Relationships between interoceptive sensibility and resting-state functional connectivity of the insula in obsessive-compulsive disorder

The relationship between sensory phenomena and interoception across the obsessive-compulsive spectrum: a systematic review

BACKGROUND

Uncomfortable sensations preceding repetitive behaviours, known as sensory phenomena, have been documented across the obsessive-compulsive spectrum. Indirect evidence suggests altered interoception may play a role in these shared experiences of sensory phenomena; however, research explicitly measuring this relationship is limited. The current systematic review aimed to establish the nature of sensory phenomena and interoception in obsessive-compulsive and related disorders (OCRDs) and tic disorders as potential maintaining factors of these disorders.

METHODS

PsycINFO, PubMed, and Scopus databases were searched from 2007 to April 2024, yielding 65 studies.

RESULTS

While the majority of studies presented low risk of bias, significant overlap and ambiguity characterised the measurement and conceptualisation of sensory phenomena and interoception. Overall, higher sensory phenomena was associated with greater symptom severity in several obsessive-compulsive spectrum disorders. Obsessive-compulsive disorder and tic disorder samples were characterised by lower interoceptive accuracy, with mixed findings on interoceptive sensibility. Some limited research emerged suggesting altered interoceptive abilities may be associated with greater sensory phenomena in obsessive-compulsive disorder and tic disorders.

CONCLUSIONS

Sensory phenomena are experienced across the obsessive-compulsive spectrum. Future research should explore interoceptive abilities across the OCRDs, and build upon evidence supporting a relationship between sensory phenomena and interoception in OCD and tic disorders.

TRIAL REGISTRATION

CRD42023422817.

Identifying subgroups of urge suppression in Obsessive-Compulsive Disorder using machine learning

Obsessive-compulsive disorder (OCD) is phenomenologically heterogeneous. While predominant models suggest fear and harm prevention drive compulsions, many patients also experience uncomfortable sensory-based urges ("sensory phenomena") that may be associated with heightened interoceptive sensitivity. Using an urge-to-blink eyeblink suppression paradigm to model sensory-based urges, we previously found that OCD patients as a group had more eyeblink suppression failures and greater activation of sensorimotor-interoceptive regions than controls. However, conventional approaches assuming OCD homogeneity may obscure important within-group variability, impeding precision treatment development. This study investigated the heterogeneity of urge suppression failure in OCD and examined relationships with clinical characteristics and neural activation. Eighty-two patients with OCD and 38 controls underwent an fMRI task presenting 60-s blocks of eyeblink suppression alternating with free-blinking blocks. Latent profile analysis identified OCD subgroups based on number of erroneous blinks during suppression. Subgroups were compared on behavior, clinical characteristics, and brain activation during task. Three patient subgroups were identified. Despite similar overall OCD severity, the subgroup with the most erroneous eyeblinks had the highest sensory phenomena severity, interoceptive sensitivity, and subjective urge intensity. Compared to other subgroups, this subgroup exhibited more neural activity in somatosensory and interoceptive regions during the early phase (first 30 s) of blink suppression and reduced activity in the middle frontal gyrus during the late phase (second 30 s) as the suppression period elapsed. Heterogeneity of urge suppression in OCD was associated with clinical characteristics and brain function. Our results reveal potential treatment targets that could inform personalized medicine.

Sensory over-responsivity and orbitofrontal cortex connectivity in obsessive-compulsive disorder

BACKGROUND

Sensory over-responsivity (SOR) in obsessive-compulsive disorder (OCD) is associated with illness severity and functional impairment. However, the neural substrates of SOR in OCD have not yet been directly probed.

METHODS

We examined resting-state global functional connectivity markers of SOR in 119 adults with OCD utilizing the CONN-fMRI Functional Connectivity Toolbox for SPM (v21a). We quantified SOR with the sensory sensitivity and sensory avoiding subscales of the Adult and Adolescent Sensory Profile (AASP). We also measured: OCD severity, with the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) and Obsessive-Compulsive Inventory-Revised (OCI-R); sensory phenomena with the Sensory Phenomena Scale (SPS); general anxiety, with the Beck Anxiety Inventory (BAI); and depressive symptomatology, with Quick Inventory of Depressive Symptoms, Self-Report (QIDS-SR).

