioral problems and greater DD for the food reward. An additional subtype composed mainly of ADHD, predominantly Inattentive Presentation, learning, and developmental disorders, showed the greatest DD for food and monetary rewards compared with the other subtypes. This subtype had deficits in reasoning ability, evidenced by low cognitive and academic achievement performance. For this ADHD-I and developmental disorders subtype, THI was related to DD across the age span such that participants with high THI showed no differences in DD compared with NTs. In contrast, participants with low THI showed significantly worse DD trajectories than all others. Our results also support prior work showing that DD follows nonlinear developmental patterns.

CONCLUSIONS

We demonstrate preliminary evidence for DD as a transdiagnostic marker of psychiatric and neurodevelopmental disorders in children and adolescents. Comorbidity subtypes illuminate DD heterogeneity, facilitating the identification of high-risk individuals. Importantly, our findings revealed a marked link between DD and intellectual reasoning, with children from lower-income households exhibiting lower reasoning skills and heightened DD. These observations underscore the potential consequences of compromised self-regulation in economically disadvantaged individuals with these disorders, emphasizing the need for tailored interventions and further research to support improved outcomes.

Neural correlates of risk taking in patients with obsessive-compulsive disorder during risky decision-making

BACKGROUND

The risk preference during decision-making and the neural substrates involved in patients with obsessive-compulsive disorder (OCD) remained unclear. The current study was designed to evaluate the risk-taking behaviors during decision-making and neural correlates in patients with OCD, thereby providing a deeper insight into their impaired decision-making function.

METHODS

Fifty-one patients with OCD and 50 healthy controls (HCs) were included in this study. All subjects underwent functional magnetic resonance imaging (fMRI) scans while completing the Balloon Analog Risk Task (BART). The behavior indicator and cognitive model parameter in BART, as well as the neural correlates of risk-taking behaviors were analyzed.

RESULTS

Compared to HCs, the OCD group performed a significantly higher level of risk-averse behaviors, and the cognitive model parameter revealed that patients with OCD tend to decrease their risk level after receiving negative feedbacks during BART. The fMRI results based on prespecified brain regions showed that the OCD group exhibited significantly decreased activation modulated by risk levels both in the left and right insula.

LIMITATIONS

The effect of medication in this study could not be completely ruled out, and it is difficult to temporally separate different states of decision-making in the BART.

CONCLUSIONS

Individuals with OCD exhibited a higher level of risk aversion during decision-making process, and the dysfunction of the insula may be the neural basis of the increased risk aversion in OCD. These findings provide further insights into the mechanism of risk aversion and impaired decision-making function in individuals with OCD.

Chronic Deep Brain Stimulation of the Human Nucleus Accumbens Region Disrupts the Stability of Intertemporal Preferences

When choosing between rewards that differ in temporal proximity (intertemporal choice), human preferences are typically stable, constituting a clinically relevant transdiagnostic trait. Here we show, in female and male human patients undergoing deep brain stimulation (DBS) of the anterior limb of the internal capsule/NAcc region for treatment-resistant obsessive-compulsive disorder, that long-term chronic (but not phasic) DBS disrupts intertemporal preferences. Hierarchical Bayesian modeling accounting for temporal discounting behavior across multiple time points allowed us to assess both short-term and long-term reliability of intertemporal choice. In controls, temporal discounting was highly reliable, both long-term (6 months) and short-term (1 week). In contrast, in patients undergoing DBS, short-term reliability was high, but long-term reliability (6 months) was severely disrupted. Control analyses confirmed that this effect was not because of range restriction, the presence of obsessive-compulsive disorder symptoms or group differences in choice stochasticity. Model-agnostic between- and within-subject analyses confirmed this effect. These findings provide initial evidence for long-term modulation of cognitive function via DBS and highlight a potential contribution of the human NAcc region to intertemporal preference stability over time.SIGNIFICANCE STATEMENT Choosing between rewards that differ in temporal proximity is in part a stable trait with relevance for many mental disorders, and depends on prefrontal regions and regions of the dopamine system. Here we show that chronic deep brain stimulation of the human anterior limb of the internal capsule/NAcc region for treatment-resistant obsessive-compulsive disorder disrupts the stability of intertemporal preferences. These findings show that chronic stimulation of one of the brain's central motivational hubs can disrupt preferences thought to depend on this circuit.

Behavioral domains in compulsive rats: implications for understanding compulsive spectrum disorders

Introduction

Compulsive behavior has been proposed as a transdiagnostic trait observed in different neuropsychiatric disorders, such as obsessive-compulsive disorder, autism, and schizophrenia. Research Domain Criteria (RDoC) strategy could help to disentangle the neuropsychological basis of compulsivity for developing new therapeutic and preventive approaches. In preclinical research, the selection of high-drinker (HD) vs. low-drinker (LD) animals by schedule-induced polydipsia (SIP) is considered a putative model of compulsivity, which includes a well-differentiated behavioral pattern.

Methods

The purpose of this research was to assess the cognitive control and the negative valence system domains in a phenotype of compulsive HD rats. After the selection of animals as HD or LD, we assessed behavioral inflexibility by probabilistic spatial reversal learning (PSRL), motor and cognitive impulsivity by variable delay-to-signal (VDS), and risky decision-making by rodent gambling task (rGT).

Results

HD rats performed fewer reversals and showed less probability of pressing the same lever that was previously reinforced on PSRL, more premature responses after the exposure to longer delays on VDS, and more disadvantageous risky choices on rGT. Moreover, HD animals performed more perseverative responses under the punishment period on rGT.

Discussion

These results highlight that HD compulsive phenotype exhibits behavioral inflexibility, insensitivity to positive feedback, waiting impulsivity, risky decision-making, and frustrative non-reward responsiveness. Moreover, these findings demonstrate the importance of mapping different behavioral domains to prevent, treat, and diagnose compulsive spectrum disorders correctly.

Can disorders of subjective time inform the differential diagnosis of psychiatric disorders? A transdiagnostic taxonomy of time

AIM

Time is a core aspect of psychopathology with potential for clinical use and early intervention. Temporal experience, perception, judgement and processing are distorted in various psychiatric disorders such as mood (depression and mania), anxiety, autistic, impulse-control, dissociative and attention-deficit/hyperactivity disorders. Can these disorders of time be used as early diagnostic or predictive markers? To answer this question, we develop a Transdiagnostic Taxonomy of (disordered) Time (TTT) that maps on to the symptomatological, phenomenal, perceptual and functional descriptions of each underlying disorder in a 2 × 2 × 2 state space. Temporal distortions may precede functional decline, and so assist efforts at early detection and intervention in at-risk groups.

METHOD

Firstly, this article integrates a psychological model of how time is processed with a subjective or phenomenological model of how time is experienced or perceived. Secondly, the integrated combined model of time is then used to heuristically map major psychiatric disorders on to the basic elements of temporal flow and integration.

RESULTS

The TTT systematically describes the basic temporal nature of eight diagnostic categories of psychiatric illness. It differentiates between diagnoses primarily associated with distorted "macro-level" phenomenal temporal experiences (i.e. anxiety, dissociation/PTSD, depression, and mania) from those primarily related to distorted 'micro-level' temporal processing (i.e. psychotic, impulse-control, autistic and attention-deficit/hyperactivity disorders).

