Obsessive–compulsive tendencies are associated with a focused information processing strategy

Does responsibility for potential harm attenuate the effects of repeated checking on metamemory and automatization?

BACKGROUND AND OBJECTIVES

Repeated checking results in large reductions in metamemory variables (confidence, details, and vividness). It has been suggested that the underlying mechanism is gradual automatization. At the same time, individuals with obsessive-compulsive disorder (OCD) are reluctant to automatize routine processes. The aim was to investigate whether high responsibility for potential harm, typical of OCD, would attenuate the effects of repeated checking on metamemory variables and automatization.

METHODS

One hundred seventy-five participants were initially provided with a cover story that put the subsequent virtual checking task in a context of potential harm for not checking properly. Participants were randomly allocated to four experimental groups (varying high and low responsibility, relevant and irrelevant checking) and performed a virtual checking task repeatedly, using either identical stimuli (relevant checking) or different stimuli (irrelevant checking) between the first and final checking trial. Metamemory variables were rated on visual analogue scales, and response latencies were assessed to establish automatization.

RESULTS

Larger reductions in metamemory variables following relevant checking compared to irrelevant checking replicated previous findings. High responsibility did not affect these results. Large reductions in response latencies across the checking trials (automatization) were also independent of the perceived responsibility.

LIMITATIONS

We did not include individuals with OCD.

CONCLUSIONS

Since responsibility did not influence the effects of repeated checking on metamemory variables, findings are consistent with the idea that automatization remains a plausible explanation of the effects of repeated checking on metamemory variables in individuals with OCD.

Compulsive rituals in Obsessive-Compulsive Disorder - A qualitative exploration of thoughts, feelings and behavioral patterns

BACKGROUND AND OBJECTIVES

Rituals are common among healthy individuals and across cultures and often serve adaptive purposes. In individuals with obsessive-compulsive disorder (OCD), rituals become compulsive, time-consuming and distressing, and may lead to functional impairment. Previous research has examined the functions and characteristics of compulsive rituals, but there is paucity of in-depth, first-person reports about this topic.

METHOD

We used a qualitative approach to explore thoughts, feelings, and behavioral patterns that characterize OCD rituals. Ten individuals with OCD participated in a semi-structured interview that focused on their most prominent compulsive ritual. The interviews were subjected to a thematic analysis.

RESULTS

Eight themes emerged from the analysis and were organized in two main categories: Micro Level perspective, comprising triggers, attention, emotional changes, and stopping criteria; and Macro Level perspective, comprising feelings and perceptions, change over time, motives, and inhibitors. The findings shed light on the role of fixed rules and feelings of "completeness" in OCD rituals, the nature of emotional and attentional characteristics during rituals performance, and the evolution of compulsive rituals over time.

LIMITATIONS

This study used a qualitative approach based on a small number of participants, which limits the generalizability of the findings.

CONCLUSION

Our results, if replicated, may have clinical implications. The reported patterns of anxiety reduction during ritual performance may contribute to the fine-tuning of CBT for OCD. The findings concerning the nature of attention during ritual performance and the development of rituals over time may be important for understanding the mechanisms that maintain compulsive rituals.

Exploring the structure of the university-students obsessive-compulsive tendency scale in Iranian university students: a network analysis study

INTRODUCTION

A risk factor for developing obsessive-compulsive disorder (OCD) in non-clinical samples is obsessive-compulsive tendencies (OCT). An OCT scale has recently been developed for university students (UOC) and showed promising psychometric properties. However, no validated Persian language scale evaluates OCT in non-clinical samples. Accordingly, this study aimed to validate the Persian version of the UOC in Iranian university students.

METHODS

Three hundred sixty-eight university students (54.6% females, mean ages: 22.4 ± 4.51) entered the study. The Persian version of UOC was evaluated concerning the structure of Exploratory Factor Analysis (EFA), Confirmatory factor analysis (CFA), and Exploratory graph analysis (EGA). Regarding the construct validity, the concurrent validity was assessed between the UOC and The Obsessive-Compulsive Inventory-Revised (OCI-R), Kessler Psychological Distress Scale (K10), and Yale-Brown Obsessive-Compulsive Scale (Y-BOCS). We calculated Cronbach's alpha to evaluate the reliability of the UOC. All statistical calculations were done in R programming language (in R-Studio Desktop version 4.2.1).

RESULTS

The Persian version of UOC showed a convenient internal consistency with Cronbach's alpha coefficient for the total scale 0.88. UOC scores were significantly correlated with OCI-R, K-10, and YBOCS. The EFA and EGA showed four and three-factor solutions with 25 and 28 items, respectively. Also, CFA showed that these two solutions were reliable, and the three-factors solution showed higher fit indexes. Finally, the results showed that item-27 was the most central item in the UOC network structure.

CONCLUSION

The findings from the present study indicated that the Persian version of UOC has acceptable psychometric properties. So, this scale can be used for examining obsessive-compulsive tendencies in Iranian university students.

