国際誌論文データベース

Kido, Y., (貴堂雄太) & Takezawa, M. (竹澤正哲) (2024). 
Coevolution of norm psychology and cooperation through exapted conformity.
外適応した多数派同調傾向による規範心理と協力の共進化
Evolutionary Human Sciences, 6, e35.
http://dx.doi.org/10.1017/ehs.2024.37

People willingly follow norms and values, often incurring material costs. This behaviour supposedly stems from evolved norm psychology, contributing to large-scale cooperation among humans. It has been argued that cooperation is influenced by two types of norms: injunctive and descriptive. This study theoretically explores the socialisation of humans under these norms. Our agent-based model simulates scenarios where diverse agents with heterogeneous norm psychologies engage in collective action to maximise their utility functions that capture three motives: gaining material payoff, following injunctive and descriptive norms. Multilevel selective pressure drives the evolution of norm psychology that affects the utility function. Further, we develop a model with exapted conformity, assuming selective advantage for descriptive norm psychology. We show that norm psychology can evolve via cultural group selection. We then identify two normative conditions that favour the evolution of norm psychology, and therefore cooperation: injunctive norms promoting punitive behaviour and descriptive norms. Furthermore, we delineate different characteristics of cooperative societies under these two conditions and explore the potential for a macro transition between them. Together, our results validate the emergence of large-scale cooperative societies through social norms and suggest complementary roles that conformity and punishment play in human prosociality.

Shimizu, Y.(清水佑輔), Kudo, Y.(工藤泰幸), & Karasawa, K.(唐沢かおり) (2024). 
Are older adults perceived as morally better than middle-aged persons? Focus on the stereotype content model.
高齢者は中年よりも道徳的に善いと認知されているのか：ステレオタイプ内容モデルに着目して
Acta Psychologica, 251, 104584.
https://doi.org/10.1016/j.actpsy.2024.104584

Identifying and improving existing morality perceptions regarding older adults is crucial for fostering intergenerational cooperation and constructing an inclusive society. In this study, we conducted two online experiments with Japanese participants to investigate the degrees to which older adults are perceived as moral. We predicted that older adults are more likely to be perceived as morally good compared to middle-aged individuals (Hypothesis 1), and that regardless of the target person’s age, individuals perceived as warm (Hypothesis 2) and competent (Hypothesis 3) are more likely to be regarded as morally good. In Study 1, participants were instructed to freely describe a typical older (aged 80 years) or middle-aged (aged 50 years) target individual. Contrary to expectations, the middle-aged target individual was perceived as morally better than the older counterpart. Meanwhile, regardless of the target individual’s age, the target individuals perceived as warm and competent were more likely to be viewed as morally good. In Study 2, participants were presented with a simple vignette describing an older (aged 80 years) or middle-aged (aged 50 years) target individual, manipulating their warmth (warm/cold) and competence (competent/incompetent). The results indicated no effect of target age on moral perceptions, but warmer and/or more competent target individuals elicited higher moral perceptions. Thus, Hypothesis 1 was not supported in either study, whereas Hypotheses 2 and 3 were supported across both studies. These findings underscore the importance of enhancing moral perceptions, warmth, and competence regarding older adults to facilitate appropriate assistance from other generations.

Asano, R.（浅野良輔）, Kanemasa, Y.（金政祐司）, Komura, K.（古村健太郎）, & Ito, K. (2024)
The interdependent nature of well-being: Evidence from American and Japanese spouses. 
幸福感の相互依存性：米国と日本の夫婦データによる検討
Personality and Social Psychology Bulletin. Advance online publication.
https://doi.org/10.1177/01461672241285180

The present study investigated spousal interdependencies in well-being and the sources of these interdependencies among Americans and Japanese. We collected high-powered three-wave longitudinal and cross-sectional data from a wide age range of participants (Ns = 3,012 American couples aged 26–96 and 2,307 Japanese couples aged 24–76) and assessed a variety of well-being measures. Study 1 replicated previous findings that American spouses’ well-being was positively associated with each other. Studies 2a and 2b generalized the findings of Study 1 to Japanese spouses. Both Studies 1 and 2b showed conflicting results: There were effects of mutual influence and shared environmental factors’ influences on American and Japanese spouses’ well-being in a longitudinal actor-partner interdependence model when using the cross-lagged panel model, but not when using the random intercept cross-lagged panel model. These findings illustrate that the interdependent nature of well-being is an essential feature of American and Japanese married couples.

