Obsessions and Time of Day: A Self-Monitoring Study in Individuals With Obsessive-Compulsive Disorder

Closed-loop neurostimulation for the treatment of psychiatric disorders

Despite increasing prevalence and huge personal and societal burden, psychiatric diseases still lack treatments which can control symptoms for a large fraction of patients. Increasing insight into the neurobiology underlying these diseases has demonstrated wide-ranging aberrant activity and functioning in multiple brain circuits and networks. Together with varied presentation and symptoms, this makes one-size-fits-all treatment a challenge. There has been a resurgence of interest in the use of neurostimulation as a treatment for psychiatric diseases. Initial studies using continuous open-loop stimulation, in which clinicians adjusted stimulation parameters during patient visits, showed promise but also mixed results. Given the periodic nature and fluctuations of symptoms often observed in psychiatric illnesses, the use of device-driven closed-loop stimulation may provide more effective therapy. The use of a biomarker, which is correlated with specific symptoms, to deliver stimulation only during symptomatic periods allows for the personalized therapy needed for such heterogeneous disorders. Here, we provide the reader with background motivating the use of closed-loop neurostimulation for the treatment of psychiatric disorders. We review foundational studies of open- and closed-loop neurostimulation for neuropsychiatric indications, focusing on deep brain stimulation, and discuss key considerations when designing and implementing closed-loop neurostimulation.

Psychometric properties of a daily obsessive-compulsive symptom scale for ecological momentary assessment

Despite growing interest in ecological momentary assessment (EMA) in psychopathology and clinical observation of day-to-day fluctuations in obsessive-compulsive disorder (OCD) symptoms, there is not a standardized EMA measure of such symptoms that can guide systematic research. In the absence of such a measure, prior EMA research in OCD has utilized heterogeneous approaches to sampling momentary and daily OCD symptoms, which limits the ability to compare results between studies. The present study sought to examine the psychometric properties of a daily OCD symptom (d-OCS) measure that assesses common OCD symptom themes (e.g., contamination, checking, intrusive thoughts) in a sample of adults with OCD (n = 20), psychiatric controls (n = 27), and healthy controls (n = 27). Participants completed the d-OCS 3 times per day for 1 week. The d-OCS distinguished those with OCD from psychiatric controls and healthy controls. The d-OCS demonstrated good internal consistency, adequate test-retest reliability, and good convergent validity. These findings offer initial psychometric support for the use of the d-OCS in EMA research examining day-to-day fluctuations in symptoms of OCD. Additional investigation is needed to examine the discriminant validity of the d-OCS and generalize these findings to more diverse samples.

The Effect of Symptom-Provocation on Inhibitory Control in Obsessive-Compulsive Disorder Patients Is Contingent upon Chronotype and Time of Day

Studies have shown that alertness can affect inhibitory control, the mechanism responsible for stopping behaviors, thoughts, or emotions. Inhibitory control is particularly important for helping individuals with Obsessive-Compulsive Disorder (OCD) resisting their symptoms. Chronotype is the mechanism governing an individual's fluctuation of alertness throughout the day. Previous studies have shown that individuals with a 'morning' chronotype have worse OCD symptoms in the evening and vice versa. We administered a novel 'symptom-provocation stop signal task' (SP-SST), in which individually tailored OCD triggers were presented and inhibitory control was measured. Twenty-five treatment-seeking OCD patients completed the SP-SST three times per day for seven consecutive days. Stop signal reaction time (SSRT), which measures inhibitory control, was calculated separately for symptom-provocation trials and for neutral trials. Results yielded that: (a) stopping was significantly harder in the symptom-provocation compared to neutral trials, and (b) the chronotype by time-of-day interaction predicts inhibition for both symptom-provocation and neutral trials, indicating better inhibition in the optimal time of day. Furthermore, we concluded that individually tailored OCD triggers have a detrimental effect on inhibitory control. Most importantly, higher alertness levels, which can be predicted by the interaction of chronotype and time of day, affect inhibitory control, both in general and for OCD triggers specifically.

Possible actions of cannabidiol in obsessive-compulsive disorder by targeting the WNT/β-catenin pathway

Obsessive-compulsive disorder (OCD) is a neuropsychiatric disorder characterized by recurrent and distinctive obsessions and/or compulsions. The etiologies remain unclear. Recent findings have shown that oxidative stress, inflammation, and glutamatergic pathways play key roles in the causes of OCD. However, first-line therapies include cognitive-behavioral therapy but only 40% of the patients respond to this first-line therapy. Research for new treatment is mandatory. This review focuses on the potential effects of cannabidiol (CBD), as a potential therapeutic strategy, on OCD and some of the presumed mechanisms by which CBD provides its benefit properties. CBD medication downregulates GSK-3β, the main inhibitor of the WNT/β-catenin pathway. The activation of the WNT/β-catenin could be associated with the control of oxidative stress, inflammation, and glutamatergic pathway and circadian rhythms dysregulation in OCD. Future prospective clinical trials could focus on CBD and its different and multiple interactions in OCD.

