Implicit learning, thought-focused attention and obsessive-compulsive disorder: a replication and extension

Individual differences in probabilistic learning and updating predictive representations in individuals with obsessive-compulsive tendencies

BACKGROUND

Obsessive-compulsive (OC) tendencies involve intrusive thoughts and rigid, repetitive behaviours that also manifest at the subclinical level in the general population. The neurocognitive factors driving the development and persistence of the excessive presence of these tendencies remain highly elusive, though emerging theories emphasize the role of implicit information processing. Despite various empirical studies on distinct neurocognitive processes, the incidental retrieval of environmental structures in dynamic and noisy environments, such as probabilistic learning, has received relatively little attention.

METHODS

In this study, we aimed to unravel potential individual differences in implicit probabilistic learning and the updating of predictive representations related to OC tendencies in a non-clinical population. We conducted two independent online experiments (NStudy1 = 164, NStudy2 = 256) with university students. Probabilistic learning was assessed using an implicit visuomotor probabilistic learning task, involving sequences with second-order non-adjacent dependencies.

RESULTS

Our findings revealed that implicit probabilistic learning remained remarkably robust among OC tendencies within a non-clinical population. Furthermore, the results highlighted effective updating capabilities of predictive representations, which were not influenced by OC tendencies.

CONCLUSIONS

These results offer new insights into individual differences in probabilistic learning and updating in relation to OC tendencies, contributing to theoretical, methodological, and practical approaches for understanding the maladaptive behavioural manifestations of OC disorder and subclinical tendencies.

Decision-making using the Iowa gambling test in unaffected first-degree relatives of obsessive-compulsive disorder: Comparison with healthy controls and patients with obsessive-compulsive disorder

Decision-making has been suggested as an endophenotype candidate for obsessive-compulsive disorder (OCD). However, few studies have examined whether decision-making under ambiguity is an endophenotype of OCD. This study aimed to investigate decision-making under ambiguity, as assessed by the Iowa Gambling Task (IGT), in patients with OCD and unaffected first-degree relatives (UFDR). Forty-seven non-medicated, non-co-morbid patients with OCD, 30 UFDR, and 47 healthy controls (HC) were compared in terms of decision-making using the IGT. The correlation between obsessive-compulsive symptoms and IGT performance was also investigated. Patients with OCD and UFDR performed worse than HC on the IGT. No correlation was found between obsessive-compulsive symptoms and IGT performance. A deficit in decision-making under ambiguity may be a trait and an endophenotype candidate for OCD.

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

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

Adaptive behavior and psychiatric symptoms in university students with ASD: One-year longitudinal study

In recent years, more young adults with ASD are attending post-secondary education, and several support programs have been proposed for this population. However, research regarding the long-term effects of university enrollment on outcomes among students with ASD is scarce. This study examined adaptive behavior and psychiatric symptoms during the first semester of two consecutive academic years (T1, T2) among 39 students with ASD, 29 students without ASD and high levels of social anxiety symptoms (High SA), and 32 students without ASD and low levels of SA symptoms (Low SA). Students with ASD participated in a university support program and resided with a peer mentor student without ASD, which encouraged social interaction. At T1, students with ASD reported lower levels of adaptive behavior and higher levels of social anxiety and obsessive-compulsive symptoms compared to the other groups. However, at follow-up (T2), significantly higher conceptual adaptive skill levels (specifically communication skills) and significantly lower depression symptom levels from T1 were reported only among students with ASD. The levels of social anxiety and obsessive-compulsive symptoms at T1 were negatively associated with adaptive functioning a year later (T2). Implications regarding adults with ASD attending university are discussed.

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.

Cognitive impairment in hoarding disorder: a systematic review

OBJECTIVE

In the present study, we aimed to perform a systematic review evaluating the cognitive performance of patients with hoarding disorder (HD) compared with controls. We hypothesized that HD patients would present greater cognitive impairment than controls.

