Cognitive flexibility differentiates young adults exhibiting obsessive-compulsive behaviors from controls

Immersive exposure to simulated visual hallucinations modulates high-level human cognition

Psychedelic drugs offer valuable insights into consciousness, but disentangling their causal effects on perceptual and high-level cognition is nontrivial. Technological advances in virtual reality (VR) and machine learning have enabled the immersive simulation of visual hallucinations. However, comprehensive experimental data on how these simulated hallucinations affects high-level human cognition is lacking. Here, we exposed human participants to VR panoramic videos and their psychedelic counterparts generated by the DeepDream algorithm. Participants exhibited reduced task-switching costs after simulated psychedelic exposure compared to naturalistic exposure, consistent with increased cognitive flexibility. No significant differences were observed between naturalistic and simulated psychedelic exposure in linguistic automatic association tasks at word and sentence levels. Crucially, visually grounded high-level cognitive processes were modulated by exposure to simulated hallucinations. Our results provide insights into the interdependence of bottom-up and top-down cognitive processes and altered states of consciousness without pharmacological intervention, potentially informing both basic neuroscience and clinical applications.

Theory of Mind Abilities May Predict Treatment Outcomes in Adolescents With Obsessive-Compulsive Disorder: A Follow-Up Study

AIMS

Researchers report varying levels of cognitive flexibility and theory of mind (ToM) deficiencies in adolescents with obsessive-compulsive disorder (OCD). This research set out to investigate the impact of these variables on the disorder's outcomes.

METHOD

The study involved 39 adolescents with OCD and 40 healthy controls. We assessed the case group at the initial visit to the outpatient clinic and again at the end of the first year of treatment. The Children's Yale-Brown Obsessive-Compulsive Scale (CY-BOCS) was applied to assess OCD symptom distribution and severity. The Reading the Mind in the Eyes of Children Test (RME-CT) was applied to evaluate ToM skills, and the Cognitive Flexibility Scale (CFS) was employed to evaluate cognitive flexibility levels.

RESULTS

Baseline RME-CT and CFS scores were significantly lower in adolescents with OCD compared to the control group (p = 0.002 p = 0.001, respectively). At the end of the 1-year follow-up, RME-CT and CFS scores increased significantly in the adolescents with OCD (p < 0.001, p = 0.003, respectively). A significant negative correlation was observed between the initial RME-CT scores and the Y-BOCS scores at the end of the 1-year follow-up (p < 0.001). The initial RME-CT score had a significant negative predictive effect on the subsequent severity of OCD (β = -0.711, p < 0.001).

CONCLUSIONS

The research revealed poorer long-term prognoses for OCD in adolescents who exhibit low ToM skills. In conclusion, the results indicate that ToM skills may serve as a predictive factor for long-term treatment outcomes among adolescents diagnosed with OCD.

Comparison of the effectiveness of acceptance and commitment therapy (ACT) with metacognitive therapy (MCT) in objective cognitive information processing style of obsessive-compulsive patients (OCD)

BACKGROUND

In recent studies, the deficit in the cognitive process has been investigated as one of the etiological hypotheses in a wide range of obsessive-compulsive disorders (OCD). This study aimed to compare the effectiveness of acceptance and commitment therapy (ACT) and metacognitive therapy (MCT) on objective cognitive information processing style in obsessive-compulsive patients.

MATERIALS AND METHODS

This quasi-experimental study with a pre-test and post-test plan and a control group was conducted on 45 patients with OCD, matched with gender, age, and educational and marital status. The samples in three groups were selected using the convenience sampling method. Finally, the study participants were randomly divided into two experimental groups and one control group and assessed using Pacini and Epstein's rational experimental Inventory (REI) in two stages, pre-test, and post-test. The experimental groups received ACT and MCT weekly during eight and seven sessions and in a group.

RESULTS

The results showed that ACT and MCT are effective at a significant level in the objective cognitive information processing style of obsessive-compulsive patients (P < 0.05). The post-test results showed that the effect of ACT in changing rational processing style is more effective than MCT treatment. Also, the effect of ACT on intuitive processing style changes was greater than on MCT treatment.

CONCLUSION

The findings of this study indicate that ACT and MCT cause a significant change in intuitive style to rationalism in the thematic processing of cognitive information of obsessive-compulsive patients. According to the results, both methods of treatment improve the research variables in these patients.

