Endogenous oxytocin response to film scenes of attachment and loss is pronounced in schizophrenia

From Oxytocin to Compassion: The Saliency of Distress

Compassion is a warm response of care and concern for those who are suffering, which drives individuals to devote their resources for the sake of others. A prominent neuroevolutionary framework grounds compassion in the neurobiology of the mammalian caregiving system. Accordingly, it has been suggested that the oxytocinergic system, which plays a central role in parental caregiving and bonding, provides the neurobiological foundation for compassion towards strangers. Yet, the specific role of oxytocin in compassion is far from clear. The current paper aims to target this gap and offer a theoretical framework that integrates the state-of-the-art literature on oxytocin with research on compassion. We suggest that oxytocin mediates compassion by enhancing the saliency of cues of pain and distress and discuss the plausible underlying neurobiological substrates. We further demonstrate how the proposed framework can account for individual differences in compassion, focusing on the effects of attachment on caregiving and support. The proposed framework integrates the current scientific understanding of oxytocin function with compassion-related processes. It thus highlights the largely ignored attentional processes in compassion and taps into the vast variability of responses in social contexts involving pain and suffering.

Oxytocin: An Old Hormone, A Novel Psychotropic Drug And Possible Use In Treating Psychiatric Disorders

BACKGROUND

Oxytocin is a nonapeptide synthesized in the paraventricular and supraoptic nuclei of the hypothalamus. Historically, this molecule has been involved as a key factor in the formation of infant attachment, maternal behavior and pair bonding and, more generally, in linking social signals with cognition, behaviors and reward. In the last decades, the whole oxytocin system has gained a growing interest as it was proposed to be implicated in etiopathogenesis of several neurodevelopmental and neuropsychiatric disorders.

METHODS

With the main goal of an in-depth understanding of the oxytocin role in the regulation of different functions and complex behaviors as well as its intriguing implications in different neuropsychiatric disorders, we performed a critical review of the current state of art. We carried out this work through PubMed database up to June 2021 with the search terms: 1) "oxytocin and neuropsychiatric disorders"; 2) "oxytocin and neurodevelopmental disorders"; 3) "oxytocin and anorexia"; 4) "oxytocin and eating disorders"; 5) "oxytocin and obsessive-compulsive disorder"; 6) "oxytocin and schizophrenia"; 7) "oxytocin and depression"; 8) "oxytocin and bipolar disorder"; 9) "oxytocin and psychosis"; 10) "oxytocin and anxiety"; 11) "oxytocin and personality disorder"; 12) "oxytocin and PTSD".

RESULTS

Biological, genetic, and epigenetic studies highlighted quality and quantity modifications in the expression of oxytocin peptide or in oxytocin receptor isoforms. These alterations would seem to be correlated with a higher risk of presenting several neuropsychiatric disorders belonging to different psychopathological spectra. Collaterally, the exogenous oxytocin administration has shown to ameliorate many neuropsychiatric clinical conditions.

CONCLUSION

Finally, we briefly analyzed the potential pharmacological use of oxytocin in patient with severe symptomatic SARS-CoV-2 infection due to its anti-inflammatory, anti-oxidative and immunoregulatory properties.

Peripheral oxytocin concentrations in psychiatric disorders - A systematic review and methanalysis: Further evidence

Increased interest in understanding how changes in the oxytocinergic system are associated with the etiology and progression of psychiatric disorders has currently boosted the publication of studies. We present a systematic literature review followed by meta-analyses assessing whether peripheral oxytocin (OXT) levels among psychiatric patients differ from healthy controls, considering the moderating role of methodological aspects and samples' characteristics. The following electronic databases were searched: PubMed, Web of Science, PsycINFO, SciELO, LILACS, and Scopus. Fifty-five papers were included in the analysis, and nine independent meta-analyses were performed according to the different diagnoses. Lower OXT concentrations were found in groups of specific disorders (i.e., schizophrenia, restricting and binge-eating/purging subtypes of anorexia nervosa, and borderline personality disorder) with medium to large effect sizes. Great heterogeneity was found among the studies, so that caution is needed to interpret the results. High OXT levels with an effect size of the same magnitude were found for bipolar disorder - type I and obsessive disorder. In contrast, no differences were found for bulimia, autism spectrum, depression, or social anxiety. No meta-analyses were performed for body dysmorphic disorder, post-traumatic stress disorder, or trichotillomania because only one study was identified for each of these disorders. Altered endogenous OXT concentrations are found in several disorders addressed and must be analyzed according to each disorder's specificities.