米国人の縦断的夫婦データと日本人の横断的・縦断的夫婦データを用いて、幸福感が配偶者間で関連しているかどうかを検討しました。米国人・日本人ともに、先行研究に基づいた縦断データ分析（CLPM）を行うと同様の結果が得られた一方で、新たな縦断データ分析（RI-CLPM）を行うと異なる結果が得られたのが特徴です。

Yamamoto, H.(山本仁志), Okada, I.(岡田勇), Sasaki, T., & Uchida, S. (2024).
Clarifying social norms which have robustness against reputation costs and defector invasion in indirect reciprocity.
間接互恵性における評判コストと非協力者に対する頑健性を持つ社会的規範の解明
Scientific Reports, 14(1), 25073.
https://doi.org/10.1038/s41598-024-76168-5

The evolution of cooperation through indirect reciprocity is a pivotal mechanism for sustaining large-scale societies. Because third parties return cooperative behaviour in indirect reciprocity, reputations that assess and share these third parties’ behaviour play an essential role. Studies on indirect reciprocity have predominantly focused on the costs associated with cooperative behaviour, overlooking the costs tied to the mechanisms underpinning reputation sharing. Here, we explore the robustness of social norms necessary to secure the stability of indirect reciprocity, considering both the costs of reputation and the resilience against perfect defectors. Firstly, our results replicate that only eight social norms, known as the ‘leading eight,’ can establish a cooperative regime. Secondly, we reveal the robustness of these norms against reputation costs and perfect defectors. Our analysis identifies four norms that exhibit resilience in the presence of defectors due to their neutral stance on justified defection and another four that demonstrate robustness against reputation costs through their negative evaluation of unjustified cooperation. The study underscores the need to further research how reputational information is shared within societies to promote cooperation in diverse and complex environments.

Shimizu, Y.,(清水佑輔) Komoto, S., Manome, Y.,(馬目蓉子) & Karasawa, K.(唐沢かおり) (in press).
Reducing benevolent sexism: Focusing on its harm against women and pervasiveness.
慈愛的偏見の軽減：女性に対する影響と普及度に着目して
International Journal of Psychology.
https://doi.org/10.1002/ijop.13251 (Early View)

Although gender equality is a global goal, significant disparity remains between men and women. Benevolent sexism (BS) is widespread and contributes to the maintenance of the gender gap. To reduce BS, many previous studies have implemented long-term intervention programmes. In contrast, we posit that it is necessary to reduce BS efficiently through simpler methods. This study aimed to reduce participants’ BS endorsement by presenting experimental vignettes regarding (a) the harm of BS against women and (b) the pervasiveness of BS. An online experiment was conducted with male and female Japanese participants (n = 816). The results showed that the main effect of presenting the harm of BS against women was significant only among female participants. However, neither the main effect of presenting the pervasiveness of BS nor the interaction between presenting harm and pervasiveness were found. We suggested strategies to reduce BS, especially when endorsed by men. Our experimental manipulation can be conducted in a short time and on many participants simultaneously. More empirical studies aimed at reducing BS should be conducted in the future.

Yamamoto, H., (山本仁志)& Goto, A.(後藤晶) (2024). 
Behavioural strategies in simultaneous and alternating prisoner's dilemma games with/without voluntary participation. 
任意参加の有無による同時および交互の囚人のジレンマゲームにおける行動戦略
Scientific Reports, 14(1), 21890.
https://doi.org/10.1038/s41598-024-73353-4

The Prisoner’s Dilemma is one of the most classic formats for exploring the principle of direct reciprocity. Although numerous theoretical and experimental studies have been conducted, little attention has been paid to the divergence between theoretical predictions and actual human behaviour. In addition, there are two additional essential challenges of experimental research. First, most experimental approaches have focused on games in which two players decide their actions simultaneously, but little is known about alternating games. Another is that there are few experiments on voluntary participation. Here, we conducted experiments on simultaneous games, alternating games, and games with and without voluntary participation for a total of four game patterns and examined the deviation from theoretical predictions for each. The results showed that, contrary to theoretical predictions, humans chose cooperation even after being exploited. We also observed that, with or without voluntary participation, people tended to take the same action they had taken in the previous round. Our results indicate that to understand the mechanisms of human behaviour, we need to integrate findings from behavioural science, psychology, and game theory.