Medial septum activation improves strategy switching once strategies are well-learned via bidirectional regulation of dopamine neuron population activity

Strategy switching is a form of cognitive flexibility that requires inhibiting a previously successful strategy and switching to a new strategy of a different categorical modality. It is dependent on dopamine (DA) receptor activation and release in ventral striatum and prefrontal cortex, two primary targets of ventral tegmental area (VTA) DA projections. Although the circuitry that underlies strategy switching early in learning has been studied, few studies have examined it after extended discrimination training. This may be important as DA activity and release patterns change across learning, with several studies demonstrating a critical role for substantia nigra pars compacta (SNc) DA activity and release once behaviors are well-learned. We have demonstrated that medial septum (MS) activation simultaneously increased VTA and decreased SNc DA population activity, as well as improved reversal learning via these actions on DA activity. We hypothesized that MS activation would improve strategy switching both early in learning and after extended training through its ability to increase VTA DA population activity and decrease SNc DA population activity, respectively. We chemogenetically activated the MS of male and female rats and measured their performance on an operant-based strategy switching task following 1, 10, or 15 days of discrimination training. Contrary to our hypothesis, MS activation did not affect strategy switching after 1 day of discrimination training. MS activation improved strategy switching after 10 days of training, but only in females. MS activation improved strategy switching in both sexes after 15 days of training. Infusion of bicuculline into the ventral subiculum (vSub) inhibited the MS-mediated decrease in SNc DA population activity and attenuated the improvement in strategy switching. Intra-vSub infusion of scopolamine inhibited the MS-mediated increase in VTA DA population activity but did not affect the improvement in strategy switching. Intra-vSub infusion of both bicuculline and scopolamine inhibited the MS-mediated effects on DA population activity in both the SNc and VTA and completely prevented the improvement in strategy switching. These data indicate that MS activation improves strategy switching once the original strategy has been sufficiently well-learned, and that this may occur via the MS's regulation of DA neuron responsivity.

Obsessive-compulsive and related disorder symptoms in the perinatal period: prevalence and associations with postpartum functioning

Obsessive-compulsive disorder (OCD) symptoms are more likely to develop or be exacerbated during pregnancy and the postpartum period, which can cause significant distress and impairment. However, the disorders grouped with OCD in the DSM-5, obsessive-compulsive and related disorders (OCRD; e.g., hoarding disorder (HD), body dysmorphic disorder (BDD), trichotillomania (TTM), excoriation disorder (ED)), have rarely been examined in the perinatal period. This study aimed to explore (1) the prevalence of all clinically significant OCRD symptoms in pregnancy and the postpartum period and (2) the correlations between OCRD psychopathology and postpartum functioning. Participants were recruited during their second trimester of pregnancy from a Midwestern medical center. Participants completed an online questionnaire and a semi-structured clinical interview during pregnancy (28-32 weeks' gestation, N = 276) and the postpartum period (6-8 weeks, N = 221). BDD and OCD symptoms were the most prevalent. In pregnancy, 14.9% (N = 41) of participants endorsed clinically significant BDD symptoms and 6.2% (N = 17) endorsed clinically significant OCD symptoms. In the postpartum period, 11.8% (N = 26) endorsed clinically significant BDD symptoms and 14% (N = 31) endorsed clinically significant OCD symptoms. Poorer postpartum functioning was associated with elevated OCRD symptoms in pregnancy and postpartum. OCRD symptoms occur during pregnancy and the postpartum period at rates similar or higher than other life periods. Elevated OCRD symptoms are associated with poorer postpartum functioning across domains. Future research should explore how all OCRD symptoms may affect functioning in the perinatal period, not only OCD symptoms.

Identifying subtypes of trichotillomania (hair pulling disorder) and excoriation (skin picking) disorder using mixture modeling in a multicenter sample

Body-focused repetitive behavior disorders (BFRBs) include Trichotillomania (TTM; Hair pulling disorder) and Excoriation (Skin Picking) Disorder (SPD). These conditions are prevalent, highly heterogeneous, under-researched, and under-treated. In order for progress to be made in optimally classifying and treating these conditions, it is necessary to identify meaningful subtypes. 279 adults (100 with TTM, 81 with SPD, 40 with both TTM and SPD, and 58 controls) were recruited for an international, multi-center between-group comparison using mixture modeling, with stringent correction for multiple comparisons. The main outcome measure was to examine distinct subtypes (aka latent classes) across all study participants using item-level data from gold-standard instruments assessing detailed clinical measures. Mixture models identified 3 subtypes of TTM (entropy 0.98) and 2 subtypes of SPD (entropy 0.99) independent of the control group. Significant differences between these classes were identified on measures of disability, automatic and focused symptoms, perfectionism, trait impulsiveness, and inattention and hyperactivity. These data indicate the existence of three separate subtypes of TTM, and two separate subtypes of SPD, which are distinct from controls. The identified clinical differences between these latent classes may be useful to tailor future treatments by focusing on particular traits. Future work should examine whether these latent subtypes relate to treatment outcomes, or particular psychobiological findings using neuroimaging techniques.