METHODS

A systematic search of the literature using the electronic databases MEDLINE, SCOPUS, and LILACS was conducted on May 2020, with no date limit. The search terms were "hoarding disorder," "cognition," "neuropsychology," "cognitive impairment," and "cognitive deficit." We included original studies assessing cognitive functioning in patients with HD.

RESULTS

We retrieved 197 studies initially. Of those, 22 studies were included in the present study. We evaluated 1757 patients who were 41 to 72 years old. All selected studies comprised case-control studies and presented fair quality. Contrary to our hypothesis, HD patients showed impairment only in categorization skills in comparison with controls, particularly at confidence to complete categorization tasks. Regarding attention, episodic memory, working memory, information-processing speed, planning, decision-making, inhibitory control, mental flexibility, language, and visuospatial ability, HD patients did not show impairment when compared with controls. There is a paucity of studies on social cognition in HD patients, although they may show deficits. The impact of emotion in cognition is also understudied in HD patients.

CONCLUSION

Except for categorization skills, the cognitive performance in HD patients does not seem to be impaired when compared with that in controls. Further work is needed to explore social cognition and the impact of emotion in cognitive performance in HD patients.

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.

Distinct Aspects of Decision Making in Obsessive-Compulsive Disorder: Application of Unconscious Thought Theory

Individuals with obsessive-compulsive disorder (OCD) rely on "explicit learning" strategies in decision making. It is suggested that periods of brief distraction (in healthy individuals) result in better decisions in complex situations. It can be hypothesized that periods of unconscious thought would not lead to better decisions due to impairment of implicit learning in OCD. A total of 121 OCD patients and 120 healthy participants were presented with a task in which they had to choose between four apartments with multiple attributes. Participants were randomly assigned to one of three conditions: making a decision immediately after being presented with options (immediate), after thinking carefully for 2 minutes (conscious thought [CT]), or after being distracted for 2 minutes (unconscious thought [UT]). Individuals with OCD performed worse than healthy controls in UT condition, although they did better in CT condition. Our study supports the idea of dysfunction in implicit processing and overreliance on explicit processes in OCD.

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.

The Neural Correlates of Probabilistic Classification Learning in Obsessive-Compulsive Disorder: A Pilot Study

Individuals suffering from obsessive-compulsive disorder (OCD) have been found to show deficits in implicitly learning probabilistic associations between events. Neuroimaging studies have associated these implicit learning deficits in OCD individuals with aberrant activation of the striatal system. Recent behavioral studies have highlighted that probabilistic classification learning (PCL) deficits in OCD individuals only occur in a disorder-specific context, while PCL remains intact in a neutral context. The neural correlates of implicit learning in an OCD-specific context, however, have not yet been investigated. Using functional magnetic resonance imaging during a neutral (prediction of weather) and an OCD-specific variant (prediction of a virus epidemic) of a PCL paradigm, we assessed brain activity associated with implicit learning processes in 10 participants with OCD and 10 matched healthy controls. Regions of interest (ROIs) were the striatum and the medial temporal lobe. ROI analyses revealed a significantly higher activity in the bilateral putamen and the left hippocampus of OCD participants as compared to healthy controls during both PCL tasks. The group differences could partly be subsumed under a group × task interaction effect with OCD participants showing a significantly higher activity than healthy controls in the left putamen and the left hippocampus in the OCD-specific task variant only. These results suggest a compensation of aberrant striatal activity by an augmented engagement of the explicit memory system particularly in a disorder-relevant context in OCD participants.

The impact of attentional and emotional demands on memory performance in obsessive-compulsive disorder