Impaired Non-Selective Response Inhibition in Obsessive-Compulsive Disorder

Two prominent features of obsessive-compulsive disorder (OCD) are the inability to inhibit intrusive thoughts and behaviors and pathological doubt or intolerance of uncertainty. Previous study showed that uncertain context modeled by equiprobable presentation of excitatory (Go) and inhibitory (NoGo) stimuli requires non-selective response inhibition in healthy subjects. In other words, it requires transient global inhibition triggered not only by excitatory stimuli but also by inhibitory stimuli. Meanwhile, it is unknown whether OCD patients show abnormal brain activity of the non-selective response inhibition system. In order to test this assumption, we performed an fMRI study with an equiprobable Go/NoGo task involving fourteen patients with OCD and compared them with 34 healthy controls. Patients with OCD showed pathological slowness in the Go/NoGo task. The non-selective response inhibition system in OCD included all brain areas seen in healthy controls and, in addition, involved the right anterior cingulate cortex (ACC) and the anterior insula/frontal operculum (AIFO). Moreover, a between-group comparison revealed hypoactivation of brain regions within cingulo-opercular and cortico-striato-thalamo-cortical (CSTC) circuits in OCD. Among hypoactivated areas, the right ACC and the right dorsolateral prefrontal cortex (DLPFC) were associated with non-selective inhibition. Furthermore, regression analysis showed that OCD slowness was associated with decreased activation in cingulate regions and two brain areas related to non-selective inhibition: the right DLPFC and the right inferior parietal lobule (IPL). These results suggest that non-selective response inhibition is impaired in OCD, which could be a potential explanation for a relationship between inhibitory deficits and the other remarkable characteristic of OCD known as intolerance of uncertainty.

Effects of a three-week executive control training on adaptation to task difficulty and emotional interference

Intact executive functions are characterized by flexible adaptation to task requirements, while these effects are reduced in internalizing disorders. Furthermore, as executive functions play an important role in emotion regulation, deficits in executive functions may contribute to symptom generation in psychological disorders through increased emotional interference. Thus, the present study investigated transfer effects of a three-week executive control training on adaptation to task difficulty and emotional interference in healthy participants (n = 24) to further explore the training's suitability for clinical application. To assess the adaptation to task difficulty, the proportion congruency effect on behavioral data (response times, error rates) and ERP measures (N2, CRN) was assessed in a flanker task with varying frequency of incompatible trials (25%, 75%). To quantify emotional interference, flanker stimuli were superimposed on neutral or negative pictures. Replicating previous results, the training increased interference control as indexed by decreased response times and errors rates, increased N2 amplitude and decreased CRN amplitude in incompatible trials after training. Proportion congruency effects were weaker than expected and not affected by the training intervention. The training lead to a shift in the time-point of emotional interference: before training negative pictures lead to a reduction in CRN amplitude, while after training this reduction was observed for the N2. This pattern illustrates that the training leads to a change in task processing mode from predominant response-related cognitive control to predominant stimulus-related cognitive control (N2), indicating a proactive processing mode.

Development of a scale to assess obsessive-compulsive tendencies among Japanese university students

Obsessive-compulsive (OC) tendencies refer to obsessions and compulsions in a nonclinical group, which are risk factors for obsessive-compulsive disorder (OCD). OC tendencies and OC symptoms are mainly assessed using five factors: ordering, obsessions, cleaning, hoarding, and checking. However, since hoarding is now classified as an independent diagnosis in the DSM-V, this factor was not included and was instead replaced by indecisiveness. Furthermore, many established scales used for measuring OC tendencies were originally created for OCD patients; thus, they cannot adequately capture OC tendencies. Therefore, this study aimed to develop a scale to assess OC tendencies among Japanese university students with a revised five-factor structure: ordering, obsessions, cleaning, indecisiveness, and checking. We examined the factor structure, reliability, criterion-related validity, and convergent validity of the OC tendencies scale by administering two surveys. In Survey 1 (N = 216), an exploratory factor analysis (EFA) was conducted to examine the criterion-related and convergent validity and reliability of the OC tendencies scale. In Survey 2 (N = 202), a confirmatory factor analysis (CFA) was conducted. EFA and CFA utilized a five-factor structure comprising checking, ordering, indecisiveness, cleaning, and obsessions. Correlations with other scales indicated that the OC tendencies scale had efficient convergent validity, criterion-related validity, internal consistency, and test-retest reliability. This study validated the five-factor structure of OC tendency in Japanese university students. However, indecisiveness was also strongly correlated with trait-anxiety. As this scale is easy to administer among large groups, it has the potential to contribute to mental health support for university students by measuring OC tendencies experienced on a daily basis, which have not been adequately measured in the past.