The medial septum enhances reversal learning via opposing actions on ventral tegmental area and substantia nigra dopamine neurons

Cognitive flexibility deficits are one of the most pervasive symptoms across psychiatric disorders, making continued investigation of the circuitry underlying this function a top priority. Medial septum (MS) lesions lead to perseverative, inflexible-type behavior; however, a role for this region in cognitive flexibility circuitry has never been examined. We activated the MS (DREADDs) and measured performance in a T-maze spatial reversal learning task in male Sprague-Dawley rats. Systemic activation of the MS (CNO) significantly decreased both trials to perform a reversal and entries into the previously baited arm. Intra-ventral subiculum CNO enhanced reversal learning in the same manner as systemic CNO and also significantly increased ventral tegmental area and decreased substantia nigra dopamine neuron population activity. Finally, co-injection of the D1 antagonist SCH23390 with CNO prevented the enhanced reversal learning performance seen in the previous two experiments. Taken together, these data suggest a key role for the MS in cognitive flexibility, and suggest that MS-mediated changes in midbrain dopamine neuron population activity could be one mechanism by which this occurs.

Genetic analysis for cognitive flexibility in the trail-making test in attention deficit hyperactivity disorder patients from single nucleotide polymorphism, gene to pathway level

Objectives: Investigation of the genetic basis of endophenotype and analysis the pathways with multiple genes of small effects might increase the understanding of the genetic basis of attention deficit hyperactivity disorder (ADHD). Here we aimed to explore the genetic basis of cognitive flexibility in ADHD at the single nucleotide polymorphism (SNP), gene and pathway levels. Methods: The trail-making test was used to test the cognitive flexibility of 788 ADHD patients. A genome-wide association analysis of cognitive flexibility was conducted for 644,166 SNPs. Results: The top SNP rs2049161 (P = 5.08e-7) involved gene DLGAP1 and the top gene CADPS2 in the gene-based analysis resulted in much literature evidence of associations with psychiatric disorders. Gene expression and network analysis showed their contribution to cognition function. The interval-enrichment analysis highlighted a potential contribution of 'adenylate cyclase activity' and ADCY2 to cognitive flexibility. Candidate pathway-based analysis for all SNPs found that glutamate system-, neurite outgrowth- and noradrenergic system-related pathways were significantly associated with cognitive flexibility (FDR <0.05), among which the neurite outgrowth pathway was also associated with ADHD symptoms. Conclusions: This study provides evidence for the genes and pathways associated with cognitive flexibility and facilitate the uncovering of the genetic basis of ADHD.

The Flexibility Scale: Development and Preliminary Validation of a Cognitive Flexibility Measure in Children with Autism Spectrum Disorders

Flexibility is a key component of executive function, and is related to everyday functioning and adult outcomes. However, existing informant reports do not densely sample cognitive aspects of flexibility; the Flexibility Scale (FS) was developed to address this gap. This study investigates the validity of the FS in 221 youth with ASD and 57 typically developing children. Exploratory factor analysis indicates a five-factor scale: Routines/rituals, transitions/change, special interests, social flexibility, and generativity. The FS demonstrated convergent and divergent validity with comparative domains of function in other measures, save for the Generativity factor. The FS discriminated participants with ASD and controls. Thus, this study suggests the FS may be a viable, comprehensive measure of flexibility in everyday settings.

DLGAP1 and NMDA receptor-associated postsynaptic density protein genes influence executive function in attention deficit hyperactivity disorder

Objective

To explore the association of DLGAP1 gene with executive function (EF) in attention deficit hyperactivity disorder (ADHD) children.

Method

A total of 763 ADHD children and 140 healthy controls were enrolled. The difference of EF between ADHD and controls was analyzed using the analysis of covariance (ANCOVA), with IQ, sex, and age as covariates. Both the associations of SNPs with EF and three symptom traits of ADHD were conducted using an additive linear regression model by PLINK with the same covariates as ANCOVA.