CONCLUSIONS

The TTT allows differential diagnostic classification of various psychiatric disorders in terms of a possible underlying time disorder, making it useful for future diagnostic and predictive purposes using novel techniques of temporal processing, time perception, passage of time, and time perspective.

The Relationship Among Autistic Traits, Impulsivity, and Functionality in Patients With Obsessive-Compulsive Disorder

ABSTRACT

Obsessive-compulsive disorder (OCD) is a chronic mental disorder that causes disabilities. This study investigated the relationship among impulsivity, autistic traits, and disabilities in patients with OCD. We included 88 patients with OCD and 90 healthy volunteers without any mental disorders. The participants were evaluated using the Yale-Brown Obsessive-Compulsive Scale, Autism Spectrum Quotient (AQ), Barratt Impulsiveness Scale-11 (BIS-11), and World Health Organization Disability Assessment Schedule (WHODAS 2.0). Regression analyses revealed that AQ-attention switching and BIS-attentional subscale scores were associated with WHODAS-overall score in the OCD group ( p = 0.017 and p = 0.034, respectively). In the OCD group, AQ total, social skills, and communication subdomain scores partially mediated the relationship between impulsivity and disability. BIS total, attentional, and nonplanning subscale scores partially mediated the relationship between autistic traits and disability. Developing new treatment strategies for cognitive recovery, in addition to traditional treatment approaches in patients with OCD, may help increase functionality in patients with OCD.

Executive functioning in body dysmorphic disorder and obsessive-compulsive disorder

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Response Inhibition in Youth Undergoing Intensive Treatment for Obsessive Compulsive Disorder

Response Inhibition (RI) is the ability to suppress behaviors that are inappropriate for a given context. Obsessive-compulsive disorder (OCD) has been associated with impaired RI in adults as measured by the Stop Signal Task (SST). Conflicting results have been found in terms of the relationship between OCD severity and SST performance, and no studies to date have examined the relationship between SST and response to OCD treatment. Also relatively unknown is whether RI performance in OCD is associated with developmental or gender differences. This naturalistic study examined the relationship between SST performance, OCD severity, and OCD treatment response in a pediatric sample undergoing intensive treatment involving exposure and response prevention and medication management (n = 36). The SST and Children's Yale-Brown Obsessive Compulsive Scale (CYBOCS) were administered at admission and program discharge. OCD severity was not significantly related to stop signal reaction time (SSRT) in the whole sample and among subgroups divided by age and gender. Baseline SSRT and SSRT change did not predict CYBOCS change across treatment in the whole sample, but exploratory analyses indicated both were significant predictors among female adolescents. Results suggest there may be developmental gender differences in the relationship between RI and clinical improvement in pediatric OCD.

Abnormal Responses in Cognitive Impulsivity Circuits Are Associated with Glycosylated Hemoglobin Trajectories in Type 1 Diabetes Mellitus and Impaired Metabolic Control

BACKGROUND

Risky health decisions and impulse control profiles may impact on metabolic control in type 1 diabetes mellitus (T1DM). We hypothesize that the neural correlates of cognitive impulsivity and decision-making in T1DM relate to metabolic control trajectories.

METHODS

We combined functional magnetic resonance imaging (fMRI), measures of metabolic trajectories (glycosylated hemoglobin [HbA1c] over multiple time points) and behavioral assessment using a cognitive impulsivity paradigm, the Balloon Analogue Risk Task (BART), in 50 participants (25 T1DM and 25 controls).

RESULTS

Behavioral results showed that T1DM participants followed a rigid conservative risk strategy along the iterative game. Imaging group comparisons showed that patients showed larger activation of reward related, limbic regions (nucleus accumbens, amygdala) and insula (interoceptive saliency network) in initial game stages. Upon game completion differences emerged in relation to error monitoring (anterior cingulate cortex [ACC]) and inhibitory control (inferior frontal gyrus). Importantly, activity in the saliency network (ACC and insula), which monitors interoceptive states, was related with metabolic trajectories, which was also found for limbic/reward networks. Parietal and posterior cingulate regions activated both in controls and patients with adaptive decision-making, and positively associated with metabolic trajectories.

CONCLUSION

We found triple converging evidence when comparing metabolic trajectories, patients versus controls or risk averse (non-learners) versus patients who learned by trial and error. Dopaminergic reward and saliency (interoceptive and error monitoring) circuits show a tight link with impaired metabolic trajectories and cognitive impulsivity in T1DM. Activity in parietal and posterior cingulate are associated with adaptive trajectories. This link between reward-saliency-inhibition circuits suggests novel strategies for patient management.

A comparison of phenomenological, clinical and familial psychiatric features of pediatric OCD and trichotillomania

OBJECTIVES

Although trichotillomania (TTM) is classified in the obsessive-compulsive disorders (OCD) chapter of the DSM-5, several studies showed that it has several differences. The aim of this study was to examine the phenomenology, comorbidity, and family psychiatric characteristisc of childhood TTM and OCD.

METHODS

This study compared youth ages 6-17 years with a primary diagnosis of TTM (n = 63) to those with primary OCD (n = 65) on clinical and familial psychiatric characteristics.

RESULTS

In our study, the findings showed that family history of schizophrenia (42.3%) was higher among patients with TTM than the OCD group, while the history of OCD (55.8%) in the family was significantly higher among the OCD group (p < 0.001). The behaviour of plucking eyebrows was significantly higher among patients with TTM comorbid OCD than patients with only trichotillomania. TTM patients with comorbid OCD had one-dimensional symptom distribution than the presence of the OCD-only group, and the severity of OCD was lower. The incidence of pathological doubting was higher among the TTM group with comorbid OCD, than those with only OCD diagnosis.

CONCLUSIONS

These findings support significant differences between OCD and TTM. Differences between OCD and TTM may reflect differences in underlying psychobiology, and may necessitate contrasting treatment approaches.KEYPOINTSWe aimed to compare the trichotillomania in itself and in the presence of OCD with the OCD group.Even if OCD accompanied trichotillomania, OCD symptom dimensions and severity were found to be lower than in the OCD-only group.Trichotillomania is a heterogeneous disorder with different dimensions besides the OCD spectrum.

Using event-related potentials to characterize inhibitory control and self-monitoring across impulsive and compulsive phenotypes: a dimensional approach to OCD

OBJECTIVE

"Subsyndromal" obsessive-compulsive disorder symptoms (OCDSs) are common and cause impaired psychosocial functioning. OCDSs are better captured by dimensional models of psychopathology, as opposed to categorical diagnoses. However, such dimensional approaches require a deep understanding of the underlying neurocognitive drivers and impulsive and compulsive traits (ie, neurocognitive phenotypes) across symptoms. This study investigated inhibitory control and self-monitoring across impulsivity, compulsivity, and their interaction in individuals (n = 40) experiencing mild-moderate OCDSs.

METHODS

EEG recording concurrent with the stop-signal task was used to elicit event-related potentials (ERPs) indexing inhibitory control (ie, N2 and P3) and self-monitoring (ie, error-related negativity and correct-related negativity (CRN): negativity following erroneous or correct responses, respectively).