Long-term ecological assessment of intracranial electrophysiology synchronized to behavioral markers in obsessive-compulsive disorder

Detection of neural signatures related to pathological behavioral states could enable adaptive deep brain stimulation (DBS), a potential strategy for improving efficacy of DBS for neurological and psychiatric disorders. This approach requires identifying neural biomarkers of relevant behavioral states, a task best performed in ecologically valid environments. Here, in human participants with obsessive-compulsive disorder (OCD) implanted with recording-capable DBS devices, we synchronized chronic ventral striatum local field potentials with relevant, disease-specific behaviors. We captured over 1,000 h of local field potentials in the clinic and at home during unstructured activity, as well as during DBS and exposure therapy. The wide range of symptom severity over which the data were captured allowed us to identify candidate neural biomarkers of OCD symptom intensity. This work demonstrates the feasibility and utility of capturing chronic intracranial electrophysiology during daily symptom fluctuations to enable neural biomarker identification, a prerequisite for future development of adaptive DBS for OCD and other psychiatric disorders.

Waxing and waning: The roles of chronotype and time of day in predicting symptom fluctuations in obsessive-compulsive disorder using a daily-monitoring design

Obsessive-compulsive disorder (OCD) symptoms fluctuate throughout the day, but scientists are not sure what underlies these fluctuations. One factor which may explain how OCD symptoms wax and wane throughout the day is alertness. Increased alertness is associated with greater inhibitory control, a factor which plays a significant role in patients' ability to overcome their OCD symptoms. The current study examined the relationship between chronotype (morningness/eveningness preference, a measure of alertness) and within-day OCD symptom severity fluctuations. We hypothesized that increased alertness leads to better inhibitory abilities and, therefore, reduced OCD symptoms. OCD Symptoms were measured through 7-days of monitoring in which participants were asked to retrospectively rate their symptoms at several timepoints throughout the day. Chronotype was measured using the Morningness/Eveningness Questionnaire (MEQ). Consistent with our hypotheses, results revealed an interaction between chronotype and time of day, such that those with an eveningness preference tended to have worse symptoms in the morning, and vice versa. In addition, we also report novel findings regarding the effect of bedtime, sleep duration, and sleep quality on symptom severity the next day. Taken together, these findings suggest that alertness may modulate OCD symptom severity throughout the day such that individuals experience more severe symptoms during times of low alertness. The clinical and theoretical implications of these findings are discussed.

Circadian Rhythms in Obsessive-Compulsive Disorder: Recent Findings and Recommendations for Future Research

PURPOSE OF REVIEW

Circadian rhythms are a topic of growing interest in mental health, particularly in obsessive-compulsive disorder. However, the consistency of this link has not been carefully examined. Thus, the present review integrates findings from the past 5 years in order to determine the strength of such a relationship and identify areas for clarification and extension.

RECENT FINDINGS

Findings revealed inconsistent evidence for a link between circadian rhythms and OCD. Chronotype is unrelated to OCD symptoms in adolescents but predicts OCD symptoms in adults. Results on delayed sleep timing are equivocal. Circadian rhythm disorders predict OCD treatment outcome. Preliminary evidence implicates decreased light exposure and diurnal symptom variability in OCD. The relationship between circadian rhythms and OCD may vary by age, diagnostic status, and assessment method. Recent findings are limited by an overreliance on convenience samples and singular self-report methods. Recommendations for future research on the role of circadian rhythms in OCD are discussed.

Time of day effects on the relationship between daily sleep and anxiety: An ecological momentary assessment approach

Previous research has linked sleep disturbance to anxiety. However, evidence for this relation has been inconsistent, largely limited to retrospective reports that do not account for daily variability, and silent on when the association is most pronounced. Thus, the present study utilized ecological momentary assessment (EMA) to examine the effects of daily deviations in total sleep time (TST) and person-average TST on anxiety and whether these effects varied as a function of time of day in a sample of unselected adults (N = 138). Results indicate that the amount of TST on a given night, relative to personal average TST, negatively predicted anxiety, and this relation was significant in the morning and afternoon, but not evening. In contrast, person-average TST was unrelated to average anxiety. Relations between TST and anxiety did not differ across objective (e.g., actigraphy) and subjective (e.g., sleep diary) measures. Furthermore, the pattern of results remained the same when controlling for previous day's anxiety and were not bidirectional. These findings suggest that getting less sleep than is typical for the individual predicts subsequent anxiety, and this effect is particularly strong in the morning. Average sleep duration may be less important to the experience of anxiety than deviations from that average. These findings highlight the importance of EMA to examine how and when variability in sleep confers vulnerability for anxiety symptoms.

Sleep, arousal, and circadian rhythms in adults with obsessive-compulsive disorder: a meta-analysis

Findings of this meta-analysis show that obsessive-compulsive disorder (OCD) is related to disruptions in both the duration and timing of sleep. PsycINFO and Google Scholar database searches identified 12 relevant studies that compared measures of sleep in individuals with OCD to those of either a healthy control group or published norms. Sleep measures included sleep onset latency, sleep duration, awakening after sleep onset, percentage of rapid eye movement (REM) sleep, percentage of slow wave sleep, and prevalence of delayed sleep phase disorder (DSPD). Individual effect sizes were pooled using a random effects model. Sleep duration was found to be shorter, and the prevalence of DSPD higher, in individuals with OCD compared to controls. Further, excluding samples with comorbid depression did not meaningfully reduce the magnitude of these effects (although the results were no longer statistically significant) and medication use by participants is unlikely to have systematically altered sleep timing. Overall, available data suggest that sleep disruption is associated with OCD but further research on both sleep duration and sleep timing in individuals with OCD is needed.