Cooperation and depressive symptoms

Social decision-making in major depressive disorder: A three-level meta-analysis

Major Depressive Disorder (MDD) is frequently associated with social dysfunction and impaired decision-making, but its impact on social decisions remains unclear. Thus, we conducted a series of meta-analyses to examine the effects of MDD on key social decision phenomena, including trust, altruistic punishment, and cooperation. We searched Web of Science, PubMed, PsycINFO, and Embase up to December 2023, using Hedges' g to compare social decision-making between MDD patients and healthy controls (HCs). Meta-analytic results showed that MDD patients exhibited a significant reduction in trust (Hedges' g = -0.347, p < 0.001), no significant difference in altruistic punishment (Hedges' g = 0.232, p = 0.149), and an increase in cooperative behaviors (Hedges' g = 0.361, p = 0.002) compared to HCs. The moderation analysis revealed that age (p = 0.039) and region (p = 0.007) significantly moderated altruistic punishment, with older MDD patients and those from Asian and European regions having larger MDD-HC contrast than others. Regarding cooperation, moderation analysis indicated that age (p = 0.028), years of education (p = 0.054), and treatment coverage (p = 0.042) were significant moderators, indicating larger MDD-HC contrast in older, less-educated and better-treated people. These findings suggest MDD has different impacts on different social decisions, highlighting the need for fine-tuned therapeutic interventions that address these differences. The data also underscores the importance of considering demographic and treatment-related variables in managing MDD, which could inform personalized treatment strategies and improve social functionality and patient outcomes.

Impaired social learning in patients with major depressive disorder revealed by a reinforcement learning model

Background/objective

Patients with major depressive disorder (MDD) have altered learning rates for rewards and losses in non-social learning paradigms. However, it is not well understood whether the ability to learn from social interactions is altered in MDD patients. Using reinforcement learning during the repeated Trust Game (rTG), we investigated how MDD patients learn to trust newly-met partners in MDD patients.

Method

Sixty-eight MDD patients and fifty-four controls each played as 'investor' and interacted with ten different partners. We manipulated both the level of trustworthiness by varying the chance of reciprocity (10, 30, 50, 70 and 90%) and reputation disclosure, where partners' reputation was either pre-disclosed or hidden.

Results

Our reinforcement learning model revealed that MDD patients had significantly higher learning rates for losses than the controls in both the reputation disclosure and non-disclosure condition. The difference was larger when reputation was not disclosed than disclosed. We observed no difference in learning rates for gains in either condition.

Conclusions

Our findings highlight that abnormal learning for losses underlies the social learning process in MDD patients. This abnormality is higher when situational unpredictability is high versus low. Our findings provide novel insights into social rehabilitation of MDD.

Attention Towards Pupil Size in Humans and Bonobos (Pan paniscus)

Previous work has established that humans have an attentional bias towards emotional signals, and there is some evidence that this phenomenon is shared with bonobos, our closest relatives. Although many emotional signals are explicit and overt, implicit cues such as pupil size also contain emotional information for observers. Pupil size can impact social judgment and foster trust and social support, and is automatically mimicked, suggesting a communicative role. While an attentional bias towards more obvious emotional expressions has been shown, it is unclear whether this also extends to a more subtle implicit cue, like changes in pupil size. Therefore, the current study investigated whether attention is biased towards pupils of differing sizes in humans and bonobos. A total of 150 human participants (141 female), with a mean age of 19.13 (ranging from 18 to 32 years old), completed an online dot-probe task. Four female bonobos (6 to 17 years old) completed the dot-probe task presented via a touch screen. We used linear mixed multilevel models to examine the effect of pupil size on reaction times. In humans, our analysis showed a small but significant attentional bias towards dilated pupils compared to intermediate-sized pupils and intermediate-sized pupils when compared to small pupils. Our analysis did not show a significant effect in bonobos. These results suggest that the attentional bias towards emotions in humans can be extended to a subtle unconsciously produced signal, namely changes in pupil size. Due to methodological differences between the two experiments, more research is needed before drawing a conclusion regarding bonobos.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s42761-022-00146-1.