RESULTS

During unsuccessful stopping, individuals high in both impulsivity and compulsivity displayed enhanced N2 amplitude, indicative of conflict between the urge to respond and need to stop (F(3, 33) = 1.48, P < .05, 95% Cl [-0.01, 0.001]). Individuals high in compulsivity and low in impulsivity showed reduced P3 amplitude, consistent with impairments in monitoring failed inhibitory control (F(3, 24) = 2.033, P < .05, 95% CI [-0.002, 0.045]). Following successful stopping, high compulsivity (independent of impulsivity) was associated with lower CRN amplitude, reflecting hypo-monitoring of correct responses (F(4, 32) = 4.76, P < .05, 95% CI [0.01, 0.02]), and with greater OCDS severity (F(3, 36) = 3.32, P < .05, 95% CI [0.03, 0.19]).

CONCLUSION

The current findings provide evidence for differential, ERP-indexed inhibitory control and self-monitoring profiles across impulsive and compulsive phenotypes in OCDSs.

Risking Everything in Obsessive-Compulsive Disorder: An Analogue Decision-Making Study

An experiment examined decision-making processes among nonclinical participants with low or high levels of OCD symptomatology (N = 303). To better simulate the decision environments that are most likely to be problematic for clients with OCD, we employed decision tasks that incorporated "black swan" options that have a very low probability but involve substantial loss. When faced with a choice between a safer option that involved no risk of loss or a riskier alternative with a very low probability of substantial loss, most participants chose the safer option regardless of OCD symptom level. However, when faced with choices between options that had similar expected values to the previous choices, but where each option had some low risk of a substantial loss, there was a significant shift towards riskier decisions. These effects were stronger when the task involved a contamination based, health-relevant decision task as compared to one with financial outcomes. The results suggest that both low and high symptom OC participants approach decisions involving risk-free options and decisions involving risky alternatives in qualitatively different ways. There was some evidence that measures of impulsivity were better predictors of the shift to risky decision making than OCD symptomatology.

Frozen in (e)motion: How reactive motor inhibition is influenced by the emotional content of stimuli in healthy and psychiatric populations

Efficient inhibitory control is vital. However, environmental cues can influence motor control especially in an emotional context. One common task to measure inhibitory control is the stop-signal task (SST), which asks participants to respond to go stimuli knowing that on some trials a stop signal will be presented, requiring them to inhibit their response. This paradigm estimates the ability to inhibit already-initiated responses by calculating participants' stop-signal reaction times (SSRT), an index of inhibitory control. Here, we aim to review the existing, often contradictory, evidence on the influence of emotional stimuli on the inhibitory process. We aim to discuss which factors may reveal an interference as well as an advantage of emotional stimuli on action inhibition performance. Finally, we review the existing evidence that has investigated the effect of such stimuli on action inhibition in the psychiatric population. Important factors are the relevance, the intensity and the valence of the emotional stimulus, as well as the affected component of the motor control. From all this evidence, it is clear that understand precisely how emotion is integrated into core executive functions, such as inhibitory control, is essential not only for cognitive neuroscience, but also for refining neurocognitive models of psychopathology.

Comparing impulsivity in borderline personality, schizophrenia and obsessional-compulsive disorders: Who is ahead?

OBJECTIVE

Impulsivity impacts life domains and in a psychiatric context is often associated with disorders severity and stigmatization. Borderline personality disorder's (BPD), Schizophrenic disorder's (SZD), and obsessional compulsive disorder's (OCD) impulsivity issues relate to worse prognosis. This study aims to compare these disorders assessing their proneness to impulsivity and urgency.

METHODS

We recruited 90 patients among them OCD (n = 25), SZD (n = 23), and BPD (n = 50), and 24 healthy control participants (HC). We assessed the diagnosis according and measured the impulsivity level.

RESULTS

Our results showed that BPD was significantly more impulsive than HC, SZD, and OCD. HC, SZD, and OCD being equivalent on their global Urgency-Premeditation-Perseverance-Sensation seeking scores. For urgency, BPD was also superior to others, OCD was superior to HC, but SZD and HC were equivalent. The urgency was correlated to SZD's scale for SZD, no link appeared between borderline personality questionnaire and Yale-Brown Obsessive-Compulsive Scale's score.

CONCLUSION

These results question the existent literature relating impulsivity and SZD.

Shared and unique neural mechanisms underlying pediatric trichotillomania and obsessive compulsive disorder

BACKGROUND

Little is known about the neural underpinnings of pediatric trichotillomania (TTM). We examined error-related negativity (ERN)-amplitude and theta-EEG power differences among youth with TTM, OCD, and healthy controls (HC).

METHODS

Forty channel EEG was recorded from 63 pediatric participants (22 with TTM, 22 with OCD, and 19 HC) during the Eriksen Flanker Task. EEG data from inhibitory control were used to derive estimates of ERN amplitude and event-related spectral power associated with motor inhibition.

RESULTS

TTM and HC were similar in brain activity patterns in frontal and central regions and TTM and OCD were similar in the parietal region. Frontal ERN-amplitude was significantly larger in OCD relative to TTM and HC, who did not differ from each other. The TTM group had higher theta power compared to OCD in frontal and central regions, and higher theta than both comparison groups in right motor cortex and superior parietal regions. Within TTM, flanker task performance was correlated with EEG activity in frontal, central, and motor cortices whereas global functioning and impairment were associated with EEG power in bilateral motor and parietal cortices.

CONCLUSIONS

Findings are discussed in terms of shared and unique neural mechanisms in TTM and OCD and treatment implications.

Multifaceted impulsivity in obsessive-compulsive disorder with hoarding symptoms

OBJECTIVE

Hoarding is common in obsessive-compulsive disorder (OCD), and OCD with hoarding may have poorer prognostic features than OCD without hoarding. The aim of this study was to investigate the relationship between multifaceted impulsivity and hoarding symptoms in individuals with OCD. This relationship is important to be able to understand the psychopathological mechanisms of hoarding symptoms in OCD patients.

METHODS

The study included 136 individuals with OCD classified as OCD with high hoarding symptoms (OCDwHH, n = 41) and OCD with low/none hoarding symptoms (OCDwLH, n = 95), together with 94 healthy control subjects. All the participants completed the Hoarding Rating Scale-Interview, Barratt Impulsiveness Scale-11, Yale-Brown Obsessions and Compulsions Scale, Hamilton Depression Rating Scale, and Hamilton Anxiety Rating Scale.

RESULTS

The OCDwHH group had more severe anxiety (p = 0.016) and attentional impulsivity (p = 0.002) than OCDwLH. Attentional impulsivity scores were positively correlated with hoarding symptom scores (p < 0.001). Both attentional and motor impulsivity scores were positively correlated with anxiety levels (p = 0.037, p = 0.045, respectively). In partial correlation analysis, motor impulsivity was positively correlated with the severity of hoarding symptoms controlling for anxiety severity (p = 0.045). In hierarchical linear regression analysis, only attentional impulsivity predicted the severity of hoarding symptoms independently of anxiety, severity of obsessive-compulsive symptoms and motor impulsivity (β = 0.268, Adjusted R2 = 0.114, p = 0.006).

