Video telemetry and behavioral analysis discriminate between compulsive cleaning and compulsive checking in obsessive-compulsive disorder

Uncovering the Motor Dynamics of Obsessive-Compulsive Rituals Through Cluster Analysis

ABSTRACT

Rituals represent a prominent human behavior in different contexts such as daily routines, life cycle stages, and psychopathology, for example, obsessive compulsive disorder (OCD) where they are referred to as compulsions. OCD compulsions differ from habitual behaviors and stereotypies regarding their formal features: acts repetition, the addition of nonfunctional acts, and attentional focus on basic motor units. This study aims to categorize OCD compulsions based on the motor patterns of acts repetition and inclusion of nonfunctional acts. We analyzed 28 video-recorded OCD compulsions; we adopted a cluster analytic model to identify distinct patterns within the data and determine cluster characteristics. Our findings revealed a moderate negative covariance between nonfunctionality and repetitiveness, indicating that as nonfunctionality increased, repetitiveness decreased. Three distinct clusters in OCD rituals were identified according to the motor pattern: "idiosyncratic rituals," characterized by strong incorporation of nonfunctional acts; "iterative rituals" showing high repetitiveness; and "routines," with minimal repetition and limited inclusion of nonfunctional acts. These motor patterns highlight evolutionarily conserved behavioral strategies aimed at coping with conditions of environmental unpredictability. The findings might allow fine-grained discrimination of ritual compulsions and help target personalized interventions.

The Use of Immersive Environments for the Early Detection and Treatment of Neuropsychiatric Disorders

Neuropsychiatric disorders are highly prevalent conditions with significant individual, societal, and economic impacts. A major challenge in the diagnosis and treatment of these conditions is the lack of sensitive, reliable, objective, quantitative tools to inform diagnosis, and measure symptom severity. Currently available assays rely on self-reports and clinician observations, leading to subjective analysis. As a step toward creating quantitative assays of neuropsychiatric symptoms, we propose an immersive environment to track behaviors relevant to neuropsychiatric symptomatology and to systematically study the effect of environmental contexts on certain behaviors. Moreover, the overarching theme leads to connected tele-psychiatry which can provide effective assessment.

Social spatial cognition

Social spatial cognition refers to the interaction between self, place, and partners, with emphasis on the impact of the social environment on spatial behavior and on how individual spatial representations converge to form collective spatial behavior - i.e., common places and routes. Recent studies suggest that in addition to their mental representation (cognitive map) of the physical environment, humans and other animals also have a social cognitive map. We suggest that while social spatial cognition relies on knowledge of both the physical and the social environments, it is the latter hat predominates. This dominance is illustrated here in the modulation of spatial behavior according to dynamic social interactions, ranging from group formation to an attenuation of drug-induced stereotypy through the mere presence of a normal subject. Consequently we suggest that the numerous studies on the biobehavioral controlling mechanisms of spatial behavior (i.e. - the hippocampal formation, animal models for mental disorders) should also consider the social environment rather than solely focusing on the spatial behavior of lone animals.

Obsessive-compulsive disorder: Insights from animal models

Research with animal models of obsessive-compulsive disorder (OCD) shows the following: (1) Optogenetic studies in mice provide evidence for a plausible cause-effect relation between increased activity in cortico-basal ganglia-thalamo-cortical (CBGTC) circuits and OCD by demonstrating the induction of compulsive behavior with the experimental manipulation of the CBGTC circuit. (2) Parallel use of several animal models is a fruitful paradigm to examine the mechanisms of treatment effects of deep brain stimulation in distinct OCD endophenotypes. (3) Features of spontaneous behavior in deer mice constitute a rich platform to investigate the neurobiology of OCD, social ramifications of a compulsive phenotype, and test novel drugs. (4) Studies in animal models for psychiatric disorders comorbid with OCD suggest comorbidity may involve shared neural circuits controlling expression of compulsive behavior. (5) Analysis of compulsive behavior into its constitutive components provides evidence from an animal model for a motivational perspective on OCD. (6) Methods of behavioral analysis in an animal model translate to dissection of compulsive rituals in OCD patients, leading to diagnostic tests.

Are nonclinical obsessive-compulsive symptoms associated with bias toward habits?

In a sample of student volunteers (N=93), we found that obsessive-compulsive symptoms (although not hoarding) were associated with overreliance on stimulus-response habits at the expense of goal-directed control during instrumental responding. Only checking symptoms were associated with bias toward habits after negative affect was controlled for. Further research is warranted to examine if overreliance on habits represents an aberrant learning process that confers risk for obsessive-compulsive psychopathology.