Differences in personality functioning impairment in mood, anxiety, and personality disorders: a cluster analysis

BACKGROUND

The Alternative DSM-5 Model for Personality Disorders and the latest eleventh version of the International Classification of Diseases implement the level of impairment in self and interpersonal personality functioning (Level of Personality Functioning Scale - LPFS) as a core feature of personality pathology. However, some studies have indicated that personality functioning is also impaired in other mental disorders, but a more thorough exploration is missing. Thus, this study aims to develop profiles of levels of personality functioning in people with personality disorders and some other psychiatric diagnoses as well as without diagnosis.

METHODS

One-hundred-forty-nine people participated in the study. They came from three groups - healthy controls (n = 53), people with personality disorders (n = 58), and people with mood and anxiety disorders (n = 38). The LPFS was assessed by the Semi-structured Interview for Personality Functioning DSM-5 (STiP-5.1). An optimal clustering solution using agglomerative hierarchical cluster analysis was generated to represent profiles of personality functioning.

RESULTS

The two patient groups showed significantly higher levels of personality functioning impairment than healthy controls. People with personality disorders showed higher levels of impairment than the other groups. In addition, the clustering analysis revealed three distinct profiles of personality functioning.

CONCLUSIONS

The impairment of personality functioning seems to be useful in the clinical assessment of other than personality disorders as well. As the resulting clustering profiles suggest, LPFS can be seen as an overall indicator of the severity of mental health difficulties and the presence of mental disorders symptoms. The LPFS provides valuable and detailed information about the individual's mental health and can thus serve as a broad basis for case formulation, treatment and therapy planning, and prognosis.

Interpersonal problems and cooperative behavior in patients suffering from prolonged grief disorder as compared to bereaved healthy controls

OBJECTIVES

Interpersonal factors, such as impairments in social interaction or lack of social support, have an important share when it comes to the development, maintenance, and progression of various mental disorders.

METHODS

Individuals suffering from prolonged grief disorder (PGD) and matched bereaved healthy controls (n = 54) underwent a thorough diagnostic procedure, further completed the Inventory of Interpersonal Problems (IIP-D-32), and participated in a finitely iterated prisoner's dilemma (FIPD).

RESULTS

Individuals suffering from PGD reported significantly more interpersonal problems. Both groups behaved differently in the FIPD with healthy controls being more carefully, adapting their behavior more flexible, whereas PGD patients displayed a lower responsiveness, which may indicate an inability to adapt to changes in relationships.

CONCLUSION

We conclude that interpersonal problems appear to be a relevant feature of PGD. Future studies need to clarify the causal relation behind this link, and should also include measures of attachment, social support, and disconnectedness.

Plasma acetylcholine and nicotinic acid are correlated with focused preference for photographed females in depressed males: an economic game study

Interpersonal difficulties are often observed in major depressive disorder (MDD), while the underlying psychological and biological mechanisms have not yet been elucidated. In the present case–control study, a PC-based trust game was conducted for 38 drug-free MDD patients and 38 healthy controls (HC). In the trust game, participants invested money in a partner (trusting behaviors), and also rated each partner’s attractiveness (preference for others). In addition, blood biomarkers including metabolites were measured. Both MDD and HC males exhibited more trusting behaviors compared to females. MDD males’ preference for ordinary-attractive partners (lay-person photographs) was lower than HC males, whereas their preference for high-attractive females (fashion-model photographs) was similar levels to HC males. This tendency in MDD males could reflect a “focused (narrowed) preference for females”. As for blood biomarker analysis, the levels of 37 metabolites including acetylcholine, AMP, GMP, nicotinic acid and tryptophan were significantly different between two groups. Interestingly, among male participants, acetylcholine and nicotinic acid were negatively correlated with the level of focused preference for photographed females. In sum, we have revealed some behavioral, psychological and biological traits of trusting behaviors and preference for others especially in MDD males. Larger studies should be conducted to validate our preliminary findings.

Work Stress and General Trust: The Mediating Effect of Depression and the Moderating Effect of the OXTR Gene rs53576

BACKGROUND

Work stress has been proved to be linked to depression, and both can decrease general trust. Likewise, OXTR gene is currently the gene that is most closely associated with trust. However, few empirical studies have explored the significant role of gene-environment interactions on general trust. In this study, we explored the mediating role of depression in the relationship between work stress and general trust, and the moderating role of the OXTR rs 53576 in the mediation model.