CONCLUSION

Attentional impulsivity is associated with hoarding symptoms in OCD. Future studies that reveal this relationship may contribute to treatment modalities for the OCD patients with hoarding symptoms.

Neuropsychological Research in Obsessive-Compulsive Disorder: Current Status and Future Directions

Neuropsychological functions in obsessive-compulsive disorder (OCD) have been extensively investigated. Despite some common findings across studies indicating deficient test performance across cognitive domains with small to medium effect sizes, results remain inconsistent and heterogeneous. However, multiple past attempts to identify moderators that may account for such variability have been unrewarding. Typical moderators including symptom severity, age at onset, medication status, and comorbid conditions failed to provide sufficient explanatory power. It has then been posited that these inconsistencies may be attributed to the inherent heterogeneous nature of the disorder (i.e., symptom dimensions), or to the natural fluctuation in symptom severity. However, recent meta-analyses suggest that these factors may not account for the persistent unexplained variability. Other potential factors-some of which are unique to neuropsychological testing-received scarce research attention, including definition of cognitive impairments, specificity and selection of test and outcome measures, and their limited ecological validity. Other moderators, particularly motivational aspects, and metacognitive factors (e.g., self-efficacy) were not previously addressed despite their potential association to OCD, and their documented impact on cognitive function. The aim of the present mini-review is to provide an updated succinct overview of the current status of the neuropsychological literature in OCD and expanding upon oft-neglected potential moderators and their putative impact on neuropsychological findings in OCD. Our goal is to highlight important avenues for further research and provide a road map for investigators in order to advance our understanding of cognitive functions in OCD that has been stagnant in the past decade.

Neurocognitive Endophenotypes of OCD

In this chapter, I address the concept of endophenotypes for obsessive-compulsive disorder (OCD). Endophenotypes are objective and heritable quantitative traits hypothesized to be more biologically tractable than distal clinical phenotypes. This approach has been adopted to gain a better understanding of psychiatric conditions in general. It is theorized that endophenotypes will particularly assist in clarifying both the diagnostic status and aetiological origins of complex neuropsychiatric conditions such as OCD. At the cognitive level, separable constructs of relevance for OCD have been identified. The prevailing model for OCD assumes the development of abnormalities within fronto-striatal neural circuits leading to impairment of executive functions and their neuropsychological subcomponents. Here, I address whether this model can guide towards the identification of endophenotypes for this condition and discuss possible implications.

Impulsivity, hostility and suicidality in patients diagnosed with obsessive compulsive disorder

Background: There are limited data on suicidal behaviour in obsessive-compulsive disorder (OCD). This study aimed to evaluate several aspects affecting suicidality in OCD patients and determine whether impulsivity or hostility are associated with suicide attempts in this vulnerable group.Methods: Eighty-one patients with OCD were assessed by structured clinical interview for DSM-IV (SCID I), Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), Suicide Probability Scale (SPS), Barratt impulsivity scale-11 (BIS) and Scale for suicide ideation (SSI).Results: Of the 81 patients, 22 (27%) had suicide ideation, 29 (33%) attempted suicides with OCD and 30 (37%) OCD patients who never experienced suicide ideation nor attempted suicide. Suicide ideation was associated with high hopelessness, higher severity of OCD and the presence of aggressive obsessions. On the other hand, suicide attempts were associated with longer duration of untreated illness, cognitive impulsivity, higher severity of OCD symptoms and the presence of religious obsessions.Conclusion: Higher severity of OCD symptoms is associated with both suicide ideation and attempts. And while hopelessness was related to suicidal thoughts, cognitive impulsivity may have acted as a facilitating factor for suicide attempts. Higher frequency of symptoms like religious/ aggressive obsessions was also associated with suicidality. It is vital that patients with OCD undergo detailed assessment for suicide risk.Key pointsOCD is associated with a high risk for suicidal behaviour.Suicide ideation was associated with high levels of hopelessness, OCD severity, and the presence of aggressive obsessions.Suicide attempts were associated with longer duration of untreated illness, cognitive impulsivity, severity of OCD, and the presence of religious obsessions.

Reward-related attentional capture and cognitive inflexibility interact to determine greater severity of compulsivity-related problems

BACKGROUND AND OBJECTIVES

Neurocognitive processes are key drivers of addictive and compulsive disorders. The current study examined whether reward-related attentional capture and cognitive inflexibility are associated with impulsive and/or compulsive personality traits, and whether these cognitive characteristics interact to predict greater compulsivity-related problems across obsessive-compulsive and drinking behaviors.

METHODS

One-hundred and seventy-three participants (mean age = 34.5 years, S.D = 8.4, 42% female) completed an online visual search task to measure reward-related attentional capture and its persistence following reversal of stimulus-reward contingencies. Participants also completed questionnaires to assess trait impulsivity, compulsivity, alcohol use, and obsessive-compulsive behaviors.

RESULTS

Greater reward-related attentional capture was associated with trait compulsivity, over and above all impulsivity dimensions, while greater cognitive inflexibility was associated with higher negative urgency (distress-elicited impulsivity). Reward-related attentional capture and cognitive inflexibility interacted to predict greater compulsivity-related problems among participants who reported obsessive-compulsive behaviors in the past month (n = 57) as well as current drinkers (n = 88). Follow-up analyses showed that, for OCD behaviors, this interaction was driven by an association between higher reward-related attentional capture and more problematic behaviors among cognitively inflexible participants only. For drinking, the same pattern was seen, albeit at trend level.

LIMITATIONS

This study includes a non-clinical, online sample and is cross-sectional, thus its findings need to be interpreted with these limitations in mind.

CONCLUSIONS

Reward-related attentional capture and cognitive flexibility are related to trait compulsivity and impulsivity (negative urgency) respectively, and interact to determine more problematic behaviors.

A critical inquiry into marble-burying as a preclinical screening paradigm of relevance for anxiety and obsessive-compulsive disorder: Mapping the way forward

Rodent marble-burying behavior in the marble-burying test (MBT) is employed as a model or measure to study anxiety- and compulsive-like behaviors or anxiolytic and anticompulsive drug action. However, the test responds variably to a range of pharmacological interventions, and little consensus exists regarding specific methodologies for its execution. Regardless, the test is widely applied to investigate the effects of pharmacological, genetic, and behavioral manipulations on purported behaviors related to the said neuropsychiatric constructs. Therefore, in the present review we attempt to expound the collective translational significance of the MBT. We do this by (1) reviewing burying behavior as a natural behavioral phenotype, (2) highlighting key aspects of anxiety and obsessive-compulsive disorder from a translational perspective, (3) reviewing the history and proof of concept of the MBT, (4) critically appraising potential methodological confounds in execution of the MBT, and (5) dissecting responses of the MBT to various pharmacological interventions. We conclude by underlining that the collective translational value of the MBT will be strengthened by contextually valid experimental designs and objective reporting of data.