Insecure attachment as a transdiagnostic risk factor for major psychiatric conditions: A meta-analysis in bipolar disorder, depression and schizophrenia spectrum disorder

Insecure attachment has been suggested as a major risk factor for mental health problems as well as a key element for the development and trajectory of psychiatric disorders. The aim of this meta-analysis was to assess whether insecure attachment constitutes a global transdiagnostic risk factor in bipolar disorder, depression, and schizophrenia spectrum disorders. We conducted a PRISMA-based systematic quantitative review to explore the prevalence of insecure attachment among patients of three representative psychiatric disorders - major depression, schizophrenia spectrum disorders and bipolar disorder - in comparison with healthy controls (HC) from a transdiagnostic point of view. Effect sizes on differences of anxious, avoidant and insecure prevalence were calculated based on 40 samples including a total of n = 2927 individuals. Overall, results indicated a large effect on prevalence of insecure attachment across all disorders compared to HC (k = 30, g = 0.88, I² = 71.0%, p < 0.001). In a transdiagnostic comparison, the only difference was found in avoidant attachment, which was significantly lower (p = 0.04) compared to HC in the schizophrenia spectrum disorder subgroup (k = 10, g = 0.31, I² = 76.60%, p < 0.0001) than the depression subgroup subgroup (k = 12, g = 0.83, I² = 46.65%, p < 0.0001). The lack of further transdiagnostic differences between three distinct psychiatric disorders corroborates insecure attachment as a general vulnerability factor to psychopathology. Our findings warrant further investigations, which should explore the pathways from attachment insecurity towards psychopathology. Insecure attachment likely has implications on assessment, prediction and treatment of psychiatric patients.

Oxytocin levels in individuals with schizophrenia are high in cerebrospinal fluid but low in serum: A systematic review and meta-analysis : Oxytocin and Schizophrenia

Schizophrenia is a debilitating mental illness. Levels of oxytocin have been proposed as a biomarker of schizophrenia; however, the observed levels of oxytocin in individuals with schizophrenia have been inconsistent across studies. We performed a meta-analysis to evaluate oxytocin levels in plasma, serum and cerebrospinal fluid to see if there are statistically different concentrations between individuals with schizophrenia and the comparison group. The meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Following the inclusion and exclusion criteria, 14 studies were included in the meta-analysis. The quality of the study was evaluated by the Newcastle-Ottawa Scale (NOS). A random-effects model was performed using the Comprehensive Meta-analysis software with the standardized mean difference (SMD) and 95% confidence intervals (CIs). Serum oxytocin levels in individuals with schizophrenia were significantly lower than that in comparison group (SMD =  - 1.74, 95% CI =  - 3.22 to - 0.26, p = 0.02) but cerebrospinal fluid oxytocin levels in individuals with schizophrenia were significantly higher than those in the comparison group (SMD = 0.55, 95% CI = 0.05 to 1.04, p = 0.03). Our results suggest that oxytocin levels in cerebrospinal fluid are increased in individuals with schizophrenia but decreased in serum. Therefore, the oxytocin system dysregulation may play a role in the pathophysiology of schizophrenia and it should be measured in more populations for a possible implementation as a biomarker of schizophrenia.