METHODS

364 healthy Han Chinese faculties were recruited from one university in Beijing. Work stress, depression, and general trust were assessed using the House and Rizzo's Work Stress Scale, Self-Rating Depression Scale (SDS), and the General Trust Questionnaire, respectively. Blood samples were collected for OXTR rs53576 genotyping.

RESULTS

Depression mediated the relationship between work stress and general trust. In the mediation model, OXTR rs53576 could only moderated the direct path from work stress to general trust. For AA and GA individuals, depression completely mediated the relationship between work stress and general trust. For GG individuals, depression partly mediated the relationship between work stress and general trust.

LIMITATIONS

This study used a cross-sectional design, only considered Han Chinese faculties, and the role of other genes should be explored.

CONCLUSIONS

Depression has a mediating effect between work stress and general trust. The general trust levels of GG genotype individuals are more prone to be affected by work stress than AA and GA individuals.

Contribution of religion/spirituality and major depressive disorder to altruism

BACKGROUND

In most studies, religiosity and spirituality (R/S) are positively associated with altruism, whereas depression is negatively associated. However, the cross-sectional designs of these studies limit their epidemiological value. We examine the association of R/S and major depressive disorder (MDD) with altruism in a five year longitudinal study nested in a larger prospective study.

METHODS

Depressed and non-depressed individuals and their first- and second-generation offspring were assessed over several decades. At Year30 after baseline, R/S was measured using participants' self-report; MDD, by clinical interview. At Year35, participants completed a measure of altruism. Adjusted odds ratios (AOR) were calculated using multivariate logistic regression; statistical significance, set at p<.05. two-tailed.

RESULTS

In the overall sample, both R/S and MDD were significantly associated with altruism, AOR 2.52 (95% CI 1.15-5.49) and AOR 2.43 (95% CI 1.05-5.64), respectively; in the High Risk group alone, the corresponding AORs were 4.69 (95% CI 1.39-15.84) and 4.74 (95% CI 1.92-11.72). Among highly R/S people in the High Risk group, the AOR for MDD with altruism was 22.55 (95% CI 1.23-414.60) p<.04; among the remainder, it was 3.12 (95% CI 0.63-15.30), a substantial but non-significant difference.

LIMITATIONS

Altruism is based on self-report, not observation, hence, vulnerable to bias.

CONCLUSIONS

MDD's positive association with elevated altruism concurs with studies of posttraumatic growth in finding developmental growth from adversity. The conditions that foster MDD's positive association with altruism and the contribution of R/S to this process requires further study.

A review of neuroeconomic gameplay in psychiatric disorders

Abnormalities in social interaction are a common feature of several psychiatric disorders, aligning with the recent move towards using Research Domain Criteria (RDoC) to describe disorders in terms of observable behaviours rather than using specific diagnoses. Neuroeconomic games are an effective measure of social decision-making that can be adapted for use in neuroimaging, allowing investigation of the biological basis for behaviour. This review summarises findings of neuroeconomic gameplay studies in Axis 1 psychiatric disorders and advocates the use of these games as measures of the RDoC Affiliation and Attachment, Reward Responsiveness, Reward Learning and Reward Valuation constructs. Although research on neuroeconomic gameplay is in its infancy, consistencies have been observed across disorders, particularly in terms of impaired integration of social and cognitive information, avoidance of negative social interactions and reduced reward sensitivity, as well as a reduction in activity in brain regions associated with processing and responding to social information.

Depressive adolescent girls exhibit atypical social decision-making in an iterative trust game

INTRODUCTION

Interpersonal trust behavior is an important target for the identification and treatment of psychiatric disorders with interpersonal dysfunction. Adolescent depression is a highly interpersonal disorder marked by impaired social interactions. However, trust has received little empirical attention. The examination of reward-related decision-making using behavioral economic methods is a relatively novel approach for studying trust in adolescent depression. The present study employed a modified trust game to examine whether depressive adolescents exhibited perturbed reward-related decision-making in social and/or nonsocial contexts.

METHODS

One-hundred and thirty adolescent girls (65 depressive, 65 healthy comparisons) played a modified trust game under two conditions, interpersonal risk-taking (trust) and general risk-taking (lottery), and completed self-report psychopathology measures.