Avoid jumping to conclusions under uncertainty in Obsessive Compulsive Disorder

High levels of intolerance of uncertainty (IU) could contribute to abnormal decision making in uncertain situations. Patients with Obsessive Compulsive Disorder (OCD) often report high IU, indecisiveness and the need to seek greater certainty before making decisions. The Beads task is a commonly used task assessing the degree of information gathering prior to making a decision and so would be predicted to show impairments in OCD patients. Results to date have found mixed support for this, possibility due to methodological issues. Here, a group of OCD patients (n = 50) with no comorbidities was compared with age, gender, and verbal-IQ matched controls (n = 50) on the most commonly used version of the Beads task. An independent sample of healthy volunteers with high versus low OC symptoms, and high versus low IU were also assessed (n = 125). There was no evidence that patients with OCD differed from control volunteers in the degree of information gathering prior to making a decision. Medication status and age did not appear to mediate performance. Similarly, there were no association in healthy volunteers between task performance and OC or IU characteristics. Additional measures examining the degree of certainty initially showed support for greater uncertainty in patients, but this was due to deviations from task instructions in a subset of patients. We conclude that despite the large sample size and good matching between groups, the Beads task in its most widely used form is not a useful measure of IU or of information gathering in OCD. The results argue against a robust behavioural difference in OCD when compared to controls. Recommendations for future studies employing the task are discussed.

Effect of Schedule-Induced Behavior on Responses of Spontaneously Hypertensive and Wistar-Kyoto Rats in a Delay-Discounting Task: A Preliminary Report

Delay discounting is the loss of the subjective value of an outcome as the time to its delivery increases. It has been suggested that organisms can become more tolerant of this delay when engaging in schedule-induced behaviors. Schedule-induced behaviors are those that develop at a high rate during intermittent reinforcement schedules without the need of arranged contingency to the reinforcer, and they have been considered as a model of compulsivity. There is evidence that relates compulsivity to greater delay discounting. The rate of delay discounting represents how impulsive the subject is, as the rate of discounting increases the higher the impulsivity. Thus, the main purpose of this study was to undertake a preliminary evaluation of whether developing schedule-induced behaviors affects performance in a delay-discounting task, by comparing spontaneously hypertensive rats (SHRs) and Wistar-Kyoto (WKY) rats. The rats were exposed to a task that consisted of presenting the subjects with two levers: one produced a small, immediate food reinforcer while the other one produced a larger, delayed reinforcer. During Condition A, the levers were presented, and a water bottle and a running wheel were available in the conditioning chambers; during Condition B, only the levers were presented. SHR and WKY rats developed schedule-induced behaviors during Condition A and showed no difference in discounting rates, contradicting previous reports. Lick allocation during response-reinforcer delays and the inter-trial interval (ITI) showed, respectively, pre- and post-food distributions. Discounting rates during Condition B (when rats could not engage in schedule-induced behaviors) did not reach statistical significance difference among strains of animals, although it was observed a tendency for WKY to behave more self-controlled. Likewise it was not found any effect of schedule-induced behavior on discounting rates, however, a tendency for WKY rats to behave more impulsive during access to drink and run seems to tentatively support the idea of schedule-induced behavior as a model of compulsivity in those rats, being impulsivity simply defined as an excess in behavior.

Delay Discounting as a Transdiagnostic Process in Psychiatric Disorders: A Meta-analysis

IMPORTANCE

Delay discounting is a behavioral economic index of impulsive preferences for smaller-immediate or larger-delayed rewards that is argued to be a transdiagnostic process across health conditions. Studies suggest some psychiatric disorders are associated with differences in discounting compared with controls, but null findings have also been reported.

OBJECTIVE

To conduct a meta-analysis of the published literature on delay discounting in people with psychiatric disorders.

DATA SOURCES

PubMed, MEDLINE, PsycInfo, Embase, and Web of Science databases were searched through December 10, 2018. The psychiatric keywords used were based on DSM-IV or DSM-5 diagnostic categories. Collected data were analyzed from December 10, 2018, through June 1, 2019.

STUDY SELECTION

Following a preregistered Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) protocol, 2 independent raters reviewed titles, abstracts, and full-text articles. English-language articles comparing monetary delay discounting between participants with psychiatric disorders and controls were included.

DATA EXTRACTION AND SYNTHESIS

Hedges g effect sizes were computed and random-effects models were used for all analyses. Heterogeneity statistics, one-study-removed analyses, and publication bias indices were also examined.

MAIN OUTCOMES AND MEASURES

Categorical comparisons of delay discounting between a psychiatric group and a control group.

RESULTS

The sample included 57 effect sizes from 43 studies across 8 diagnostic categories. Significantly steeper discounting for individuals with a psychiatric disorder compared with controls was observed for major depressive disorder (Hedges g = 0.37; P = .002; k = 7), schizophrenia (Hedges g = 0.46; P = .004; k = 12), borderline personality disorder (Hedges g = 0.60; P < .001; k = 8), bipolar disorder (Hedges g = 0.68; P < .001; k = 4), bulimia nervosa (Hedges g = 0.41; P = .001; k = 4), and binge-eating disorder (Hedges g = 0.34; P = .001; k = 7). In contrast, anorexia nervosa exhibited statistically significantly shallower discounting (Hedges g = -0.30; P < .001; k = 10). Modest evidence of publication bias was indicated by a statistically significant Egger test for schizophrenia and at the aggregate level across studies.

CONCLUSIONS AND RELEVANCE

Results of this study appear to provide empirical support for delay discounting as a transdiagnostic process across most of the psychiatric disorders examined; the literature search also revealed limited studies in some disorders, notably posttraumatic stress disorder, which is a priority area for research.

Obsessive-Compulsive Symptoms Are Associated With Increased Delay Discounting in a Novel Hand-Washing Task

Delay discounting is a theoretical framework for assessing impulsivity characterized by a tendency to choose SSRs over LLRs. Despite the potential therapeutic value of targeting impulsive choice in the context of obsessive-compulsive (OC) symptoms, little research has been done to examine the link between the 2. In the present study, we examined the role of impulsivity in OC symptoms using a monetary and novel hand-washing delay-discounting task. Participants completed both delay-discounting procedures, as well as the Obsessive-Compulsive Inventory-Revised (OCI-R; Foa et al.,2002). Participants who showed steeper delay discounting in the monetary discounting task also tended to discount steeply in the washing task. In addition, participants showed significantly more delay discounting in the washing than in the monetary task, suggesting contextual control over impulsive behavior. Further, participants with washing compulsions demonstrated greater delay discounting on the washing task than those without washing compulsions. Higher scores on the Washing subscale of the OCI-R uniquely predicted delay discounting in the washing task at a level of marginal significance. Our findings suggest that impulsivity may be implicated in OC symptoms, and indicate the need for a more precise conceptualization of the relationship between impulsivity and compulsivity.

Association of Affected Neurocircuitry With Deficit of Response Inhibition and Delayed Gratification in Attention Deficit Hyperactivity Disorder: A Narrative Review

The neural networks that constitute corticostriatothalamocortical circuits between prefrontal cortex and subcortical structure provide a heuristic framework for bridging gaps between neurocircuitry and executive dysfunction in attention deficit hyperactivity disorder (ADHD). “Cool” and “Hot” executive functional theory and the models of dual pathway are supposed to be applied within the neuropsychology of ADHD. The theoretical model elaborated response inhibition and delayed gratification in ADHD. We aimed to review and summarize the literature about the circuits on ADHD and ADHD-related comorbidities, as well as the effects of neurocircuitry on the executive dysfunction in ADHD.