The metacontrol hypothesis as diagnostic framework of OCD and ADHD: A dimensional approach based on shared neurobiological vulnerability

Obsessive-compulsive disorder (OCD) and attention-deficit hyperactivity disorder (ADHD) are multi-faceted neuropsychiatric conditions that in many aspects appear to be each other's antipodes. We suggest a dimensional approach, according to which these partially opposing disorders fall onto a continuum that reflects variability regarding alterations of cortico-striato-thalamo-cortical (CSTC) circuits and of the processing of neural noise during cognition. By using theoretical accounts of human cognitive metacontrol, we develop a framework according to which OCD can be characterized by a chronic bias towards exaggerated cognitive persistence, equivalent to a high signal-to-noise ratio (SNR)-which facilitates perseverative behaviour but impairs mental flexibility. In contrast, ADHD is characterized by a chronic bias towards inflated cognitive flexibility, equivalent to a low SNR-which increases behavioural variability but impairs the focusing on one goal and on relevant information. We argue that, when pharmacology is not feasible, novel treatments of these disorders may involve methods to manipulate the signal-to-noise ratio via non-invasive brain stimulation techniques, in order to normalize the situational imbalance between cognitive persistence and cognitive flexibility.

Habitual or hyper-controlled behavior: OCD symptoms and explicit sequence learning

BACKGROUND AND OBJECTIVES

This study examined whether ritualistic behaviors characteristic of obsessive-compulsive disorder (OCD) are a product of dysfunctional goal-directed behavior leading to habitual behavior (Gillan & Robbins, 2014). We used an explicit motor sequence learning task to investigate the repetition of chunked action sequences across the OC spectrum. As sequential motor behavior is practiced, action movements appear to get bundled together, and the initial movement of the sequence activates the entire sequence, leaving it relatively insensitive to change. Therefore, compulsive behavior in OCD may be a result of failing to inhibit the full activation of an extensively learned action sequence.

METHODS

Fifty-seven participants across the range of OCD symptoms practiced one sequence and then tested on a novel sequence in which one of the middle movements was omitted. Optimal performance for the new sequence required goal-directed inhibition of the original sequence and goal-directed execution of the new sequence instead. To manipulate activation of goal-directed behavior, we added a dual-task condition with a competing auditory tonal N-Back task. Data were analyzed using mixed-effects models.

RESULTS

Although we did observe expected learning patterns during learning of the original sequence, slower reaction times for the new sequences, and higher errors in the dual-task condition, performance was not significantly related to either obsessive-compulsive symptoms or distress symptoms.

LIMITATIONS

The current study used an analog sample; replication in a treatment seeking sample is warranted.

CONCLUSIONS

These findings challenge the goal-directed dysfunction model of OCD.

Error-Related Brain Activity in Patients With Obsessive-Compulsive Disorder and Unaffected First-Degree Relatives: Evidence for Protective Patterns

Background

Indicators of increased error monitoring are associated with obsessive-compulsive disorder (OCD), as shown in electroencephalography and functional magnetic resonance imaging studies. As most studies used strictly controlled samples (excluding comorbidity and medication), it remains open whether these findings extend to naturalistic settings. Thus, we assessed error-related brain activity in a large, naturalistic OCD sample. We also explored which activity patterns might qualify as vulnerability endophenotypes or protective factors for the disorder. To this aim, a sample of unaffected first-degree relatives of patients with OCD was also included.

Methods

Participants (84 patients with OCD, 99 healthy control participants, and 37 unaffected first-degree relatives of patients with OCD) completed a flanker task while blood oxygen level–dependent responses were measured with functional magnetic resonance imaging. Aberrant error-related brain activity in patients and relatives was identified.

Results

Patients with OCD showed increased error-related activity in the supplementary motor area and within the default mode network, specifically in the precuneus and postcentral gyrus. Unaffected first-degree relatives showed increased error-related activity in the bilateral inferior frontal gyrus.

Conclusions

Increased supplementary motor area and default mode network activity in patients with OCD replicates previous studies and might indicate excessive error signals and increased self-referential error processing. Increased activity of the inferior frontal gyrus in relatives may reflect increased inhibition. Impaired response inhibition in OCD has been demonstrated in several studies and might contribute to impairments in suppressing compulsive actions. Thus, increased inferior frontal gyrus activity in the unaffected relatives of patients with OCD may have contributed to protection from symptom development.

Intact capacity for implicit learning in obsessive-compulsive disorder

BACKGROUND AND OBJECTIVES

Individuals with OCD tend to rely on explicit processing when performing implicit learning tasks. However, it is unclear whether this tendency reflects impaired capacity for implicit processing or a preference toward explicit processing. We sought to use a psychometrically valid task to examine the hypothesis that individuals with OCD have intact capacity for implicit learning.

METHODS

Twenty-four participants with OCD and 24 non-psychiatric controls completed a modified artificial grammar learning task where acquisition and retrieval of the underlying grammatical rules are considered strictly implicit. In an exploratory condition designed to examine the effect of nudging participants toward controlled processing, 12 participants in each group were told that the stimuli presented at acquisition were composed according to grammatical rules and were encouraged to identify these rules.

RESULTS

As predicted, participants with OCD acquired and expressed knowledge of the grammatical rule, demonstrating intact capacity for implicit learning, with no differences found between the OCD and controls on the extent of implicit learning. The exploratory intentional learning instructions had no effect, as participants in this condition were unable to adhere to the instructions, supporting the robust implicit nature of the artificial grammar learning task.