RESULTS

Three-way repeated measures ANCOVA analyses revealed a significant group x game interaction such that while the depressive group invested more across trials in the trust game they invested similarly to healthy comparisons in the lottery condition.

DISCUSSION

Findings highlight the interpersonal nature of adolescent depression. Future research may help determine whether increased trust behavior is characteristic of depression in adolescent girls. Behavioral economic games, like the trust game, may serve as valuable therapeutic tools for improving social interaction style among depressive adolescents.

Cooperation and sensitivity to social feedback during group interactions in schizophrenia

Patients with schizophrenia show reduced cooperation and less sensitivity to social cues in pairwise interactions, however, it remains unclear whether these mechanisms are also present in interactions within social groups. We used a public goods game to investigate cooperation and sensitivity to social feedback in group interactions in 27 patients with schizophrenia and 27 healthy controls. Participants played 40 trials in two conditions: 1) no fine (20 trials): participants had the choice of investing into the public good (i.e. cooperating) or not (i.e. defecting), 2) fine (20 trials): participants had the same choice but defectors could be punished by the other players. On the first trial, patients invested less in the public good than healthy controls. In the no fine condition, controls decreased their investments over time, but patients did not. The possibility of being fined for defecting and actually being fined led to significantly higher cooperation in both groups. This shows that the groups were equally sensitive to social enforcement and social feedback. Our findings suggest that patients tend to approach social group interactions with less cooperative behaviour, which could contribute to social dysfunction in daily-life. However, an intact sensitivity to social enforcement and feedback indicates that patients can adjust their behaviour accordingly in group interactions.

Getting less than their fair share: Maltreated youth are hyper-cooperative yet vulnerable to exploitation in a public goods game

Human cooperative behavior has long been thought to decline under adversity. However, studies have primarily examined perceived patterns of cooperation, with little eye to actual cooperative behavior embedded within social interaction. Game-theoretical paradigms can help close this gap by unpacking subtle differences in how cooperation unfolds during initial encounters. This study is the first to use a child-appropriate, virtual, public goods game to study actual cooperative behavior in 329 participants aged 9-16 years with histories of maltreatment (n = 99) and no maltreatment (n = 230) while controlling for psychiatric symptoms. Unlike work on perceived patterns of cooperation, we found that maltreated participants actually contribute more resources to a public good during peer interaction than their nonmaltreated counterparts. This effect was robust when controlling for psychiatric symptoms and peer problems as well as demographic variables. We conclude that maltreatment may engender a hyper-cooperative strategy to minimize the odds of hostility and preserve positive interaction during initial encounters. This, however, comes at the cost of potential exploitation by others.

Predicting post treatment client satisfaction between behavioural activation for depression delivered either in-person or via home-based telehealth

Introduction

Treatment engagement, adherence, cancellations and other patient-centric data are important predictors of treatment outcome. But often these data are only examined retrospectively. In this investigation, we analysed data from a clinical trial focused on innovative delivery of depression treatment to identify which patients are likely to prefer either in-home or in-person treatment based on pre-treatment characteristics.

Methods

Patient satisfaction was assessed in a trial of individuals with depression treated using identical behavioural activation therapy protocols in person or through videoconferencing to the home ( N = 87 at post treatment: 42 in-person and 45 in-home participants). The Client Satisfaction Questionnaire was administered at the end of the treatment. A Tobit regression model was used to assess moderation using treatment assignment. Regression lines were generated to model treatment satisfaction as a function of treatment assignment and to identify whether and where the groups intersected. We examined the distributions of the contributing moderators to the subsets of participants above and below the intersection point to identify differences.

Results

While no significant differences in patient satisfaction were observed between the two groups, or between patients receiving treatment by different providers, baseline characteristics of the sample could be used to differentiate those with a preference for traditional, in-office care from those preferring in-home care.

Discussion

Participants who were more likely to prefer in-home care were characterized by larger proportions of veterans and lower-ranked enlisted service members. They also had more severe symptoms at baseline and less formal education. Understanding client reactions when selecting treatment modality may allow for a more satisfying patient experience.