Lower performance on memory tests in obsessive-compulsive disorder (OCD) has been repeatedly observed. However, the origins of these performance deficits are not sufficiently explained. In this study we tested if OCD-related extensive focus of attention on thoughts (heightened self-consciousness) could be an explanatory mechanism for lower memory performance. Heightened situational self-consciousness was manipulated by instructing participants to either monitor neutral thoughts or to monitor OCD-related thoughts. We included a Behavioral Avoidance Task based on individual obsessions and compulsions to induce OCD-related thoughts. Participants were asked to perform these monitoring tasks in parallel to a taxing verbal memory task, resulting in learning under divided attention. The two conditions of learning under divided attention were compared to a single-task condition. Twenty-four participants with OCD and 24 healthy controls took part in these three learning conditions. The results indicate that in both groups memory performance deteriorated in the two conditions with divided attention compared to the single task condition. In the OCD-related thought monitoring condition (OTM) self-consciousness and Behavioral Avoidance Task-induced stress and fear were particularly increased and memory performance further deteriorated in the OCD group. This finding highlights an important and underestimated mechanism (personal involvement) which might serve to better understand lower memory performance in OCD.

Does cognitive self-consciousness link older adults' cognitive functioning to obsessive-compulsive symptoms?

To elucidate how obsessional symptoms might develop or intensify in late-life, we tested a risk model. We posited that cognitive self-consciousness (CSC), a tendency to be aware of and monitor thinking, would increase reactivity to aging-related cognitive changes and mediate the relationship between cognitive functioning and obsessive-compulsive disorder (OCD) symptoms. Older adults (Mage = 76.7 years) completed the Dementia Rating Scale-2 (DRS-2), a CSC measure, and an OCD symptom measure up to four times over 18 months. A model that included DRS-2 age and education adjusted total score as the indicator of cognitive functioning fit the data well, and CSC score change mediated the relationship between initial cognitive functioning and changes in OCD symptoms. In tests of a model that included DRS-2 Initiation/Perseveration (I/P) and Conceptualization subscale scores, the model again fit the data well. Conceptualization scores, but not I/P scores, were related to later OCD symptoms, and change in CSC scores again mediated the relationship. Lower scores on initial cognitive functioning measures predicted increases in CSC scores over time, which in turn predicted increases in OCD symptoms over the 18 months of the study. Implications for understanding late-life obsessional problems are discussed.

Probing Implicit Learning in Obsessive-Compulsive Disorder: Moderating Role of Medication on the Weather Prediction Task

Deficits in implicit learning, a process by which knowledge is acquired accretively through practice independent of conscious awareness, have been implicated in Obsessive-Compulsive Disorder (OCD). The weather-prediction task (WPT) was used to assess implicit learning in 26 unmedicated patients with OCD and 23 healthy controls. An additional analysis compared these two groups with 25 medicated patients with OCD. In the comparison of unmedicated patients with healthy controls there was a subtle but statistically significant group-by-block interaction. Patients with OCD showed slower improvement in performance during the middle phase of learning. In a three-group comparison, there was no main effect of group; in post-hoc tests, medicated patients with OCD differed from unmedicated patients and were not different from healthy controls. Unmedicated patients with OCD have a subtle deficit in implicit learning in the WPT. This may be mitigated by pharmacotherapy, although prospective studies would be required to confirm this conclusion.

Neural correlates of processing harmonic expectancy violations in children and adolescents with OCD

It has been suggested that patients with obsessive–compulsive disorder (OCD) exhibit enhanced awareness of embedded stimulus patterns as well as enhanced allocation of attention towards unexpected stimuli. Our study aimed at investigating these OCD characteristics by running the harmonic expectancy violation paradigm in 21 boys with OCD and 29 healthy controls matched for age, gender and IQ during a functional magnetic resonance imaging (fMRI) scan. Each trial consisted of a chord sequence in which the first four chords induced a strong expectancy for a harmonic chord at the next position. In 70% of the trials the fifth chord fulfilled this expectancy (harmonic condition), while in 30% the expectancy was violated (disharmonic condition). Overall, the harmonic condition elicited blood-oxygen-level dependent (BOLD) activation in the auditory cortex, while during the disharmonic condition the precuneus, the auditory cortex, the medial frontal gyrus, the premotor cortex, the lingual gyrus, the inferior frontal gyrus and the superior frontal gyrus were activated. In a cluster extending from the right superior temporal gyrus to the inferior frontal gyrus, boys with OCD exhibited increased activation compared to healthy controls in the harmonic condition and decreased activation in the disharmonic condition. Our findings might indicate that patients with OCD are excessively engaged in processing the implicit structure embedded in music stimuli, but they speak against the suggestion that OCD is associated with a misallocation of attention towards the processing of unexpected stimuli.