LIMITATIONS

The relatively small sample size did not allow comparisons between OCD symptom subtypes.

CONCLUSIONS

Our results provide evidence for intact implicit learning in OCD, and challenge previous studies suggesting a general deficiency in implicit learning in OCD.

Effects of adaptive and non-adaptive three-week executive control training on interference control: Evidence from the N2, CRN, and ERN

The current pilot study investigated if interference control can be improved by a three-week at-home training comprising a flanker and a n-back task in healthy adults, thus exploring the training's suitability for future clinical application, i.e. as a treatment augmentation for psychological disorders. As training gains are assumed to be modulated by the amount of mismatch between task demands and brain resources, an adaptive and a non-adaptive training were contrasted in separate experiments. In the adaptive training, task difficulty was continuously adapted to participants' performance. In the non-adaptive training procedure, task difficulty remained stable on the lowest difficulty level. As deficits in interference control in psychological disorders often predominantly manifest on the electrophysiological level, the impact of the training procedures on medio-frontal negativities (N2, CRN, ERN) was investigated in addition to behavioral measures. The adaptive training led to significant improvements in interference control, as reflected in reduced response times and error rates in incompatible trials. This was accompanied by specific and complementary changes in medio-frontal negativities: After the adaptive training the N2 in incompatible trials was larger and the CRN in incompatible trials was reduced. The non-adaptive training procedure led to generally faster response times but also an increased error rate, indicating a speed-accuracy trade-off. This was accompanied by global changes to medio-frontal negativities irrespective of compatibility, possibly indicating task disengagement. Taken together, the current studies demonstrate that an adaptive training procedure can improve interference control thereby opening up possible clinical applications.

The effects of cognitive behavioral therapy on the whole brain structural connectome in unmedicated patients with obsessive-compulsive disorder

Cognitive behavioral therapy (CBT) is considered a first-line treatment for patients with obsessive-compulsive disorder (OCD), and it possesses advantages over pharmacological treatments in stronger tolerance to distress, lower rates of drop out and relapse, and no physical "side-effects". Previous studies have reported CBT-related alterations in focal brain regions and connections. However, the effects of CBT on whole-brain structural networks have not yet been elucidated. Here, we collected diffusion MRI data from 34 unmedicated OCD patients before and after 12 weeks of CBT. Fifty healthy controls (HCs) were also scanned twice at matched intervals. We constructed individual brain white matter connectome and performed a graph-theoretical network analysis to investigate the effects of CBT on whole-brain structural topology. We observed significant group-by-time interactions on the global network clustering coefficient and the nodal clustering of the left lingual gyrus, the left middle temporal gyrus, the left precuneus, and the left fusiform gyrus of 26 CBT responders in OCD patients. Further analysis revealed that these CBT responders showed prominently higher global and nodal clustering compared to HCs at baseline and reduced to normal levels after CBT. Such significant changes in the nodal clustering of the left lingual gyrus were also found in 8 CBT non-responders. The pre-to-post decreases in nodal clustering of the left lingual gyrus and the left fusiform gyrus positively correlated with the improvements in obsessive-compulsive symptoms in the CBT-responding patients. These findings indicated that the network segregation of the whole-brain white matter network in OCD patients was abnormally higher and might recover to normal after CBT, which provides mechanistic insights into the CBT response in OCD and potential imaging biomarkers for clinical practice.

The erring brain: Error-related negativity as an endophenotype for OCD-A review and meta-analysis

Obsessive-compulsive disorder (OCD) is a complex and heterogeneous disorder that is associated with high personal and societal costs. Feelings of doubt, worry, and repetitive behavior, key symptoms of OCD, have been linked to hyperactive error signals in the brain. The error-related negativity (ERN) represents a validated marker of error processing in the ERP. Increased ERN amplitudes in OCD have been reported very robustly over the last 20 years. This article integrates results from 38 studies analyzing the ERN in OCD, using a quantitative meta-analysis. Meta-regressions were used to examine potential moderators such as task type, symptom severity, age, and sample size. The meta-analysis reveals a robust increase of ERN in OCD patients compared to healthy participants in response-conflict tasks (SMD -0.55) that is not modulated by symptom severity and age. No increase in ERN in OCD was observed in tasks that do not induce response conflict (SMD -0.10). In addition to the meta-analysis, the current article reviews evidence supporting that increased ERN amplitudes in OCD fulfill central criteria for an endophenotype. Further, the specificity of increased ERN amplitudes for OCD and its suitability as a potential transdiagnostic endophenotype is discussed. Finally, the clinical utility and clinical applications are examined. Overall, the evidence that increased ERN amplitudes represent a promising endophenotype indicating vulnerability for OCD is compelling. Furthermore, alterations in ERN are not limited to OCD and may constitute a transdiagnostic endophenotype. Altered neural error signals might serve as a diagnostic or predictive marker and represent a promising target for interventions.