Quantitative account of social interactions in a mental health care ecosystem: cooperation, trust and collective action

Mental disorders have an enormous impact in our society, both in personal terms and in the economic costs associated with their treatment. In order to scale up services and bring down costs, administrations are starting to promote social interactions as key to care provision. We analyze quantitatively the importance of communities for effective mental health care, considering all community members involved. By means of citizen science practices, we have designed a suite of games that allow to probe into different behavioral traits of the role groups of the ecosystem. The evidence reinforces the idea of community social capital, with caregivers and professionals playing a leading role. Yet, the cost of collective action is mainly supported by individuals with a mental condition - which unveils their vulnerability. The results are in general agreement with previous findings but, since we broaden the perspective of previous studies, we are also able to find marked differences in the social behavior of certain groups of mental disorders. We finally point to the conditions under which cooperation among members of the ecosystem is better sustained, suggesting how virtuous cycles of inclusion and participation can be promoted in a 'care in the community' framework.

Pupil mimicry and trust - Implication for depression

Individuals suffering from depression often have difficulty trusting others. Previous research has shown a relationship between trust formation and pupil mimicry - the synchronization of pupil sizes between individuals. The current study therefore examined whether pupil mimicry is weaker in depressed individuals and an underlying factor of their low levels of trust. Forty-two patients with major depressive disorder (MDD) and 40 healthy control subjects played trust games with virtual partners. Images of these partners' eye regions were presented to participants before they had to make a monetary investment decision. Partners' pupils either dilated, constricted, or remained static over the course of 4-s interactions. During the task, participants' pupil sizes were recorded with eye-tracking equipment to assess mimicry. The results confirm that patients with MDD were somewhat less trusting than controls and used another's pupillary cues differently when deciding to trust. Specifically, whereas healthy controls trusted partners with dilating pupils more than partners with constricting pupils, patients with MDD particularly trusted partners whose pupils changed in size less, regardless of whether partners' pupils were dilating or constricting. This difference in investment behavior was unrelated to differences in pupil mimicry, which was equally apparent in both groups and fostered trust to the same extent. Whereas lower levels of trust observed in patients with MDD could not be explained by differences in pupil mimicry, our data show that pupil dilation mimicry might help people to trust. These findings provide further evidence for the important role of pupil size and pupil mimicry in interpersonal trust formation and shed light on the pathophysiology of clinically low trust in patients with MDD.

Cooperative Behavior in the Ultimatum Game and Prisoner's Dilemma Depends on Players' Contributions

Economic games such as the Ultimatum Game (UG) and Prisoner's Dilemma (PD) are widely used paradigms for studying fairness and cooperation. Monetary versions of these games involve two players splitting an arbitrary sum of money. In real life, however, people's propensity to engage in cooperative behavior depends on their effort and contribution; factors that are well known to affect perceptions of fairness. We therefore sought to explore the impact of relative monetary contributions by players in the UG and PD. Adapted computerized UG and PD games, in which relative contributions from each player were manipulated, were administered to 200 participants aged 18-50 years old (50% female). We found that players' contribution had large effects on cooperative behavior. Specifically, cooperation was greater amongst participants when their opponent had contributed more to joint earnings. This was manifested as higher acceptance rates and higher offers in the UG; and fewer defects in the PD compared to when the participant contributed more. Interestingly, equal contributions elicited the greatest sensitivity to fairness in the UG, and least frequent defection in the PD. Acceptance rates correlated positively with anxiety and sex differences were found in defection behavior. This study highlights the feasibility of computerized games to assess cooperative behavior and the importance of considering cooperation within the context of effortful contribution.

Prosocial Behavior and Depression: a Case for Developmental Gender Differences

Purpose of Review

Prosocial behavior and depression are related constructs that both increase during adolescence and display gender-specific effects. The current review surveys literature examining the association between depressive symptoms and prosociality, measured with behavioral economic paradigms, across development and proposes a theoretical model explaining a mechanism through which adolescent girls have higher risk for depression than boys.

Recent Findings

Relative to healthy controls, prosocial behavior is reduced in adults with major depressive disorder (MDD) but may be increased in adolescents with MDD. The relationship between non-clinical levels of depressive symptoms and prosocial behavior remains to be studied experimentally; however, self-reported prosocial behavior is negatively associated with depressive symptoms in non-clinical adolescents, which may suggest a shift in the relation of prosocial behavior and depressive symptoms across the non-clinical (i.e., negative) to clinical range (i.e., positive).