Archetypes of human cognition defined by time preference for reward and their brain correlates: An evolutionary trade-off approach

Biological systems carry out multiple tasks in their lifetime, which, in the course of evolution, may lead to trade-offs. In fact phenotypes (different species, individuals within a species, circuits, bacteria, proteins, etc.) cannot be optimal at all tasks, and, according to Pareto optimality theory, lay into a well-defined geometrical distribution (polygons and/or polyhedrons) in the space of traits. The vertices of this distribution contain archetypes, namely phenotypes that are specialists at one of the tasks, whereas phenotypes toward the center of the geometrical distribution show average performance across tasks. We applied this theory to the variability of cognitive and behavioral scores measured in 1206 individuals from the Human Connectome Project. Among all possible combinations of pairs of traits, we found the best fit to Pareto optimality when individuals were plotted in the trait-space of time preferences for reward, evaluated with the Delay Discounting Task (DDT). The DDT measures subjects' preference in choosing either immediate smaller rewards or delayed larger rewards. Time preference for reward was described by a triangular distribution in which each of the three vertices included individuals who used a particular strategy to discount reward. These archetypes accounted for variability on many cognitive, personality, and socioeconomic status variables, as well as differences in brain structure and functional connectivity, with only a weak influence of genetics. In summary, time preference for reward reflects a core variable that biases human phenotypes via natural and cultural selection.

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

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

Evaluating Proactive Strategy in Patients With OCD During Stop Signal Task

OBJECTIVES

The aim of the present study was to investigate "Proactive-Adjustment hypothesis" (PA) during the Stop Signal Task (SST). The PA is implied in the highly inconsistent literature, and it deals with the role of response inhibition (RI) in obsessive-compulsive disorder (OCD). This hypothesis assumed that participants would balance stopping and going by adjusting the response threshold (RT) in the go task. We verified whether the PA strategy was also implemented in our clinical group.

METHODS

To reach this goal, we analyzed SST performances in a group of 36 patients with OCD and 36 healthy controls (HCs). To identify different participants' behaviors during the task, without preconceived notions regarding the diagnosis, we performed a cluster analysis. Furthermore, we analyzed the influence of drug therapy and we investigated whether the rule and reversal acquisition investigated with the Intra-Extra Dimensional Set Shift, differed in the two clusters.

RESULTS

We did not find any difference relative to the number of patients with OCD and HCs included in the two clusters. Furthermore, we found that only Not Proactive participants performed the task as fast as possible, while Proactive participants consistently slowed down their RTs and showed a lower number of Direction Errors, higher Stop Signal Delay, and worse cognitive flexibility.

CONCLUSIONS

Our results show that among patients with OCD the use of PA is changeable and does not differ from HCs. This finding supports the idea that the RI heterogeneity concerning patients with OCD could be related to PA. (JINS, 2018, 24, 703-714).

Planning functioning and impulsiveness in obsessive-compulsive disorder

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

Cool and Hot Aspects of Executive Function in Childhood Obsessive-Compulsive Disorder

Aspects of executive functioning (EF) have been put forward as endophenotypes in obsessive- compulsive disorder (OCD) and meta-analyses support EF underperformance in adult samples. Childhood-onset OCD has been suggested to constitute a separate neurodevelopmental subtype of the disorder but studies on neuropsychological functioning in childhood OCD are limited. The aim of the present study was to investigate performance-based EF in pediatric OCD using observed and latent variable analyses. A case-control design was applied including 50 unmedicated children and adolescents with OCD aged 7-17 years of which 70% were female, 50 pairwise age and gender matched non-psychiatric controls (NP) and 38 children and adolescents with mixed anxiety disorders (MA). Participants underwent structured diagnostic interviews and assessment with a battery encompassing cool EF tasks of working memory, set shifting, inhibition, and planning, and hot EF tasks of decision making and dot probe paradigm affective interference. First, groups were compared on observed variables with multilevel mixed-effects linear regression and analysis of variance. Then the latent structure of cool EF was tested with confirmatory factor analysis (CFA) and groups were compared on the CFA scores. No significant differences between groups appeared on individual cool EF tasks. On the hot EF tasks the OCD group displayed significant interference effects on the dot probe paradigm OCD-specific stimuli relative to NP, but not compared to MA and no group differences emerged for decision making. In the CFA a one-factor solution showed best fit, but the groups did not differ significantly on the resulting latent variable. The present study does not support cool or hot EF impairments in childhood OCD.

Relationship of Probable Attention Deficit Hyperactivity Disorder with Severity of Psychopathology and Impulsivity in a Sample of Male Patients with Opioid Use Disorder

OBJECTIVE

The aim of the present study was to evaluate relationship of probable attention deficit hyperactivity disorder (ADHD) with severity of psychopathology and the effect of impulsivity on this relationship in a sample of male patients with opioid use disorder (OUD).

METHODS

Participants included 234 patients (115 inpatients and 119 outpatients) with OUD. Participants were evaluated with the Adult ADHD Self-Report Scale (ASRS-v1.1), the Symptom Checklist-90-R (SCL-90-R) and the Short Form of Barratt Impulsiveness Scale (BIS-11-SF).

RESULTS

Psychopathology and impulsivity scores were higher among those with the probable ADHD. ADHD scores were midly to moderately correlated with impulsivity and psychopathology scores. In logistic regression analyses, while severity of general psychopathology and impulsivity predicted probable ADHD in the first Model, in the second Model, among dimensions of psychopathology obsessive compulsive (OC) dimension, whereas among dimensions of impulsivity non-planning and motor impulsivity predicted probable ADHD.

CONCLUSION

These findings suggest that probable ADHD is related with the severity of psychopathology, particularly OC dimension, while the severity of impulsivity may have an partial mediator (particularly non-planning and motor impulsivity) effect on this relationship among patients with OUD.

Unpacking the role of self-reported compulsivity and impulsivity in obsessive-compulsive disorder

OBJECTIVE

We aimed to determine whether individuals with obsessive-compulsive disorder (OCD) and demographically matched healthy individuals can be clustered into distinct clinical subtypes based on dimensional measures of their self-reported compulsivity (OBQ-44 and IUS-12) and impulsivity (UPPS-P).

METHODS

Participants (n=217) were 103 patients with a clinical diagnosis of OCD; 79 individuals from the community who were "OCD-likely" according to self-report (Obsessive-Compulsive Inventory-Revised scores equal or greater than 21); and 35 healthy controls. All data were collected between 2013 and 2015 using self-report measures that assessed different aspects of compulsivity and impulsivity. Principal component analysis revealed two components broadly representing an individual's level of compulsivity and impulsivity. Unsupervised clustering grouped participants into four subgroups, each representing one part of an orthogonal compulsive-impulsive phenotype.

RESULTS

Clustering converged to yield four subgroups: one group low on both compulsivity and impulsivity, comprised mostly of healthy controls and demonstrating the lowest OCD symptom severity; two groups showing roughly equal clinical severity, but with opposing drivers (i.e., high compulsivity and low impulsivity, and vice versa); and a final group high on both compulsivity and impulsivity and recording the highest clinical severity. Notably, the largest cluster of individuals with OCD was characterized by high impulsivity and low compulsivity. Our results suggest that both impulsivity and compulsivity mediate obsessive-compulsive symptomatology.