Evidence for trial-by-trial dynamic adjustment of task control in unmedicated adults with OCD

According to the conflict monitoring theory, executive control requires two separable processes: conflict-monitoring and conflict-resolution. Deficits in executive control have been observed in adults with obsessive-compulsive disorder (OCD). However, it is not yet clear whether these deficits can be attributed to deficits in conflict-monitoring, in conflict-resolution, or in both. We examined this question by administrating the Simon task to 67 unmedicated adults with OCD and 67 matched controls. The interference effect (incongruent minus congruent) was used to measure conflict-resolution. Trial-by-trial dynamic adaptation (i.e., the Gratton effect), which is indicated by smaller interference effect after conflict-laden trials compared to after non-conflict-laden trials, was used to measure conflict-monitoring. A similar interference effect was found in both the OCD and HC groups with no significant between group differences. Following incongruent trials, the interference effect became smaller for the control group as expected, but was completely eliminated for the OCD group. These data add to the accumulating evidence indicating that conflict-resolution is not globally deficient in unmedicated OCD patients and provide direct evidence that conflict-monitoring is heightened in OCD patients. Our results challenge the assumption of cognitive inflexibility in OCD and highlight the importance of studying unmedicated subjects when investigating executive control.

"Fake it till You Make it"! Contaminating Rubber Hands ("Multisensory Stimulation Therapy") to Treat Obsessive-Compulsive Disorder

Obsessive-compulsive disorder (OCD) is a deeply enigmatic psychiatric condition associated with immense suffering worldwide. Efficacious therapies for OCD, like exposure and response prevention (ERP), are sometimes poorly tolerated by patients. As many as 25% of patients refuse to initiate ERP mainly because they are too anxious to follow exposure procedures. Accordingly, we proposed a simple and tolerable (immersive yet indirect) low-cost technique for treating OCD that we call “multisensory stimulation therapy.” This method involves contaminating a rubber hand during the so-called “rubber hand illusion” (RHI) in which tactile sensations may be perceived as arising from a fake hand. Notably, Jalal et al. (2015) showed that such fake hand contamination during the RHI provokes powerful disgust reactions in healthy volunteers. In the current study, we explored the therapeutic potential of this novel approach. OCD patients (n = 29) watched as their hidden real hand was being stroked together with a visible fake hand; either synchronously (inducing the RHI; i.e., the experimental condition; n = 16) or asynchronously (i.e., the control condition; n = 13). After 5 min of tactile stimulation, the rubber hand was contaminated with fake feces, simulating conventional exposure therapy. Intriguingly, results suggested sensory assimilation of contamination sensations into the body image via the RHI: patients undergoing synchronous stimulation did not report greater contamination sensations when the fake hand was initially contaminated relative to asynchronous stroking. But contrary to expectations, they did so after the rubber hand had been contaminated for 5 min, as assessed via disgust facial expressions (a secondary outcome) and in vivo exposure (upon discontinuing the illusion). Further, to our surprise, synchronous and asynchronous stroking induced an equally vivid and fast-emerging illusion, which helps explain why both conditions initially (5 min after initiating tactile stimulation) provoked contamination reactions of equal magnitude. This study is the first to suggest heightened malleability of body image in OCD. Importantly, it may pave the way for a tolerable technique for the treatment of OCD—highly suitable for poorly resourced and emergency settings, including low-income and developing countries with minimal access to high-tech solutions like virtual reality.

Searchlight classification based on Amplitude of Low Frequency Fluctuation and functional connectivity in individuals with obsessive-compulsive symptoms

INTRODUCTION

Investigating obsessive-compulsive symptoms in subclinical populations provides a useful framework for understanding the early development of obsessive-compulsive spectrum disorders. The present study aimed to apply searchlight classification analysis on resting-state functional magnetic resonance imaging data to identify potential brain markers in subclinical individuals with obsessive-compulsive symptoms.

METHODS

In this observational study, 40 college students with high obsessive-compulsive symptom scores and 40 with low obsessive-compulsive symptom scores were recruited from universities in China. We conducted searchlight classification and comparison analysis between the two groups based on Amplitude of Low Frequency Fluctuation (ALFF), fraction ALFF (fALFF) and resting-state functional connectivity using searchlight classification.

RESULTS

We found that the highest accuracy rate in differentiating between the two groups was 85.00%. Significant discriminating features included the ALFF of the left medial superior frontal gyrus and the functional connectivity between the right thalamus and the bilateral medial superior frontal gyrus, and the right putamen, as well as the functional connectivity between the left caudate and the right insula.

CONCLUSIONS

These findings highlight the specific and distinguishing brain functional abnormalities associated with obsessive-compulsive symptoms.

