Publications by authors named "Reuven Dar"

The construct of sense of agency (SoA) has proven useful for understanding mechanisms underlying obsessive-compulsive disorder (OCD) phenomenology, especially in explaining the apparent dissociation in OCD between actual and perceived control over one's actions. Paradoxically, people with OCD appear to experience both diminished SoA (feeling unable to control their actions) and inflated SoA (having "magical" control over events). The present review investigated the extent to which the SoA is distorted in OCD, in terms of both implicit (ie, inferred from correlates and outcomes of voluntary actions) and explicit (ie, subjective judgment of one's control over an outcome) measures of SoA.

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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.

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Symptoms of obsessive-compulsive disorder are related to atypical sensory processing, particularly sensory over-responsivity, in both children and adults. In adults, obsessive-compulsive symptoms are also associated with the attenuation of access to the internal state and compensatory reliance on proxies for these states, including fixed rules and rituals. We aimed to examine the associations between sensory over-responsivity, the tendency to seek proxies for internal states, and obsessive-compulsive symptoms in children.

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The Seeking Proxies for Internal States (SPIS) model of obsessive-compulsive disorder (OCD) explains symptoms of OCD as stemming from attenuated access to internal states, which is compensated for by using proxies, which are indices of these states that are more discernible or less ambiguous. Internal states in the SPIS model are subjective states that are not accessible to others, encompassing physiological states, motivations, preferences, memories, and emotions. Compensatory proxies in OCD include fixed rules and rituals as well as seeking and relying on external information.

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Introduction: Cognitive models of obsessive-compulsive disorder (OCD) implicate heightened attention allocation to stimuli related to one's obsessions in the disorder. Recently, to overcome several limitations of reaction time-based measures, eye-tracking methodology has been increasingly used in attentional research.

Methods: A meta-analysis of studies examining attention allocation towards OCD-related vs.

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People with obsessive-compulsive disorder (OCD) tend to distrust their memory, perception, and other cognitive functions, and many OCD symptoms can be traced to diminished confidence in one's cognitive processes. For example, poor confidence in recall accuracy can cause doubt about one's memory and motivate repeated checking. At the same time, people with OCD also display performance deficits in a variety of cognitive tasks, so their reduced confidence must be evaluated in relation to their actual performance.

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The Seeking Proxies for Internal States (SPIS) model of obsessive-compulsive disorder (OCD) posits that OCD is associated with attenuated access to internal states. Here we explored the implications of this model in the realm of emotions. Participants with OCD, anxiety disorders, and nonclinical control participants completed the Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT), assessing two domains of emotional intelligence: Experiential emotional intelligence (EI), reflecting the ability to perceive and feel emotions accurately, and Strategic EI, reflecting the ability to understand and manage emotions correctly.

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The Seeking Proxies for Internal States (SPIS) model of obsessive-compulsive disorder (OCD) proposes an account of OCD symptoms in terms of two core components: attenuation of access to internal states and seeking proxies for internal states. Specifically, the SPIS model posits that OCD is associated with difficulty in accessing various internal states, including feelings, preferences, memories, and even physiological states. This difficulty drives obsessive-compulsive individuals seek and rely on compensatory proxies, or substitutes, for their internal states.

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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.

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Individuals with obsessive-compulsive disorder (OCD) tend to report higher levels of disgust, but not much is known about factors that might underlie this relationship. The present study was motivated by the behavioral immune theory, which suggests that disgust has evolved as a protective reaction to potential presence of disease agents in the immediate environment. We examined the relationships between the intensity of experienced physical disgust, perceived vulnerability to disease, and OCD symptoms.

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Background: The Seeking Proxies for Internal States (SPIS) model of OCD asserts that obsessive-compulsive (OC) tendencies are associated with attenuated access to internal states. Here we explore the implications of this model for awareness of emotional valence.

Methods: In Study 1, participants with high and low OC tendencies (n = 30 in each group) rated how they felt while viewing different pictures with positive, neutral, or negative valence taken from the International Affective Picture System.