CONCLUSIONS

Individuals with OCD can be clustered into distinct subtypes based on measures of compulsivity and impulsivity, with the latter being found to be one of the more defining characteristics of the disorder. These dimensions may serve as viable and novel treatment targets.

Response inhibition and error-monitoring processes in individuals with obsessive-compulsive disorder

Response inhibition (RI) has been putatively linked to the symptoms of OCD. Despite the enticing link between RI and OCD, there are points in the relationship that require clarification. We examined the RI-OCD relationship taking into account a) the potentially differential pattern of RI-OCD relationship between obsessions and compulsions, and b) the potentially confounding effect of negative affect, particularly in regards to depression. Additionally, we investigated how error-monitoring processes in the inhibitory context account for OCD symptoms. Results showed that the RI-OCD relationship is robust in regards to compulsion symptoms, but not for obsessions, even when controlling for negative affect. Additionally, while individuals with OCD display behavioral slow-down following commission errors on the stop-signal task, slow-down following successful inhibition is significantly related to compulsion symptoms. Findings suggest that future studies investigating RI in OCD should take into account heterogeneous clinical presentations in OCD, as well as incorporate error-monitoring variables to better understand RI processes in OCD.

Value-based decision making under uncertainty in hoarding and obsessive- compulsive disorders

Difficulties in decision making are a core impairment in a range of disease states. For instance, both obsessive- compulsive disorder (OCD) and hoarding disorder (HD) are associated with indecisiveness, inefficient planning, and enhanced uncertainty intolerance, even in contexts unrelated to their core symptomology. We examined decision-making patterns in 19 individuals with OCD, 19 individuals with HD, 19 individuals with comorbid OCD and HD, and 57 individuals from the general population, using a well-validated choice task grounded in behavioral economic theory. Our results suggest that difficulties in decision making in individuals with OCD (with or without comorbid HD) are linked to reduced fidelity of value-based decision making (i.e. increase in inconsistent choices). In contrast, we find that performance of individuals with HD on our laboratory task is largely intact. Overall, these results support our hypothesis that decision-making impairments in OCD and HD, which can appear quite similar clinically, have importantly different underpinnings. Systematic investigation of different aspects of decision making, under varying conditions, may shed new light on commonalities between and distinctions among clinical syndromes.

Neural dysfunction during temporal discounting in paediatric Attention-Deficit/Hyperactivity Disorder and Obsessive-Compulsive Disorder

Both Attention-Deficit/Hyperactivity Disorder (ADHD) and Obsessive-Compulsive Disorder (OCD) are associated with choice impulsivity, i.e. the tendency to prefer smaller immediate rewards over larger delayed rewards. However, the extent to which this impulsivity is mediated by shared or distinct underlying neural mechanisms is unclear. Twenty-six boys with ADHD, 20 boys with OCD and 20 matched controls (aged 12-18) completed an fMRI version of an individually adjusted temporal discounting (TD) task which requires choosing between a variable amount of money now or £100 in one week, one month or one year. Activations to immediate and delayed reward choices were compared between groups using a three-way ANCOVA. ADHD patients had steeper discounting rates on the task relative to controls. OCD patients did not differ from controls or patients with ADHD. Patients with ADHD and OCD showed predominantly shared activation deficits during TD in fronto-striato-insular-cerebellar regions responsible for self-control and temporal foresight, suggesting that choice impulsivity is mediated by overlapping neural dysfunctions in both disorders. OCD patients alone showed dysfunction relative to controls in right orbitofrontal and rostrolateral prefrontal cortex, extending previous findings of abnormalities in these regions in OCD to the domain of choice impulsiveness.

Comparison of neural substrates of temporal discounting between youth with autism spectrum disorder and with obsessive-compulsive disorder

BACKGROUND

Autism spectrum disorder (ASD) and obsessive-compulsive disorder (OCD) share abnormalities in hot executive functions such as reward-based decision-making, as measured in the temporal discounting task (TD). No studies, however, have directly compared these disorders to investigate common/distinct neural profiles underlying such abnormalities. We wanted to test whether reward-based decision-making is a shared transdiagnostic feature of both disorders with similar neurofunctional substrates or whether it is a shared phenotype with disorder-differential neurofunctional underpinnings.

METHODS

Age and IQ-matched boys with ASD (N = 20), with OCD (N = 20) and 20 healthy controls, performed an individually-adjusted functional magnetic resonance imaging (fMRI) TD task. Brain activation and performance were compared between groups.

RESULTS

Boys with ASD showed greater choice-impulsivity than OCD and control boys. Whole-brain between-group comparison revealed shared reductions in ASD and OCD relative to control boys for delayed-immediate choices in right ventromedial/lateral orbitofrontal cortex extending into medial/inferior prefrontal cortex, and in cerebellum, posterior cingulate and precuneus. For immediate-delayed choices, patients relative to controls showed reduced activation in anterior cingulate/ventromedial prefrontal cortex reaching into left caudate, which, at a trend level, was more decreased in ASD than OCD patients, and in bilateral temporal and inferior parietal regions.

CONCLUSIONS

This first fMRI comparison between youth with ASD and with OCD, using a reward-based decision-making task, shows predominantly shared neurofunctional abnormalities during TD in key ventromedial, orbital- and inferior fronto-striatal, temporo-parietal and cerebellar regions of temporal foresight and reward processing, suggesting trans-diagnostic neurofunctional deficits.

A model-based analysis of decision making under risk in obsessive-compulsive and hoarding disorders

Attitudes towards risk are highly consequential in clinical disorders thought to be prone to "risky behavior", such as substance dependence, as well as those commonly associated with excessive risk aversion, such as obsessive-compulsive disorder (OCD) and hoarding disorder (HD). Moreover, it has recently been suggested that attitudes towards risk may serve as a behavioral biomarker for OCD. We investigated the risk preferences of participants with OCD and HD using a novel adaptive task and a quantitative model from behavioral economics that decomposes risk preferences into outcome sensitivity and probability sensitivity. Contrary to expectation, compared to healthy controls, participants with OCD and HD exhibited less outcome sensitivity, implying less risk aversion in the standard economic framework. In addition, risk attitudes were strongly correlated with depression, hoarding, and compulsion scores, while compulsion (hoarding) scores were associated with more (less) "rational" risk preferences. These results demonstrate how fundamental attitudes towards risk relate to specific psychopathology and thereby contribute to our understanding of the cognitive manifestations of mental disorders. In addition, our findings indicate that the conclusion made in recent work that decision making under risk is unaltered in OCD is premature.