Summary

The effect of gender on these developmental and clinical status shifts has not been studied but could have important implications for understanding the emergence of higher rates of depression in girls than boys during adolescence. We propose that girls are at heightened risk for depression due to higher social-evaluative concern and other-oriented prosocial motivation that emphasize the needs of others over the self, leading to more altruistic prosocial behavior (despite personal cost) and a higher burden that enables depressive symptoms.

The influence of cooperation and defection on social decision making in depression: A study of the iterated Prisoner's Dilemma Game

This study evaluated the influence of self-reported levels of depression on interpersonal strategic decision making when interacting with partners who differed in their predetermined tendency to cooperate in three separate computerized iterated Prisoner's Dilemma Games (iPDGs). Across 29 participants, cooperation was lowest when interacting with a predominantly defecting partner and highest when interacting with a predominantly cooperating partner. Greater depression severity was related to steadier and continued cooperation over trials with the cooperating partner, seeming to reflect a prosocial response tendency when interacting with this partner. With the unbiased partner, depression severity was associated with a more volatile response pattern in reaction to cooperation and defection by this partner. Severity of depression did not influence cooperation with a defecting partner or expectations about partner cooperation reported before the task began. Taken together, these data appear to show that in predominately positive interactions, as in the cooperating partner condition, depression is associated with less volatile, more consistent cooperation. When such clear feedback is absent, as in the unbiased partner condition, depression is associated with more volatile behavior. Nonetheless, participants were generally able to adapt their behavior accordingly in this dynamic interpersonal decision making context.

Social functioning in major depressive disorder

Depression is associated with social risk factors, social impairments and poor social functioning. This paper gives an overview of these social aspects using the NIMH Research and Domain Criteria 'Systems for Social Processes' as a framework. In particular, it describes the bio-psycho-social interplay regarding impaired affiliation and attachment (social anhedonia, hyper-sensitivity to social rejection, competition avoidance, increased altruistic punishment), impaired social communication (impaired emotion recognition, diminished cooperativeness), impaired social perception (reduced empathy, theory-of-mind deficits) and their impact on social networks and the use of social media. It describes these dysfunctional social processes at the behavioural, neuroanatomical, neurochemical and genetic levels, and with respect to animal models of social stress. We discuss the diagnostic specificity of these social deficit constructs for depression and in relation to depression severity. Since social factors are importantly involved in the pathogenesis and the consequences of depression, such research will likely contribute to better diagnostic assessments and concepts, treatments and preventative strategies both at the diagnostic and transdiagnostic level.

Testing the social competition hypothesis of depression using a simple economic game

BACKGROUND

Price's social competition hypothesis interprets the depressive state as an unconscious, involuntary losing strategy, which enables individuals to yield and accept defeat in competitive situations.

AIMS

We investigated whether patients who suffer from major depressive disorder (MDD) would avoid competition more often than either patients suffering from borderline personality disorder (BPD) or healthy controls.

METHOD

In a simple paper-folding task healthy participants and patiens with MDD and BPD were matched with two opponents, one with an unknown diagnosis and one who shared their clinical diagnosis, and they had to choose either a competitive or cooperative payment scheme for task completion.

RESULTS

When playing against an unknown opponent, but not the opponent with the same diagnosis, the patients with depression chose the competitive payment scheme statistically less often than healthy controls and patients diagnosed with BPD.

CONCLUSION

The competition avoidance against the unknown opponent is consistent with Price's social competition hypothesis.

DECLARATION OF INTEREST

G.H. received research support, consulting fees and speaker honoraria from Lundbeck, AstraZeneca, Servier, Eli Lilly, Roche and Novartis.

COPYRIGHT AND USAGE

© The Royal College of Psychiatrists 2016. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) licence.