Visual search for verbal material in patients with obsessive-compulsive disorder

This study aimed at investigating attentional mechanisms in obsessive-compulsive disorder (OCD) by analysing how visual search processes are modulated by normal and obsession-related distracting information in OCD patients and whether these modulations differ from those observed in healthy people. OCD patients were asked to search for a target word within distractor words that could be orthographically similar to the target, semantically related to the target, semantically related to the most typical obsessions/compulsions observed in OCD patients, or unrelated to the target. Patients' performance and eye movements were compared with those of individually matched healthy controls. In controls, the distractors that were visually similar to the target mostly captured attention. Conversely, patients' attention was captured equally by all kinds of distractor words, whatever their similarity with the target, except obsession-related distractors that attracted patients' attention less than the other distractors. OCD had a major impact on the mostly subliminal mechanisms that guide attention within the search display, but had much less impact on the distractor rejection processes that take place when a distractor is fixated. Hence, visual search in OCD is characterized by abnormal subliminal, but not supraliminal, processing of obsession-related information and by an impaired ability to inhibit task-irrelevant inputs.

Explicit instructions facilitate performance of OCD participants but impair performance of non-OCD participants on a serial reaction time task

Previous studies have shown that individuals diagnosed with OCD tend to rely on explicit processing while performing implicit learning tasks. We sought to investigate whether individuals with OCD are capable of implicit learning, but would demonstrate improved performance when explicit processing strategies are enhanced. Twenty-four participants with OCD and 24 non-psychiatric control (NPC) participants performed an implicit learning task in which they responded to a single target stimulus that successively appears at one of four locations according to an underlying sequence. We manipulated the learning strategy by informing half of the participants that the target stimulus location was determined by an underlying sequence, which they should identify (intentional learning). The other half of the participants was not informed of the existence of the underlying sequence, and was expected to learn the sequence implicitly (standard learning). We predicted that OCD participants will exhibit inferior performance compared to NPC participants in the standard learning condition, and that intentional learning instructions would impair the performance of NPC participants, but enhance the performance of OCD participants. The results supported these predictions and suggest that individuals with OCD prefer controlled to automatic processing. We discuss the implications of this conclusion to our understanding of OCD.

Negative Mood and Obsessive-Compulsive Related Clinical Constructs: An Examination of Underlying Factors

Emerging evidence suggests that many of the clinical constructs used to help understand and explain obsessive-compulsive (OC) symptoms, and negative mood, may be causally interrelated. One approach to understanding this interrelatedness is a motivational systems approach. This approach suggests that rather than considering clinical constructs and negative affect as separable entities, they are all features of an integrated threat management system, and as such are highly coordinated and interdependent. The aim of the present study was to examine if clinical constructs related to OC symptoms and negative mood are best treated as separable or, alternatively, if these clinical constructs and negative mood are best seen as indicators of an underlying superordinate variable, as would be predicted by a motivational systems approach. A sample of 370 student participants completed measures of mood and the clinical constructs of inflated responsibility, intolerance of uncertainty, not just right experiences, and checking stop rules. An exploratory factor analysis suggested two plausible factor structures, one where all construct items and negative mood items loaded onto one underlying superordinate variable, and a second structure comprising of five factors, where each item loaded onto a factor representative of what the item was originally intended to measure. A confirmatory factor analysis showed that the five factor model was preferential to the one factor model, suggesting the four constructs and negative mood are best conceptualized as separate variables. Given the predictions of a motivational systems approach were not supported in the current study, other possible explanations for the causal interrelatedness between clinical constructs and negative mood are discussed.

How can I know what I'm feeling? Obsessive-compulsive tendencies and induced doubt are related to reduced access to emotional states

BACKGROUND AND OBJECTIVE

People's feelings are not always accessible to them, and this might be especially the case for some individuals and in some situations. Based on our model of obsessive-compulsive disorder, we predicted that obsessive-compulsive (OC) tendencies and situationally induced doubt would be associated with decreased access to one's own emotions.

METHODS

In the first two studies we examined the relationships between OC tendencies and performance on the Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT). In Study 3 we undermined participants' confidence in their ability to accurately assess their own emotions and assessed the effect of this manipulation on MSCEIT performance.

RESULTS

As predicted, OC tendencies were associated with lower scores on the Experiential area of the MSCEIT, which relies on access to experienced emotions, but not on the Strategic area, which relies on semantic knowledge about emotions. Similarly, undermining participants' confidence in their own emotions reduced their scores on the Experiential, but not on the Strategic area of the MSCEIT.

LIMITATIONS

The findings should be replicated with a clinical OCD population and with other measures of emotional experience.

CONCLUSION

These studies suggest that impaired access to emotional states may be caused by doubting those states, that it characterizes people with high OC tendencies, and that it might be a manifestation of a more general difficulty in accessing internal states.

Things happen: Individuals with high obsessive-compulsive tendencies omit agency in their spoken language

The study examined the prediction that obsessive-compulsive tendencies are related to an attenuated sense of agency (SoA). As most explicit agency judgments are likely to reflect also motivation for and expectation of control, we examined agency in sentence production. Reduced agency can be expressed linguistically by omitting the agent or by using grammatical framings that detach the event from the entity that caused it. We examined the use of agentic language of participants with high vs. low scores on a measure of obsessive-compulsive (OC) symptoms, using structured linguistic tasks in which sentences are elicited in a conversation-like setting. As predicted, high OC individuals produced significantly more non-agentic sentences than low OC individuals, using various linguistic strategies. The results suggest that OC tendencies are related to attenuated SoA. We discuss the implications of these findings for explicating the SoA in OCD and the potential contribution of language analysis for understanding psychopathology.