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Background And Objectives: The Seeking Proxies for Internal States (SPIS) model of obsessive-compulsive disorder (OCD) posits that obsessive-compulsive (OC) individuals have attenuated access to their internal states. Hence, they seek and rely on proxies, or discernible substitutes for these internal states. In previous studies, participants with high OC tendencies and OCD patients, compared to controls, showed increased reliance on external proxies and were more influenced by false feedback when judging their internal states.

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Background And Objectives: The Seeking Proxies for Internal States (SPIS) model of obsessive-compulsive disorder (OCD) postulates that obsessive-compulsive (OC) individuals have reduced access to their internal states and must therefore seek and rely on external proxies for these states. The present study extended this hypothesis to the feeling of understanding, which had not been examined previously in relation to OCD.

Methods: We presented 148 participants with a computerized task requiring them to read and understand a text on medieval architecture.

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The Yale-Brown Obsessive Compulsive Scale (Y-BOCS) is the most common measure of Obsessive-Compulsive symptom severity. The Y-BOCS interview is considered gold standard, but its self-rating format is increasingly used in clinical trials. Few studies investigated congruency and potential changes over treatment.

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Background And Objectives: In recent years we have proposed and investigated the Seeking Proxies for Internal States (SPIS) model of obsessive-compulsive disorder (OCD), which postulates that deficient access to internal states is a key feature of the disorder. According to this model, rules and rituals that often characterize people with OCD can be understood as proxies for deficiently accessible internal states. Here we compliment this earlier experimental work by examining whether reliance on proxies for internal states in everyday life is associated with OCD.

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The present studies were motivated by the hypothesis that attenuated access to internal states in obsessive-compulsive (OC) individuals, which leads to extensive reliance on external proxies, may manifest in a maximizing decision making style, i.e., to seeking the best option through an exhaustive search of all existing alternatives.

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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.

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Background And Objectives: The Seeking Proxies for Internal States model of OCD posits that obsessive-compulsive (OC) individuals have attenuated access to their internal states. Consequently, they seek and rely on discernible substitutes for these internal states. Previous research has supported these conjectures.

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Introduction: Smartphone applications (apps) for smoking cessation are becoming increasingly available, but their efficacy remains to be demonstrated. We conducted a pilot study of SmokeBeat, a novel app designed for use with smartwatches and wristbands. SmokeBeat is powered by a data analytics software platform that processes information from the sensors embedded in wearables.

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The sense of agency (SoA) is defined as "the registration that I am the initiator of my actions." Both "direct" and "indirect" measurement of SoA has focused on specific contextualized perceptual events, however it has also been demonstrated that "higher level" cognitions seemingly affect the SoA. We designed a measure of person's general, context-free beliefs about having core agency-the Sense of Agency Scale (SoAS).

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Background: Obsessive Compulsive Disorder (OCD) is a chronic and disabling disorder with poor response to pharmacological treatments. Converging evidences suggest that OCD patients suffer from dysfunction of the cortico-striato-thalamo-cortical (CSTC) circuit, including in the medial prefrontal cortex (mPFC) and the anterior cingulate cortex (ACC).

Objective: To examine whether modulation of mPFC-ACC activity by deep transcranial magnetic stimulation (DTMS) affects OCD symptoms.

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Nicotine has been proposed to be a primary reinforcer and a reinforcement enhancer. To date, no studies have examined whether nicotine enhances consummatory behaviors or only operant responding (appetitive behaviors). Experiments were designed to test whether contingent and noncontingent nicotine enhance lever pressing for and consumption of fluids in water-deprived rats.

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The effect of threatened morality on negative emotions and on altruistic behaviour has been shown to diminish following physical cleansing (hand-washing). We hypothesised that threatened morality will broadly impair the executive control system, and that physical cleansing will moderate this detrimental effect. Thirty-seven participants were asked to write about an immoral deed they had committed, whereupon half of them were allowed to wipe their hands.

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One of the main characteristics of obsessive-compulsive disorder (OCD) is the persistent feeling of uncertainty, affecting many domains of actions and feelings. It was recently hypothesized that OCD uncertainty is related to attenuated access to internal states. As supra-second timing is associated with bodily and interoceptive awareness, we examined whether supra-second timing would be associated with OC tendencies.

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