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We ran the harmonic expectancy violations in boys with OCD and controls during fMRI.

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We examined processing of embedded stimulus pattern and unexpected stimuli.

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We found increased activation in superior temporal/inferior frontal gyrus in OCD.

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Boys with OCD excessively processed the implicit structure of music stimuli.

Neurocognitive performance in unmedicated patients with hoarding disorder

OBJECTIVE

Hoarding disorder (HD) is an often incapacitating psychiatric illness associated with a wide range of neurocognitive abnormalities. Some prior neuropsychological studies have found executive dysfunction in HD, but no clear pattern has emerged. One potential reason for discrepant results in previous studies might be the inclusion of patients on psychotropic and other medications that can affect neurocognitive performance. Therefore, we examined neurocognitive functioning in medication-free HD patients. We also added a novel investigation of implicit learning, which has been found to be abnormal in obsessive-compulsive disorder (OCD) and related disorders.

METHOD

Twenty-six participants meeting the Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM-5; American Psychiatric Association, 2013) diagnostic criteria for HD and 23 normal controls were administered a battery of neuropsychological tests and symptom rating scales. All participants were free of psychotropic medications for at least 6 weeks prior to the study.

RESULTS

HD participants showed no significant differences from normal controls on measures of verbal memory, attention, or executive functioning, including response inhibition, planning, organization, and decision making. However, HD participants demonstrated a trend toward less implicit learning and greater use of explicit learning strategies during perceptual categorization compared to normal controls. HD participants who used an implicit strategy performed significantly worse than controls who used an implicit strategy. Hoarding symptom severity was not associated with neurocognitive performance.

CONCLUSIONS

HD patients may have a tendency to use explicit rather than implicit learning strategies for perceptual categorization but perform as well as normal controls on many other neurocognitive measures. Future studies should assess unmedicated participants and examine test strategies, not just outcomes.

Does "thinking about thinking" interfere with memory? An experimental memory study in obsessive-compulsive disorder

Neuropsychological assessments of participants with obsessive-compulsive disorder (OCD) indicate impaired verbal memory if to be remembered material has to be organized. People with OCD also tend to focus their attention on their thoughts (heightened cognitive self-consciousness). We tested the hypothesis that cognitive self-consciousness causes verbal memory deficits by provoking a division of attention between study task and thoughts. Thirty-six participants with OCD, 36 matched healthy controls and 36 participants with major depressive disorder (MDD) learned under proactive interference in three study conditions: single-task condition, condition with heightened cognitive self-consciousness and condition with an external secondary task. Memory was impaired in the cognitive self-consciousness condition compared to both other conditions. Independent of condition, participants with OCD showed a reduced memory performance compared to healthy controls, but did not differ from participants with MDD. Our results are in line with the hypothesis that cognitive self-consciousness causes memory impairment.

The neurobiological link between OCD and ADHD

Obsessive compulsive disorder (OCD) and attention deficit hyperactivity disorder (ADHD) are two of the most common neuropsychiatric diseases in paediatric populations. The high comorbidity of ADHD and OCD with each other, especially of ADHD in paediatric OCD, is well described. OCD and ADHD often follow a chronic course with persistent rates of at least 40–50 %. Family studies showed high heritability in ADHD and OCD, and some genetic findings showed similar variants for both disorders of the same pathogenetic mechanisms, whereas other genetic findings may differentiate between ADHD and OCD. Neuropsychological and neuroimaging studies suggest that partly similar executive functions are affected in both disorders. The deficits in the corresponding brain networks may be responsible for the perseverative, compulsive symptoms in OCD but also for the disinhibited and impulsive symptoms characterizing ADHD. This article reviews the current literature of neuroimaging, neurochemical circuitry, neuropsychological and genetic findings considering similarities as well as differences between OCD and ADHD.