Oxytocin Conditions Intergroup Relations Through Upregulated In-Group Empathy, Cooperation, Conformity, and Defense

Humans live in, rely on, and contribute to groups. Evolution may have biologically prepared them to quickly identify others as belonging to the in-group (vs. not), to decode emotional states, and to empathize with in-group members; to learn and conform to group norms and cultural practices; to extend and reciprocate trust and cooperation; and to aggressively protect the in-group against outside threat. We review evidence that these components of human group psychology rest on and are modulated by the hypothalamic neuropeptide oxytocin. It appears that oxytocin motivates and enables humans to 1) like and empathize with others in their groups, 2) comply with group norms and cultural practices, and 3) extend and reciprocate trust and cooperation, which may give rise to intergroup discrimination and sometimes defensive aggression against threatening (members of) out-groups. We explore the possibility that deficiencies in (components of) group psychology, seen in autistic spectrum disorder, schizophrenia, and borderline personality and social anxiety disorders, may be reduced by oxytocin administration. Avenues for new research are highlighted, and implications for the role of oxytocin in cooperation and competition within and between groups are discussed.

Multidimensional anatomy of 'modern type depression' in Japan: A proposal for a different diagnostic approach to depression beyond the DSM-5

Japan's prototype of depression was traditionally a melancholic depression based on the premorbid personality known as shūchaku-kishitsu proposed by Mitsuzo Shimoda in the 1930s. However, since around 2000, a novel form of depression has emerged among Japanese youth. Called 'modern type depression (MTD)' by the mass media, the term has quickly gained popularity among the general public, though it has not been regarded as an official medical term. Likewise, lack of consensus guidelines for its diagnosis and treatment, and a dearth of scientific literature on MTD has led to confusion when dealing with it in clinical practice in Japan. In this review article, we summarize and discuss the present situation and issues regarding MTD by focusing on historical, diagnostic, psychosocial, and cultural perspectives. We also draw on international perspectives that begin to suggest that MTD is a phenomenon that may exist not only in Japan but also in many other countries with different sociocultural and historical backgrounds. It is therefore of interest to establish whether MTD is a culture-specific phenomenon in Japan or a syndrome that can be classified using international diagnostic criteria as contained in the ICD or the DSM. We propose a novel diagnostic approach for depression that addresses MTD in order to combat the current confusion about depression under the present diagnostic systems.

Game Theory Paradigm: A New Tool for Investigating Social Dysfunction in Major Depressive Disorders

Social dysfunction is a prominent source of distress and disability in patients with major depressive disorder (MDD) but is commonly omitted from current clinical studies, although some researchers propose an evolutionary strategy to understand these negative outcomes. Limited knowledge about the neural basis of social dysfunction in MDD results from traditional paradigms, which lack insights into social interactions. Game theoretical modeling offers a new tool for investigating social-interaction impairments in neuropsychiatric disorders. This review first introduces three widely used games from game theory and the major behavioral and neuroimaging findings obtained using these games in healthy populations. We also address the factors that modulate behaviors in games and their neural bases. We then summarize the current findings obtained by using these games in depressed patients and discuss the clinical implications of these abnormal game behaviors. Finally, we briefly discuss future prospects that may further elucidate the clinical use of a game theory paradigm in MDD.

Relationship between trusting behaviors and psychometrics associated with social network and depression among young generation: a pilot study

Maladaptive social interaction and its related psychopathology have been highlighted in psychiatry especially among younger generations. In Japan, novel expressive forms of psychiatric phenomena such as "modern-type depression" and "hikikomori" (a syndrome of severe social withdrawal lasting for at least six months) have been reported especially among young people. Economic games such as the trust game have been utilized to evaluate real-world interpersonal relationships as a novel candidate for psychiatric evaluations. To investigate the relationship between trusting behaviors and various psychometric scales, we conducted a trust game experiment with eighty-one Japanese university students as a pilot study. Participants made a risky financial decision about whether to trust each of 40 photographed partners. Participants then answered a set of questionnaires with seven scales including the Lubben Social Network Scale (LSNS)-6 and the Patient Health Questionnaire (PHQ)-9. Consistent with previous research, male participants trusted partners more than female participants. Regression analysis revealed that LSNS-family (perceived support from family) for male participants, and item 8 of PHQ-9 (subjective agitation and/or retardation) for female participants were associated with participants' trusting behaviors. Consistent with claims by social scientists, our data suggest that, for males, support from family was negatively associated with cooperative behavior toward non-family members. Females with higher subjective agitation (and/or retardation) gave less money toward males and high attractive females, but not toward low attractive females in interpersonal relationships. We believe that our data indicate the possible impact of economic games in psychiatric research and clinical practice, and validation in clinical samples including modern-type depression and hikikomori should be investigated.