Attachment Dimensions predict Social Functioning in persons with Schizophrenia-Spectrum Disorders, regardless of Symptom Severity

Attachment patterns and early-life adversities are relevant to understand the role of psychosocial factors in the vulnerability and the development of psychosis. The first aim of the study was to test whether a dimensional attachment instrument, the CAMIR (from French; Cartes: Modèles Individuels de Relation), may differentiate attachment styles by comparing a group of psychotic patients with a non-clinical sample. Also, we hypothesised that attachment dimensions would predict Social Functioning (SF) within the clinical group.

Being moved by listening to unfamiliar sad music induces reward-related hormonal changes in empathic listeners

Many people enjoy sad music, and the appeal for tragedy is widespread among the consumers of film and literature. The underlying mechanisms of such aesthetic experiences are not well understood. We tested whether pleasure induced by sad, unfamiliar instrumental music is explained with a homeostatic or a reward theory, each of which is associated with opposite patterns of changes in the key hormones. Sixty-two women listened to sad music (or nothing) while serum was collected for subsequent measurement of prolactin (PRL) and oxytocin (OT) and stress marker (cortisol and adrenocorticotropic hormone) concentrations. Two groups of participants were recruited on the basis of low and high trait empathy. In the high empathy group, PRL and OT levels were significantly lower with music compared with no music. And compared to the low empathy group, the high empathy individuals reported an increase of positive mood and higher ratings of being moved with music. None of the stress markers showed any changes across the conditions or the groups. These hormonal changes, inconsistent with the homeostatic theory proposed by Huron, exhibit a pattern expected of general reward. Our findings illuminate how unfamiliar and low arousal music may give rise to pleasurable experiences.

Oxytocin in Schizophrenia: Pathophysiology and Implications for Future Treatment

Schizophrenia is a form of mental disorder that is behaviorally characterized by abnormal behavior, such as social function deficits or other behaviors that are disconnected from reality. Dysregulation of oxytocin may play a role in regulating the expression of schizophrenia. Given oxytocin’s role in social cognition and behavior, a variety of studies have examined the potential clinical benefits of oxytocin in improving the psychopathology of patients with schizophrenia. In this review, we highlight the evidence for the role of endogenous oxytocin in schizophrenia, from animal models to human studies. We further discuss the potential of oxytocin as a therapeutic agent for schizophrenia and its implication in future treatment.

Peripheral oxytocin is inversely correlated with cognitive, but not emotional empathy in schizophrenia

Endogenous oxytocin has been associated with different aspects of social cognition in healthy subjects and patients with schizophrenia. In this pilot study, we investigated the relationship between plasma oxytocin and oxytocin level changes induced by empathy-eliciting, attachment-related movie scenes with correlates of cognitive and emotional empathy in patients and healthy controls. The Multifaceted Empathy Test (MET) and the Interpersonal Reactivity Index (IRI) were administered to patients with schizophrenia (N = 35, 12 females) and healthy controls (N = 35, 12 females) to estimate dimensions of cognitive and emotional empathy. Peripheral basal oxytocin concentrations and oxytocin responses to movie-based emotional stimuli were assessed using radioimmunoassay with sample extraction. In patients, induced oxytocin level changes were inversely correlated with MET cognitive empathy regarding negative emotional states. Controlling for non-social cognition and age revealed a significant negative association between basal oxytocin levels and MET cognitive empathy for positive emotions. In healthy subjects, oxytocin reactivity was inversely correlated with the IRI subscale "fantasy". Oxytocin was not related to any measure of emotional empathy. A hyper-reactive oxytocin system might be linked to impaired cognitive empathy as a part of a dysfunctional regulative circuit of attachment-related emotions and interpersonal stressors or threats by attribution of meaning. Healthy adults with a disposition to identify with fictional characters showed lower oxytocin reactivity, possibly indicating familiarity with movie-based stimuli. The oxytocinergic system may be involved in maladaptive coping mechanisms in the framework of impaired mentalizing and associated dysfunctional responses to interpersonal challenges in schizophrenia.