Imminent danger? Probabilistic classification learning of threat-related information in obsessive-compulsive disorder

A tendency to overestimate threat has been shown in individuals with OCD. We tested the hypothesis that this bias in judgment is related to difficulties in learning probabilistic associations between events. Thirty participants with OCD and 30 matched healthy controls completed a learning experiment involving 2 variants of a probabilistic classification learning task. In the neutral weather-prediction task, rainy and sunny weather had to be predicted. In the emotional task danger of an epidemic from virus infection had to be predicted (epidemic-prediction task). Participants with OCD were as able as controls to improve their prediction of neutral events across learning trials but scored significantly below healthy controls on the epidemic-prediction task. Lower performance on the emotional task variant was significantly related to a heightened tendency to overestimate threat. Biased information processing in OCD might thus hamper corrective experiences regarding the probability of threatening events.

Involuntary social cue integration in patients with obsessive compulsive disorder

OBJECTIVE

Patients with obsessive compulsive disorder (OCD) have inferior social functioning compared to healthy controls, but the exact nature of these social deficits, and the underpinning mechanisms, are unknown. We sought to investigate social functioning in patients with OCD by measuring their involuntary/spontaneous processing of social cues using a specifically designed test, which might reveal deficits in these patients that explicit voluntary tasks do not detect.

METHODS

The sample of the study consisted of an OCD group (n = 25) and a control group (n = 26). Both groups performed an adaptation of the Social Distance Judgment Task (SDJT; Jellema et al., 2009), in which participants have to judge the geometrical distance between two human cartoon figures presented on a computer screen. Head/gaze direction and body direction were manipulated to be either compatible, i.e. both directed to the left or to the right (Compatible condition) or incompatible, i.e. body directed toward the observer (frontal view) and head/gaze directed to the left or right (Incompatible condition).

RESULTS

In the Compatible condition, controls nor OCD patients were influenced by the social cues in their judgments of the geometrical distances. However, in the Incompatible condition, where the attentional cue was more conspicuous, both groups were influenced by the cues, but the controls to a significantly larger extent than the OCD patients.

CONCLUSIONS

This study showed that patients with OCD are less likely, compared to controls, to automatically/spontaneously integrate the other's direction of attention into their visual percept. This may have resulted in their judgments of the geometrical distances between the agents to be more accurate than those of controls. The suggested impairment in automatically integrating social cues may have important repercussions for the social functioning of OCD patients.

An Investigation of Executive Functioning, Attention and Working Memory in Compulsive Hoarding

Background: Compulsive Hoarding involves the acquisition of, and failure to discard, a large number of possessions that appear to be useless or of limited value, cluttered living spaces and significant distress or impairment in functioning (Frost and Hartl, 1996). The problem is multifaceted and appears best explained by a cognitive-behavioural framework. Aims: This study set out to test one aspect of Frost and Hartl's (1996) cognitive-behavioural model of compulsive hoarding by investigating theorized cognitive deficits in executive functioning, such as working memory and attention. Method: 24 participants with compulsive hoarding were tested on the Digit Span, Spatial Span and the Wisconsin Card Sorting Tests (WCST). Results: On the WCST, the hoarding group had a significantly higher number of perseveration errors (t = 1.67, p = .005) and significantly lower numbers of categories completed (t = −2.47, p = .001) than test norms. Only “failure to maintain set” was significantly correlated with hoarding severity (r = .435, p < .05). Conclusions: These findings lend support to the theory that people who compulsively hoard have executive dysfunction, which impacts on their ability to process information. Deficits relate to difficulties in forming effective strategies, inadequate feedback response, problems in concept formation, and impulsivity. Difficulties in sustained attention also appeared to be a factor in hoarding severity. These findings are important in directing more targeted clinical interventions.

Underlying mechanisms of verbal memory deficits in obsessive-compulsive disorder and major depression--the role of cognitive self-consciousness

BACKGROUND AND OBJECTIVES

Previous studies have demonstrated that some individuals suffering from obsessive-compulsive disorder (OCD) are impaired in verbal memory performance. This study was designed to investigate the role of cognitive self-consciousness (CSC) as a putative underlying mechanism of these cognitive deficits.