Symptom dimensions, clinical course and comorbidity in men and women with obsessive-compulsive disorder

The study aimed to compare male and female patients with obsessive-compulsive disorder (OCD) across symptom dimensions, clinical course and comorbidity. A cross-sectional study was undertaken with 858 adult OCD patients (DSM-IV) from the Brazilian Research Consortium on Obsessive-Compulsive Spectrum Disorders. Patients were evaluated using structured interviews, including the Dimensional Yale-Brown Obsessive-Compulsive Scale (DY-BOCS) and the Structured Clinical Interview for DSM-IV Axis I disorders (SCID-I). The sample was composed of 504 women (58.7%) and 354 men (41.3%) with a mean age of 35.4 years-old (range: 18-77). Men were younger, more frequently single and presented more tics, social phobia and alcohol use disorders. Among men, symptom interference occurred earlier and symptoms of the sexual/religious dimension were more common and more severe. Conversely, women were more likely to present symptoms of the aggressive, contamination/cleaning and hoarding dimension and comorbidity with specific phobias, anorexia nervosa, bulimia, trichotillomania, skin picking and "compulsive" buying. In the logistic regression, female gender remained independently associated with the aggressive and contamination/cleaning dimensions. In both genders the aggressive dimension remained associated with comorbid post-traumatic stress disorder, the sexual/religious dimension with major depression and the hoarding dimension with tic disorders. Gender seems to be relevant in the determination of OCD clinical presentation and course and should be considered an important aspect when defining more homogeneous OCD subgroups.

The impact of precaution and practice on the performance of a risky motor task

The association between threat perception and motor execution, mediated by evolved precaution systems, often results in ritual-like behavior, including many idiosyncratic acts that seem irrelevant to the task at hand. This study tested the hypothesis that threat-detection during performance of a risky motor task would result in idiosyncratic activity that is not necessary for task completion. We asked biology students to follow a particular set of instructions in mixing three solutions labeled "bio-hazardous" and then repeat this operation with "non-hazardous" substances (or vice versa). We observed a longer duration of the overall performance, a greater repertoire of acts, longer maximal act duration, and longer mean duration of acts in the "risky" task when it was performed before the "non-risky" task. Some, but not all, of these differences were eliminated when a "non-risky" task preceded the "risky" one. The increased performance of idiosyncratic unnecessary activity is in accordance with the working hypothesis of the present study: ritualized idiosyncratic activities are performed in response to a real or illusionary threat, as a means to alleviate anxiety.

Disgust and fear responding in contamination-based obsessive-compulsive disorder during pictorial exposure

The emotion of disgust has been implicated in the development and maintenance of contamination-based obsessive-compulsive disorder (OCD). In the present study nonclinical participants with high (n=26) and low (n=28) levels of OCD contamination symptoms were exposed to 2 categories of disgust stimuli (blood injury and body waste) across 4 blocks using standardized disgust images. Self-report disgust and fear were recorded, as well as cardiovascular heart rate. In both groups, an initial primary disgust reaction was observed. Self-report disgust and fear, but not heart rate deceleration, was greater in the high symptom group. The high symptom group showed reductions in heart rate deceleration, whereas the low symptom group did not. Significant differences in self-report changes across time were observed between the groups, with fear increasing to a greater extent for high contamination fearful individuals when viewing body waste images. The implications of these findings for theoretical models and clinical treatment of OCD with prominent contamination symptoms are discussed.

Comparison of checking behavior in adults with or without checking symptom of obsessive-compulsive disorder using a novel computer-based measure

Easy to administer behavioral measures of checking are needed to improve the assessment of this hallmark feature of OCD. We recently developed a new computer-based behavioral assessment of OCD in a previous study. As a follow-up experiment for this method, the goal of this study was to examine whether the new computer-based behavioral assessment would be capable of differentiating behaviors in adults with OCD characterized by checking behavior from those without checking behavior. We compared 22 OCD patients with compulsive checking behaviors (OCD checkers), 17 OCD controls without checking behavior (OCD controls), and 31 healthy controls (HCs) on a novel computer-based behavioral measure of checking behavior. Despite similar levels of successfully completed tasks, OCD checkers demonstrated longer duration of checking behaviors than OCD controls or HCs. Interestingly, no differences were found between OCD controls and HCs in any of the dependent variables. Our new behavioral measure offers a novel, objective, and ecologically valid measure of checking behaviors in a sample of adults with OCD.

Manifestation of incompleteness in obsessive-compulsive disorder (OCD) as reduced functionality and extended activity beyond task completion

BACKGROUND

This study focused on hypotheses regarding the source of incompleteness in obsessive-compulsive disorder (OCD). For this, we had to document the behavioral manifestation of incompleteness in compulsive rituals, predicting that an exaggerated focus on acts that are appropriate for the task will support the hypothesis on heightened responsibility/perfectionism. In contrast, activity past the expected terminal act for the motor task would support the "stop signal deficiency" hypothesis.

METHODOLOGY AND PRINCIPAL FINDINGS

We employed video-telemetry to analyze 39 motor OCD rituals and compared each with a similar task performed by a non-OCD individual, in order to objectively and explicitly determine the functional end of the activity. We found that 75% of OCD rituals comprised a "tail," which is a section that follows the functional end of the task that the patients ascribed to their activity. The other 25% tailless rituals comprised a relatively high number and higher rate of repetition of non-functional acts. Thus, in rituals with tail, incompleteness was manifested by the mere presence of the tail whereas in tailless rituals, incompleteness was manifested by the reduced functionality of the task due to an inflated execution and repetition of non-functional acts.

CONCLUSIONS

The prevalence of activity after the functional end ("tail") and the elevated non-functionality in OCD motor rituals support the "lack of stop signal" theories as the underlying mechanism in OCD. Furthermore, the presence and content of the tail might have a therapeutic potential in cognitive-behavior therapy.