Perseveration causes automatization of checking behavior in obsessive-compulsive disorder

Repeated checking leads to reductions in meta-memory (i.e., memory confidence, vividness and detail), and automatization of checking behavior (Dek, van den Hout, Giele, & Engelhard, 2014, 2015). Dek et al. (2014) suggested that this is caused by increased familiarity with the checked stimuli. They predicted that defamiliarization of checking by modifying the perceptual characteristics of stimuli would cause de-automatization and attenuate the negative meta-memory effects of re-checking. However, their results were inconclusive. The present study investigated whether repeated checking leads to automatization of checking behavior, and if defamiliarization indeed leads to de-automatization and attenuation of meta-memory effects in patients with OCD and healthy controls. Participants performed a checking task, in which they activated, deactivated and checked threat-irrelevant stimuli. During a pre- and post-test checking trial, check duration was recorded and a reaction time task was simultaneously administered as dual-task to assess automatization. After the pre- and post-test checking trial, meta-memory was rated. Results showed that relevant checking led to automatization of checking behavior on the RT measure, and negative meta-memory effects for patients and controls. Defamiliarization led to de-automatization measured with the RT task, but did not attenuate the negative meta-memory effects of repeated checking. Clinical implications are discussed.

Always on guard: test of high vs. low control conditions in obsessive-compulsive disorder patients

Obsessive-compulsive disorder (OCD) is a relatively common psychiatric disorder characterized by recurrent obsessive thoughts and/or compulsive behaviors. It has been shown that OCD patients suffer from deficits in executive control. During Stroop task performance, it was found that cognitive control in healthy participants adjusts adaptively - control is reduced when conflict is less likely. Twenty-four individuals meeting criteria for OCD and 27 controls carried out two blocks of a Stroop task; one with high control (a third of the trials were neutral) and one with low control (75% of the trials were neutral). In the healthy control group, results replicated previous findings showing increased interference and decreased facilitation in the low control condition compared to the high control condition. OCD participants, on the other hand, showed no difference in results between the two blocks. Moreover, in the high control condition, interference was larger and facilitation was smaller compared to healthy controls, indicating less efficient executive control for both the informational and task conflict. We concluded that healthy controls adjust the level of control to changing circumstances whereas OCD patients have difficulties to adaptively make such adjustments. Implications for this novel evidence of deficient executive control of flexibility in OCD patients are discussed.

The relationship between sensory processing, childhood rituals and obsessive-compulsive symptoms

BACKGROUND AND OBJECTIVES

Studies of Obsessive-Compulsive Disorder (OCD) and research in occupational therapy suggest a link between sensory hypersensitivity and excessive use of rituals. The present research constitutes an initial attempt to examine this potential link.

METHODS

In Study 1, parents of 4-6-year old children (N = 61) completed the Childhood Routine Inventory, the Sensory Profile and the Screen for Child Anxiety Related Emotional Disorders. In Study 2 we administered an adapted version of the sensory profile to an internet sample of adult participants (N = 314) together with the Obsessive-Compulsive Inventory-Revised, the anxiety subscale of the International Personality Item Pool - NEO and items measuring participants' recollection of their childhood oral and tactile hypersensitivity.

RESULTS

Strong reactions to everyday sensory events were highly correlated with childhood ritualism, even after controlling for anxiety. In the adult sample, current and recollected oral and tactile hypersensitivity were significantly related to OCD symptoms.

LIMITATIONS

In Study 1, children's sensory sensitivity was not tested directly, but rather through parental report. The scale was developed ad hoc based on face validity and relationship with ritualism. The studies were cross-sectional in design. Study 2 partially relied on recollection of childhood behavior.

CONCLUSIONS

The results suggest a strong relationship between sensory sensitivity, childhood ritualism and adult OCD symptoms. Oral and tactile hypersensitivity in childhood may be one pathway to adult OCD.

Obsessive-compulsive tendencies and undermined confidence are related to reliance on proxies for internal states in a false feedback paradigm

BACKGROUND AND OBJECTIVES

We have previously hypothesized that obsessive-compulsive (OC) tendencies are associated with a general lack of subjective conviction regarding internal states, which leads to compensatory seeking of and reliance on more discernible substitutes (proxies) for these states (Lazarov, A., Dar, R., Oded, Y., & Liberman, N. (2010). Behaviour Research and Therapy, 48, 516-523). This article presents two studies designed to provide further support to this hypothesis by using false biofeedback as a proxy for internal states.

METHODS

In Study 1 we presented high and low OC participants with pre-programmed false feedback showing either increasing or decreasing levels of muscle tension. In Study 2 we presented similar false feedback on level of relaxation to non-selected participants, half of which received instructions that undermined their confidence in their ability to assess their own level of relaxation.