METHODS

Verbal memory performance of 36 participants with OCD, 36 individuals with major depression disorder (MDD) and 36 healthy controls was assessed with the California Verbal Learning Test under three different experimental conditions: (1) single-task condition, (2) while simultaneously focusing on their thoughts (CSC condition), (3) while simultaneously focusing on external stimuli (dual-task condition).

RESULTS

Memory performance in the CSC condition and in the dual-task condition was reduced compared to single-task condition but no interaction effect was found.

LIMITATIONS

It remains unclear whether CSC and other concepts with an inward self-referential focus of attention (e.g. rumination) differ in the way they influence cognitive performance.

CONCLUSIONS

These results confirm the deteriorating influence of heightened CSC on verbal memory encoding but suggest that the effect is not specific to OCD.

Obsessive-compulsive disorder: beyond segregated cortico-striatal pathways

Obsessive-compulsive disorder (OCD) affects approximately 2-3% of the population and is characterized by recurrent intrusive thoughts (obsessions) and repetitive behaviors or mental acts (compulsions), typically performed in response to obsessions or related anxiety. In the past few decades, the prevailing models of OCD pathophysiology have focused on cortico-striatal circuitry. More recent neuroimaging evidence, however, points to critical involvement of the lateral and medial orbitofrontal cortices, the dorsal anterior cingulate cortex and amygdalo-cortical circuitry, in addition to cortico-striatal circuitry, in the pathophysiology of the disorder. In this review, we elaborate proposed features of OCD pathophysiology beyond the classic parallel cortico-striatal pathways and argue that this evidence suggests that fear extinction, in addition to behavioral inhibition, is impaired in OCD.

Cognitive functioning in compulsive hoarding

The aim of this study is to determine whether neurocognitive performance distinguishes individuals with compulsive hoarding (CH) from those with obsessive-compulsive disorder (OCD). Compared to control subjects, OCD patients and CHs scored significantly worse on the Serial Reaction Time Task suggesting disturbed implicit memory in both patient groups. On the Iowa Gambling Task, an overall learning progression difference over time was found between the CHs, OCD group, and control subjects, suggesting differences in decision-making between the groups. The groups did not differ in performance on the Stop Signal Reaction Time Task (motor inhibition). This study found evidence for impaired implicit memory in CHs, but also in OCD patients, albeit less severe. There was evidence that OCD patients learned more slowly on a decision-making task than CHs and control subjects. This latter finding provides some evidence to suggest that CH and OCD have, at least on this one measure, differing cognitive substrates.

Effects of cognitive self-consciousness on visual memory in obsessive-compulsive disorder

Previous research has documented high trait cognitive self-consciousness (CSC) in obsessive-compulsive disorder (OCD). It remains unclear whether elevated CSC levels can also explain cognitive performance deficits that have frequently been found in OCD. This study examined whether experimentally heightened CSC affects visual memory performance in OCD. OCD participants and healthy controls completed a complex figure test under three experimental conditions: simultaneously focusing on their thoughts (= CSC condition), simultaneously focusing on acoustic stimuli (= dual-task condition), and without a parallel task (= standard condition). In the OCD sample both the CSC condition and the dual-task condition reduced memory performance compared to the standard condition, whereas in controls only the dual-task condition led to reduced performance. Results indicate that raising CSC in OCD has a deteriorating effect on memory encoding that parallels the effect of a secondary task. High CSC and its effects on cognitive performance might be amenable to meta-cognitive treatment approaches.