Results

Compared with controls, children with ADHD showed poorer cognitive flexibility and inhibition. Two SNPs (rs2049161, p-value = 5.08e-7, adjusted p-value = 1.63e-4, rs16946051, p-value = 5.18e-7, adjusted p-value = 1.66e-4) survived multiple tests in Trail Making Test. Both SNPs also showed association with TOH (rs2049161, p = 6.82e-4, rs16946051, p = 7.91e-4). Set-based analysis for gene DLGAP1 and its functional pathway DLGAP1-DLG4-NMDA showed they were associated with cognitive flexibility at both gene (p = .0057) and pathway level (p = .0321). Furthermore, the gene and pathway also showed association with ADHD symptom score. The associated SNPs and their LD proxies were related to the expression of DLGAP1 in medulla and frontal cortex.

Conclusion

Children with ADHD showed deficit in EF, especially, cognitive flexibility and inhibition. DLGAP1 was associated with cognitive flexibility and plan, and the role of DLGAP1 might be implemented through the complex of DLGAP1-DLG4-NMDA.

Six Years of Research on the National Institute of Mental Health's Research Domain Criteria (RDoC) Initiative: A Systematic Review

Six years have passed since the National Institute of Mental Health (NIMH) in the United States launched the Research Domain Criteria (RDoC) initiative. The RDoC introduces a framework for research on the biology of mental illness that integrates research findings across multiple levels of information. The framework outlines constructs that represent specific quantifiable dimensions of behavior (e.g., responses to acute threat, cognitive control) and corresponding units of analysis that can be used to study the constructs, beginning at the levels of genes, molecules, cells, circuits and physiology, and moving up to behaviors and self-reports. In this systematic review, a literature search was conducted to synthesize empirical research published since the proposal of the framework that incorporated the RDoC. Forty-eight peer-reviewed scholarly articles met eligibility criteria for the review. Studies differed according to whether they analyzed RDoC constructs and units of analysis within vs. between clinically-diagnosed and non-psychiatric samples. The most commonly studied constructs were subsumed within the domains of Negative Valence Systems, Positive Valence Systems and Cognitive Systems, providing initial results which primarily connected genetics, brain circuits and physiology research findings with behavior and self-reports. Prospects for future research adopting the RDoC matrix and utilizing a dimensional approach to studying the biology of mental illness are discussed.

Modeling neurodevelopmental cognitive deficits in tasks with cross-species translational validity

Numerous psychiatric disorders whose cognitive dysfunction links to functional outcome have neurodevelopmental origins including schizophrenia, autism and bipolar disorder. Treatments are needed for these cognitive deficits, which require development using animal models. Models of neurodevelopmental disorders are as varied and diverse as the disorders themselves, recreating some but not all aspects of the disorder. This variety may in part underlie why purported procognitive treatments translated from these models have failed to restore functioning in the targeted patient populations. Further complications arise from environmental factors used in these models that can contribute to numerous disorders, perhaps only impacting specific domains, while diagnostic boundaries define individual disorders, limiting translational efficacy. The Research Domain Criteria project seeks to 'develop new ways to classify mental disorders based on behavioral dimensions and neurobiological measures' in hopes of facilitating translational research by remaining agnostic toward diagnostic borders derived from clinical presentation in humans. Models could therefore recreate biosignatures of cognitive dysfunction irrespective of disease state. This review highlights work within the field of neurodevelopmental models of psychiatric disorders tested in cross-species translational cognitive paradigms that directly inform this newly developing research strategy. By expounding on this approach, the hopes are that a fuller understanding of each model may be attainable in terms of the cognitive profile elicited by each manipulation. Hence, conclusions may begin to be drawn on the nature of cognitive neuropathology on neurodevelopmental and other disorders, increasing the chances of procognitive treatment development for individuals affected in specific cognitive domains.