RESULTS

In Study 1, high OC participants were more affected by false biofeedback when judging their own level of muscle tension than were low OC participants. In Study 2, undermined confidence participants were more affected by false biofeedback when judging their own level of relaxation as compared to control participants.

LIMITATIONS

Our findings are based on a non-clinical, highly functioning, largely female student sample and their generalization to OCD requires replication with a sample of OCD patients.

CONCLUSIONS

These results provide converging evidence for our hypothesis by replicating and extending our previous findings. We discuss the implication of our hypothesis for the understanding and treatment of OCD and outline directions for future research.

Trial-by-Trial Adjustments of Cognitive Control Following Errors and Response Conflict are Altered in Pediatric Obsessive Compulsive Disorder

BACKGROUND

Impairments of cognitive control have been theorized to drive the repetitive thoughts and behaviors of obsessive compulsive disorder (OCD) from early in the course of illness. However, it remains unclear whether altered trial-by-trial adjustments of cognitive control characterize young patients. To test this hypothesis, we determined whether trial-by-trial adjustments of cognitive control are altered in children with OCD, relative to healthy controls.

METHODS

Forty-eight patients with pediatric OCD and 48 healthy youth performed the Multi-Source Interference Task. Two types of trial-by-trial adjustments of cognitive control were examined: post-error slowing (i.e., slower responses after errors than after correct trials) and post-conflict adaptation (i.e., faster responses in high-conflict incongruent trials that are preceded by other high-conflict incongruent trials, relative to low-conflict congruent trials).

RESULTS

While healthy youth exhibited both post-error slowing and post-conflict adaptation, patients with pediatric OCD failed to exhibit either of these effects. Further analyses revealed that patients with low symptom severity showed a reversal of the post-conflict adaptation effect, whereas patients with high symptom severity did not show any post-conflict adaptation.

CONCLUSION

Two types of trial-by-trial adjustments of cognitive control are altered in pediatric OCD. These abnormalities may serve as early markers of the illness.

Cognitive rigidity in unipolar depression and obsessive compulsive disorder: examination of task switching, Stroop, working memory updating and post-conflict adaptation

Obsessive compulsive disorder (OCD) and depressive rumination are both characterized by cognitive rigidity. We examined the performance of 17 patients (9 suffering from unipolar depression [UD] without OCD, and 8 suffering from OCD without UD), and 17 control participants matched on age, gender, language and education, on a battery covering the four main executive functions. Results indicated that, across both disorders, patients required more trials to adjust to single-task conditions after experiencing task switching, reflecting slow disengagement from switching mode, and showed abnormal post-conflict adaptation of processing mode following high conflict Stroop trials in comparison to controls. Rumination, which was elevated in UD and not in OCD, was associated with poor working memory updating and less task preparation. The results show that OCD and UD are associated with similar cognitive rigidity in the presently tested paradigms.

Obsessive-compulsive disorder: diagnostic and treatment issues

This article reviews current issues in the diagnosis and treatment of obsessive-compulsive disorder (OCD). The introduction of the selective serotonin reuptake inhibitors and of cognitive-behavioral therapy were significant advances for treating OCD. Nevertheless, there is a need to improve awareness of OCD and its management, and to develop novel approaches to treatment-refractory patients. Although the diagnostic criteria for OCD have remained unchanged for some time, there are several areas where potential modification may be useful. There is a growing evidence base on OCD symptom dimensions and subtyping, and it is timely to consider incorporating some of these emerging data into diagnostic classification systems.

Uncertainty about perception and dissociation after compulsive-like staring: time course of effects

Repeated and compulsive-like checking reduces confidence in memory for the last check. Obsessive-compulsive (OC) patients are not only uncertain about memory, but may also be uncertain about perception, while this perceptual uncertainty may be associated with prolonged visual fixation on the object of uncertainty. It was reported earlier that, among healthy participants, prolonged staring at light bulbs or gas rings induces OC-like uncertainty about perception and feelings of dissociation [van den Hout, M. A., Engelhard, I. M., de Boer, C., du Bois, A., & Dek, E. (2008). Perseverative and compulsive-like staring causes uncertainty about perception. Behaviour Research and Therapy, 46, 1300-1304]. In that study, staring continued for 10min. For patients, however, staring intervals seem to be considerably shorter. To test the clinical credibility of the paradigm as a model of the maintenance of OC perceptual uncertainty, we investigated whether the effects of staring materialize long before 10min. Five groups of 16 undergraduates participated: one group did not stare at a gas stove while the others stared for 7.5, 15, 30 or 300s. In the absence of staring, no pre-to-post increase in dissociation/uncertainty was reported, but after staring it was. The larger part of the observed dissociation/uncertainty after 5min had occurred within 30s, and around 50% of this maximal increase was reported between 7.5 and 15s. Thus, even relatively short intervals of staring induce uncertainty about perception and dissociative experiences. Perseverative looking at objects may be a counter-productive OC strategy, which increases uncertainty about perception and may serve to maintain the disorder.