Neurocognitive performance in children with ADHD and OCD

Attention-deficit/hyperactivity Disorder (ADHD) and obsessive-compulsive disorder (OCD) have both been linked to dysfunction in the cortico-striato-thalamo-cortical circuitry (CSTCC). However, the exact nature of neurocognitive deficits remains to be investigated in both disorders. We applied two neuropsychological tasks that tap into different functions associated with the CSTCC, namely a serial reaction time (SRT) task, developed to assess implicit sequence learning, and a delay aversion (DA) task in order to assess abnormal motivational processes. The performance data of boys with ADHD (n=20), OCD (n=20) and healthy controls (n=25), all aged 10-18 years, were compared. Subjects with ADHD less frequently chose the larger, more delayed reward compared to those with OCD and controls, while subjects with OCD showed impaired implicit learning. In contrast, the ADHD group was unimpaired in their implicit learning behavior and the OCD group was not characterized by a DA style. Within the OCD-group, severity of obsessions was associated with implicit learning deficits and impulsive symptoms with DA in the ADHD-group. This double dissociation highlights the distinct cognitive dysfunctions associated with ADHD and OCD and might possibly point to different neural abnormalities in both disorders.

Metacognitive beliefs in obsessive-compulsive patients: a comparison with healthy and schizophrenia participants

INTRODUCTION

Distorted metacognitive beliefs are increasingly considered in theoretical models of obsessive-compulsive disorder (OCD). However, so far no consensus has emerged regarding the specific metacognitive profile of OCD.

METHODS

Participants with OCD (n=55), schizophrenia (n=39), and nonclinical controls (n=49) were assessed with the Metacognitions Questionnaire (MCQ-30).

RESULTS

Except for positive beliefs about worry, both patient samples exceeded nonclinical controls on all MCQ subscales. The MCQ "need to control thoughts" and "negative beliefs about uncontrollability and danger" subscales showed strong correlations with obsessions, and scores in the former scale were elevated in hallucinators. In contrast to several prior studies, "cognitive confidence" was related neither to core OCD nor to schizophrenia symptomatology.

CONCLUSIONS

Notwithstanding large pathogenetic differences between OCD and schizophrenia, findings suggest that obsessions and hallucinations may share a common metacognitive pathway. Need to control thoughts and dysfunctional beliefs about the malleability of worries may represent critical prerequisites for the two phenomena to emerge.

Obsessive-compulsive disorder: a review of the diagnostic criteria and possible subtypes and dimensional specifiers for DSM-V

BACKGROUND

Since the publication of the DSM-IV in 1994, research on obsessive-compulsive disorder (OCD) has continued to expand. It is timely to reconsider the nosology of this disorder, assessing whether changes to diagnostic criteria as well as subtypes and specifiers may improve diagnostic validity and clinical utility.

METHODS

The existing criteria were evaluated. Key issues were identified. Electronic databases of PubMed, ScienceDirect, and PsycINFO were searched for relevant studies.

RESULTS

This review presents a number of options and preliminary recommendations to be considered for DSM-V. These include: (1) clarifying and simplifying the definition of obsessions and compulsions (criterion A); (2) possibly deleting the requirement that people recognize that their obsessions or compulsions are excessive or unreasonable (criterion B); (3) rethinking the clinical significance criterion (criterion C) and, in the interim, possibly adjusting what is considered "time-consuming" for OCD; (4) listing additional disorders to help with the differential diagnosis (criterion D); (5) rethinking the medical exclusion criterion (criterion E) and clarifying what is meant by a "general medical condition"; (6) revising the specifiers (i.e., clarifying that OCD can involve a range of insight, in addition to "poor insight," and adding "tic-related OCD"); and (7) highlighting in the DSM-V text important clinical features of OCD that are not currently mentioned in the criteria (e.g., the major symptom dimensions).

CONCLUSIONS

A number of changes to the existing diagnostic criteria for OCD are proposed. These proposed criteria may change as the DSM-V process progresses.

Should an obsessive-compulsive spectrum grouping of disorders be included in DSM-V?