RESULTS

There was a significant positive relationship of SOR with global connectivity in anterior and medial OFC (Brodmanns area 11, k = 154, x = 14, y = 62, z = -18, whole-brain corrected at FWE p < 0.05).

LIMITATIONS

Future investigations should explore neural responses to sensory stimulation tasks in OCD and compare findings with those obtained in other conditions also characterized by high SOR, such as autism spectrum disorder.

CONCLUSIONS

This study implicates OFC functional connectivity as a neurobiological mechanism of SOR in OCD and suggests that the substrates of SOR in OCD may be dissociable from both that of other symptoms in OCD, and SOR in other disorders. With replication and extension, the finding may be leveraged to develop and refine treatments for OCD and investigate the pathophysiology of SOR in other conditions.

Insula-cortico-subcortical networks predict interoceptive awareness and stress resilience

BACKGROUND

Interoception, the neural sensing of visceral signals, and interoceptive awareness (IA), the conscious perception of interoception, are crucial for life survival functions and mental health. Resilience, the capacity to overcome adversity, has been associated with reduced interoceptive disturbances. Here, we sought evidence for our Insula Modular Active Control (IMAC) model that suggest that the insula, a brain region specialized in the processing of interoceptive information, realizes IA and contributes to resilience and mental health via cortico-subcortical connections.

METHODS

64 healthy participants (32 females; ages 18-34 years) answered questionnaires that assess IA and resilience. Mental health was evaluated with the Beck Depression Inventory II that assesses depressive mood. Participants also underwent a 15 minute resting-state functional resonance imaging session. Pearson correlations and mediation analyses were used to investigate the relationship between IA and resilience and their contributions to depressive mood. We then performed insula seed-based functional connectivity analyzes to identify insula networks involved in IA, resilience and depressive mood.

RESULTS

We first demonstrated that resilience mediates the relationship between IA and depressive mood. Second, shared and distinct intra-insula, insula-cortical and insula-subcortical networks were associated with IA, resilience and also predicted the degree of experienced depressive mood. Third, while resilience was associated with stronger insula-precuneus, insula-cerebellum and insula-prefrontal networks, IA was linked with stronger intra-insula, insula-striatum and insula-motor networks.

CONCLUSIONS

Our findings help understand the roles of insula-cortico-subcortical networks in IA and resilience. These results also highlight the potential use of insula networks as biomarkers for depression prediction.

The Seeking Proxies for Internal States (SPIS) Model of OCD - A Comprehensive Review of Current Findings and Implications for Future Directions

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. In the present review, we outline the SPIS model and describe its basic tenets. We then use the SPIS conceptualization to explain two pivotal OCD-related phenomena - obsessive doubt and compulsive rituals. Next, we provide a detailed overview of current empirical evidence supporting the SPIS in several domains, including physiological states, emotions, sense of understanding, decision-making, and sense of agency. We conclude by discussing possible neural correlates of the difficulty in accessing internal states, focusing on the anterior insular cortex (AIC) and highlighting potential clinical implications of the model to the treatment of OCD.

Associations Between Suicidality and Interoception in Obsessive-Compulsive Disorder

Background

Individuals with obsessive-compulsive disorder (OCD) are at increased risk for suicide. One potential risk factor is interoceptive sensibility (IS), which is one's subjective experience of bodily sensations. The current study examined the relationship between IS and current suicidal ideation and lifetime history of suicide attempt, controlling for relevant covariates.

Methods

Participants (N = 145) were a clinical sample of individuals with OCD from the New York City area. A clinical rater administered a diagnostic interview and an OCD severity assessment, and participants completed questionnaires about demographics, IS, and suicidality.

Results

Current suicidal ideation was associated with reduced trusting of the body, and lifetime history of suicide attempt was related to greater general awareness of sensation. These associations remained significant after controlling for covariates.

Conclusions

These results suggest that specific facets of IS may be associated with specific domains of suicidality. Decreased body trusting may represent a feeling of disconnection from the body that facilitates desire for death. Increased noticing of bodily sensations may lead to greater mental pain, which could interact with deficits in emotion regulation to increase risk for suicide attempt. Further research on the relationships between IS and suicidality in OCD is warranted.