Detrimental effect of clomipramine on hippocampus-dependent learning in an animal model of obsessive-compulsive disorder induced by sensitization with d2/d3 agonist quinpirole

Quinpirole (QNP) sensitization is one of the commonly used animal models of obsessive-compulsive disorder (OCD). We have previously shown that QNP-sensitized animals display a robust cognitive flexibility deficit in an active place avoidance task with reversal in Carousel maze. This is in line with numerous human studies showing deficits in cognitive flexibility in OCD patients. Here we explored the effect of clomipramine, an effective OCD drug that attenuates compulsive checking in QNP, on sensitized rats in acquisition and reversal performances in an active place avoidance task. We found that the addition of clomipramine to QNP-sensitization impairs acquisition learning to a degree that reversal learning could not be tested. In a hippocampal-independent two-way active avoidance task clomipramine did not have an effect on acquisition learning in QNP-treated rats; suggesting that the detrimental effect of clomipramine is hippocampus based. We also tested the effect of risperidone in QNP-sensitized animals, which is not effective in OCD treatment. Risperidone also marginally impaired acquisition learning of QNP-sensitized animals, but not reversal. Moreover, we explored the effect of the augmentation of clomipramine treatment with risperidone in QNP-sensitized rats- a common step in treating SRI-unresponsive OCD patients. Only under this treatment regime animals were unimpaired in both acquisition and reversal learning. Augmentation of SRI with neuroleptics therefore could be beneficial for improving cognitive flexibility, and possibly be considered a first line of treatment in patients with reduced cognitive flexibility.

Cognitive and emotional impairments in obsessive-compulsive disorder: Evidence from functional brain alterations

There is a common agreement on the existence of dysfunctional cortico-striatal-thalamus-cortical pathways in OCD. Despite this consensus, recent studies showed that brain regions other than the CSTC loops are needed to understand the complexity and diversity of cognitive and emotional deficits in OCD. This review presents examples of research using functional neuroimaging, reporting abnormal brain processes in OCD that may underlie specific cognitive/executive (inhibitory control, cognitive flexibility, working memory), and emotional impairments (fear/defensive, disgust, guilt, shame). Studies during resting state conditions show that OCD patients have alterations in connectivity not only within the CSTC pathways but also in more extended resting state networks, particularly the default mode network and the fronto-parietal network. Additionally, abnormalities in brain functioning have been found in several cognitive and emotionally task conditions, namely: inhibitory control (e.g., CSTC loops, fronto-parietal networks, anterior cingulate); cognitive flexibility (e.g., CSTC loops, extended temporal, parietal, and occipital regions); working memory (e.g., CSTC loops, frontal parietal networks, dorsal anterior cingulate); fear/defensive (e.g., amygdala, additional brain regions associated with perceptual - parietal, occipital - and higher level cognitive processing - prefrontal, temporal); disgust (e.g., insula); shame (e.g., decrease activity in middle frontal gyrus and increase in frontal, limbic, temporal regions); and guilt (e.g., decrease activity anterior cingulate and increase in frontal, limbic, temporal regions). These findings may contribute to the understanding of OCD as both an emotional (i.e., anxiety) and cognitive (i.e., executive control) disorder.

IMPAIRED EXECUTIVE FUNCTIONING IN PEDIATRIC TRICHOTILLOMANIA (HAIR PULLING DISORDER)

BACKGROUND

No neurocognitive examinations of pediatric trichotillomania (hair pulling disorder; HPD) have taken place. As a result, science's understanding of the underlying pathophysiology associated with HPD in youths is greatly lacking. The present study seeks to begin to address this gap in the literature via examination of executive functioning in a stimulant-free sample of children with HPD.

METHODS

Sixteen and 23 children between 9 and 17 years of age meeting DSM-5 diagnostic criteria for HPD or classified as a healthy control, respectively, were recruited (N = 39) to complete structured interviews, self-reports, and a subset of tests from the Cambridge Automatic Neurocognitive Test Assessment Battery (CANTAB) assessing cognitive flexibility/reversal learning (intradimensional/extradimensional; IED), working memory (spatial span; SSP), and planning and organization (Stocking of Cambridge; SOC).

RESULTS

Hierarchical regression analyses indicated that, after controlling for appropriate covariates, diagnostic status predicted impaired performance on both the IED (reversal learning only) and SOC (planning and organization) but failed to predict cognitive flexibility or working memory capacity. Correlational analyses revealed that pulling severity was strongly related to working memory capacity, while disparate relationships between pulling styles (automatic, focused pulling) were evident with respect to working memory and planning and organization.

CONCLUSIONS

Children with HPD performed more poorly on tasks of executive functioning as compared to controls. Correlational analyses suggest potentially distinct pathophysiology underlying automatic and focused pulling warranting further research. Limitations and future areas of inquiry are discussed.