The obsessive-compulsive (OC) spectrum has been discussed in the literature for two decades. Proponents of this concept propose that certain disorders characterized by repetitive thoughts and/or behaviors are related to obsessive-compulsive disorder (OCD), and suggest that such disorders be grouped together in the same category (i.e. grouping, or "chapter") in DSM. This article addresses this topic and presents options and preliminary recommendations to be considered for DSM-V. The article builds upon and extends prior reviews of this topic that were prepared for and discussed at a DSM-V Research Planning Conference on Obsessive-Compulsive Spectrum Disorders held in 2006. Our preliminary recommendation is that an OC-spectrum grouping of disorders be included in DSM-V. Furthermore, we preliminarily recommend that consideration be given to including this group of disorders within a larger supraordinate category of "Anxiety and Obsessive-Compulsive Spectrum Disorders." These preliminary recommendations must be evaluated in light of recommendations for, and constraints upon, the overall structure of DSM-V.

Metacognition and episodic memory in obsessive-compulsive disorder

Memory deficits in patients with obsessive-compulsive disorder (OCD) have been frequently reported but are not sufficiently accounted for by cognitive models of OCD. The aim of the study was to identify cognitive mechanisms that might be able to explain memory deficits in OCD. We hypothesized that a self-conscious meta-cognitive style might be responsible for reduced memory performance in OCD. Episodic verbal memory performance was assessed in 23 participants with OCD (DSM-IV criteria) and 22 matched controls. Cognitive self-consciousness was assessed with a self-report measure derived from the Meta-Cognitions Questionnaire (MCQ). Compared to controls, OCD participants showed reduced immediate and delayed recall of complex verbal material and increased self-reported levels of cognitive self-consciousness. Multiple regression analyses indicated that group differences in story recall were significantly mediated by self-reported trait cognitive self-consciousness. Results point to the deteriorating effects of a thought-focused cognitive style on effortful encoding processes in OCD.

Cognitive self-consciousness--a predictor of increased anxiety following first-time diagnosis of age-related hearing loss

This study tested prospective models of anxiety and depression following a first time diagnosis of age-related hearing loss, also known as presbycusis, which is one of the most common and disabling health problems in the world. The predictor of interest was cognitive self-consciousness (CSC; Cartwright-Hatton & Wells (1997). Beliefs about worry and intrusions: The Meta-Cognitions Questionnaire and its correlates. Journal of Anxiety Disorders, 11, 276-279.), or the tendency to closely attend to and monitor the content and process of one's own thoughts. Sixty-seven older adults were assessed at a university-based audiology clinic at three timepoints: at the time of diagnosis (T1), six (T2), and 12 months later (T3). Measures of anxiety, depression, and CSC were collected. It was hypothesized that a subset of older adults with hearing loss would report increased CSC at T2. Additionally, the interaction of CSC and anxiety and depression symptoms at T2 was expected to predict significant variance in measures of anxiety and depression at T3, even after baseline levels of distress were controlled in regression models. Finally, it was hypothesized that consistent use of a hearing aid by T3 would act as a palliative to reduce distress in response to hearing loss at T3. Results were partially consistent with hypotheses and point to a new direction in preventing anxiety and depression following a first time diagnosis of presbycusis.

Neurobiology and treatment of compulsive hoarding

Compulsive hoarding is a common and often disabling neuropsychiatric disorder. This article reviews the phenomenology, etiology, neurobiology, and treatment of compulsive hoarding. Compulsive hoarding is part of a discrete clinical syndrome that includes difficulty discarding, urges to save, clutter, excessive acquisition, indecisiveness, perfectionism, procrastination, disorganization, and avoidance. Epidemiological and taxometric studies indicate that compulsive hoarding is a separate but related obsessive-compulsive spectrum disorder that is frequently comorbid with obsessive-compulsive disorder (OCD). Compulsive hoarding is a genetically discrete, strongly heritable phenotype. Neuroimaging and neuropsychological studies indicate that compulsive hoarding is neurobiologically distinct from OCD and implicate dysfunction of the anterior cingulate cortex and other ventral and medial prefrontal cortical areas that mediate decision-making, attention, and emotional regulation. Effective treatments for compulsive hoarding include pharmacotherapy and cognitive-behavioral therapy. More research will be required to determine the etiology and pathophysiology of compulsive hoarding, and to develop better treatments for this disorder.