Abnormal resting-state functional connectivity of the insula in medication-free patients with obsessive-compulsive disorder

BACKGROUND

The function of the insula has been increasingly mentioned in neurocircuitry models of obsessive-compulsive disorder (OCD) for its role in affective processing and regulating anxiety and its wide interactions with the classic cortico-striato-thalamo-cortical circuit. However, the insular resting-state functional connectivity patterns in OCD remain unclear. Therefore, we aimed to investigate characteristic intrinsic connectivity alterations of the insula in OCD and their associations with clinical features.

METHODS

We obtained resting-state functional magnetic resonance imaging data from 85 drug-free OCD patients and 85 age- and sex-matched healthy controls (HCs). We performed a general linear model to compare the whole-brain intrinsic functional connectivity maps of the bilateral insula between the OCD and HC groups. In addition, we further explored the relationship between the intrinsic functional connectivity alterations of the insula and clinical features using Pearson or Spearman correlation analysis.

RESULTS

Compared with HCs, patients with OCD exhibited increased intrinsic connectivity between the bilateral insula and bilateral precuneus gyrus extending to the inferior parietal lobule and supplementary motor area. Decreased intrinsic connectivity was only found between the right insula and bilateral lingual gyrus in OCD patients relative to HC subjects, which was negatively correlated with the severity of depression symptoms in the OCD group.

CONCLUSION

In the current study, we identified impaired insular intrinsic connectivity in OCD patients and the dysconnectivity of the right insula and bilateral lingual gyrus associated with the depressive severity of OCD patients. These findings provide neuroimaging evidence for the involvement of the insula in OCD and suggest its potential role in the depressive symptoms of OCD.

Altered Interoceptive Sensibility in Adults With Chronic Tic Disorder

BACKGROUND

Interoception refers to the sensing, interpretation, integration, and regulation of signals about the body's internal physiological state. Interoceptive sensibility is the subjective evaluation of interoceptive experience, as assessed by self-report measures, and is abnormal in numerous neuropsychiatric disorders. Research examining interoceptive sensibility in individuals with chronic tic disorders (CTDs), however, has yielded conflicting results, likely due to methodologic differences between studies and small sample sizes.

OBJECTIVE

We sought to compare interoceptive sensibility between adults with CTD and healthy controls, adjusting for co-occurring psychiatric symptoms, and to examine the relationship of interoceptive sensibility with other CTD clinical features, in particular, premonitory urge.

METHODS

We recruited adults with CTDs and sex- and age-matched healthy controls to complete the Multidimensional Assessment of Interoceptive Awareness, Version 2 (MAIA-2), as well as a battery of measures assessing psychiatric symptoms prevalent in CTD populations. CTD participants additionally completed scales quantifying tic severity, premonitory urge severity, and health-related quality of life. We conducted between-group contrasts (Wilcoxon rank-sum test) for each MAIA-2 subscale, analyzed the effect of psychiatric symptoms on identified between-group differences (multivariable linear regression), and examined within-group relationships between MAIA-2 subscales and other clinical measures (Spearman rank correlations, multivariable linear regression).

RESULTS

Between adults with CTD (n = 48) and healthy controls (n = 48), MAIA-2 Noticing and Not-Worrying subscale scores significantly differed. After adjusting for covariates, lower MAIA-2 Not-Worrying subscale scores were significantly associated with female sex (β = 0.42, p < 0.05) and greater severity of obsessive-compulsive symptoms (β = -0.028, p < 0.01), but not with CTD diagnosis. After adjusting for severity of tics and obsessive-compulsive symptoms, a composite of MAIA-2 Noticing, Attention Regulation, Emotional Awareness, Self-Regulation, Body Listening, and Trusting subscales (β = 2.52, p < 0.01) was significantly associated with premonitory urge.

CONCLUSION

Study results revealed three novel findings: adults with CTD experience increased anxiety-associated somatization and increased general body awareness relative to healthy controls; anxiety-associated somatization is more closely associated with sex and obsessive-compulsive symptoms than with CTD diagnosis; and increased general body awareness is associated with greater severity of premonitory urges.