Shared and disorder-specific task-positive and default mode network dysfunctions during sustained attention in paediatric Attention-Deficit/Hyperactivity Disorder and obsessive/compulsive disorder

Patients with Attention-Deficit/Hyperactivity Disorder (ADHD) and obsessive/compulsive disorder (OCD) share problems with sustained attention, and are proposed to share deficits in switching between default mode and task positive networks. The aim of this study was to investigate shared and disorder-specific brain activation abnormalities during sustained attention in the two disorders. Twenty boys with ADHD, 20 boys with OCD and 20 age-matched healthy controls aged between 12 and 18 years completed a functional magnetic resonance imaging (fMRI) version of a parametrically modulated sustained attention task with a progressively increasing sustained attention load. Performance and brain activation were compared between groups. Only ADHD patients were impaired in performance. Group by sustained attention load interaction effects showed that OCD patients had disorder-specific middle anterior cingulate underactivation relative to controls and ADHD patients, while ADHD patients showed disorder-specific underactivation in left dorsolateral prefrontal cortex/dorsal inferior frontal gyrus (IFG). ADHD and OCD patients shared left insula/ventral IFG underactivation and increased activation in posterior default mode network relative to controls, but had disorder-specific overactivation in anterior default mode regions, in dorsal anterior cingulate for ADHD and in anterior ventromedial prefrontal cortex for OCD. In sum, ADHD and OCD patients showed mostly disorder-specific patterns of brain abnormalities in both task positive salience/ventral attention networks with lateral frontal deficits in ADHD and middle ACC deficits in OCD, as well as in their deactivation patterns in medial frontal DMN regions. The findings suggest that attention performance in the two disorders is underpinned by disorder-specific activation patterns.

The Role of Response Inhibition in Medicated and Unmedicated Obsessive-Compulsive Disorder Patients: Evidence from the Stop-Signal Task

BACKGROUND

Numerous studies have investigated response inhibition (RI) in obsessive-compulsive disorder (OCD), with many reporting that OCD patients demonstrate deficits in RI as compared to controls. However, reported effect sizes tend to be modest and results have been inconsistent, with some studies finding intact RI in OCD. To date, no study has examined the effect of medications on RI in OCD patients.

METHODS

We analyzed results from a stop-signal task to probe RI in 65 OCD patients (32 of whom were medicated) and 58 healthy controls (HCs).

RESULTS

There was no statistically significant difference in stop-signal reaction time between the OCD group and the HC group, or between the medicated and unmedicated OCD patients. However, variability was significantly greater in the medicated OCD group compared to the unmedicated group.

CONCLUSIONS

These results indicate that some samples of OCD patients do not have deficits in RI, making it unlikely that deficient RI underlies repetitive behaviors in all OCD patients. Future research is needed to fully elucidate the impact of medication use on stop-signal performance. Implications for future research on the cognitive processes underlying repetitive thoughts and behaviors are discussed.

Decisional impulsivity and the associative-limbic subthalamic nucleus in obsessive-compulsive disorder: stimulation and connectivity

Why do we make hasty decisions for short-term gain? Rapid decision-making with limited accumulation of evidence and delay discounting are forms of decisional impulsivity. The subthalamic nucleus is implicated in inhibitory function but its role in decisional impulsivity is less well-understood. Here we assess decisional impulsivity in subjects with obsessive compulsive disorder who have undergone deep brain stimulation of the limbic and associative subthalamic nucleus. We show that stimulation of the subthalamic nucleus is causally implicated in increasing decisional impulsivity with less accumulation of evidence during probabilistic uncertainty and in enhancing delay discounting. Subthalamic stimulation shifts evidence accumulation in subjects with obsessive-compulsive disorder towards a functional less cautious style closer to that of healthy controls emphasizing its adaptive nature. Thus, subjects with obsessive compulsive disorder on subthalamic stimulation may be less likely to check for evidence (e.g. checking that the stove is on) with no difference in subjective confidence (or doubt). In a separate study, we replicate in humans (154 healthy controls) using resting state functional connectivity, tracing studies conducted in non-human primates dissociating limbic, associative and motor frontal hyper-direct connectivity with anterior and posterior subregions of the subthalamic nucleus. We show lateralization of functional connectivity of bilateral ventral striatum to right anterior ventromedial subthalamic nucleus consistent with previous observations of lateralization of emotionally evoked activity to right ventral subthalamic nucleus. We use a multi-echo sequence with independent components analysis, which has been shown to have enhanced signal-to-noise ratio, thus optimizing visualization of small subcortical structures. These findings in healthy controls converge with the effective contacts in obsessive compulsive disorder patients localized within the anterior and ventral subthalamic nucleus. We further show that evidence accumulation is associated with anterior associative-limbic subthalamic nucleus and right dorsolateral prefrontal functional connectivity in healthy controls, a region implicated in decision-making under uncertainty. Together, our findings highlight specificity of the anterior associative-limbic subthalamic nucleus in decisional impulsivity. Given increasing interest in the potential for subthalamic stimulation in psychiatric disorders and the neuropsychiatric symptoms of Parkinson’s disease, these findings have clinical implications for behavioural symptoms and cognitive effects as a function of localization of subthalamic stimulation.

Cognitive Dysfunction in Obsessive-Compulsive Disorder

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

Response to Cognitive impulsivity and the behavioral addiction model of obsessive-compulsive disorder: Abramovitch and McKay (2016)

In our recently published article, we investigated the behavioral addiction model of obsessive-compulsive disorder (OCD), by assessing three core dimensions of addiction in patients with OCD healthy participants. Similar to the common findings in addiction, OCD patients demonstrated increased impulsivity, risky decision-making, and biased probabilistic reasoning compared to healthy controls. Thus, we concluded that these results support the conceptualization of OCD as a disorder of behavioral addiction. Here, we answer to Abramovitch and McKay (2016) commentary on our paper and we support our conclusions by explaining how cognitive impulsivity is also a typical feature of addiction and how our results on decision-making and probabilistic reasoning tasks reflect cognitive impulsivity facets that are consistently replicated in OCD and addiction.

Decision-making in patients with temporal lobe epilepsy: Delay gratification ability is not impaired in patients with hippocampal sclerosis

BACKGROUND

Decision-making abilities have rarely been examined in patients with temporal lobe epilepsy related to hippocampal sclerosis (TLE-HS). We aimed to investigate the ability to delay gratification, a decision-making subdomain, in patients with intractable TLE-HS and to verify the association of delay gratification performance and cool executive function tests.

METHODS

We evaluated 27 patients with TLE-HS (mean age: 35.46 [±13.31] years; 7 males) and their cognitive performance was compared with that of 27 age- and gender-matched healthy controls (mean age: 35.33 [±12.05] years; 7 males), without epilepsy and psychiatric disorders. Patients were assessed using the delay discounting task (DDT) and tests of attention, shifting, inhibitory control, and concept formation. Results were correlated with clinical epilepsy variables such as age of onset, epilepsy duration, AED use, history of status epilepticus, febrile seizures, and the presence of generalized seizures. Statistical analysis was performed using one-way ANCOVA with years of education as a confounding factor.

RESULTS

Patients and controls demonstrated similar performance on DDT, showing similar discount rate (p=0.935) and probability rate (p=0.585). Delay gratification was not related to cool executive function tests (Digit Span, Stroop Color Test, Trail Making Test, Wisconsin Card Sorting Test, and Connors' CPT). History of status epilepticus, presence of generalized seizures and higher seizure frequency, age at onset, and epilepsy duration had a significant impact on DDT.

CONCLUSION

Patients with intractable TLE-HS showed unimpaired delay gratification abilities, being able to accept a higher delay and a lower amount of chance for receiving a higher reward in the future. Clinical variables related to the epilepsy severity impacted the performance on delay gratification. Impairment on cool aspects of executive function was unrelated to this decision-making domain.