Homma, S.（本間祥吾）, & Takezawa, M.（竹澤正哲）(2024). 
Risk preference as an outcome of evolutionarily adaptive learning mechanisms: An evolutionary simulation under diverse risky environments.
進化適応的な学習メカニズムの産物としてのリスク選好：多様なリスク環境下での進化シミュレーション
PloS one, 19(8), e0307991.
https://doi.org/10.1371/journal.pone.0307991

The optimization of cognitive and learning mechanisms can reveal complicated behavioral phenomena. In this study, we focused on reinforcement learning, which uses different learning rules for positive and negative reward prediction errors. We attempted to relate the evolved learning bias to the complex features of risk preference such as domain-specific behavior manifests and the relatively stable domain-general factor underlying behaviors. The simulations of the evolution of the two learning rates under diverse risky environments showed that the positive learning rate evolved on average to be higher than the negative one, when agents experienced both tasks where risk aversion was more rewarding and risk seeking was more rewarding. This evolution enabled agents to flexibly choose more reward behaviors depending on the task type. The evolved agents also demonstrated behavioral patterns described by the prospect theory. Our simulations captured two aspects of the evolution of risk preference: the domain-specific aspect, behavior acquired through learning in a specific context; and the implicit domain-general aspect, corresponding to the learning rates shaped through evolution to adaptively behave in a wide range of environments. These results imply that our framework of learning under the innate constraint may be useful in understanding the complicated behavioral phenomena.

Yang, F. (楊帆), Ren, M. (任孟浩), & Oshio, A. (小塩真司) (2024). 
The effect of attachment style on mindfulness: findings from a weekly diary study using latent growth modeling. 
愛着スタイルがマインドフルネスに与える影響：潜在成長モデルを用いた週間日記研究による発見
Current Psychology.
 https://doi.org/10.1007/s12144-024-06310-z

The current study aimed to explore whether attachment style could predict the fluctuation of weekly mindfulness. A weekly diary design was adopted across one baseline week and five follow-up weeks. Data from 622 Chinese college students were subjected to latent growth modeling. Results showed attachment anxiety negatively predicted the intercept of acting with awareness, present moment attention, and nonjudging while positively predicting the slope of acting with awareness. Attachment avoidance negatively predicted the intercept of acting with awareness and present moment attention and positively predicted the slope of acting with awareness. These suggest that attachment style may impact the fluctuation of weekly mindfulness. Furthermore, both attachment avoidance and anxiety impact the rate of change of acting with awareness across five weeks. These support the idea that compared to securely attached people, insecurely attached people’s attention may fluctuate more according to their stress level, shifting between external tasks, other people, or themselves.

Matsuo, A.（松尾朗子）, Miura, A.（三浦麻子）, Kitamura, H.（北村英哉）, & Murayama, A.（村山綾） (2024). 
The ebb and flow of morality: The role of purity in the public perceptions of Fukushima's processed water release. 
道徳の「潮目」：福島原発の処理水放出に対する世間の認識における「純粋さ」の役割
Japanese Psychological Research.

The Japanese government’s decision to discharge treated water into the ocean has drawn citizens’ attention, and the evaluation of this issue remains controversial. The themes underlying social issues are connected to the moral foundation of Haidt’s moral foundations theory. Accordingly, these foundations appeal to individuals’ subjective approval of their moral foundations. The treated water issue is related to the purity foundation; thus, the present study aimed to investigate the role of the purity foundation on the support for the treated water issue by collecting data from 1,291 Japanese participants immediately after the first discharge of treated water. To measure the purity-related concept, the Purity Orientation–Pollution Avoidance Scale (POPA) was employed. The results of our multiple regression analysis showed a negative association for the Mental Purity subscale and a positive association for the Respect for Religion subscale of POPA. The different aspects of Japanese purity highlighted by POPA are discussed. This study contributes to a deeper understanding of the mechanisms involved in people’s attitudes toward social issues.

2023年8月下旬に開始された福島第一原発の処理水海洋放出に対する賛否と，道徳基盤や感染忌避傾向，システム正当化傾向との関連を調査しました。

Neff, K.D., & Miyagawa, Y.(宮川裕基) (2024). 
Self-Compassion Scale for Youth (SCS-Y).
思春期を対象としたセルフ・コンパッション尺度
In Medvedev, O.N., Krägeloh, C.U., Siegert, R.J., Singh, N.N. (eds) Handbook of Assessment in Mindfulness Research. Springer
https://doi.org/10.1007/978-3-030-77644-2_104-1

The Self-Compassion Scale for Youth (SCS-Y) is a measure of self-compassion for adolescents aged 10–15. Its structure is based on the Self-Compassion Scale (SCS) for adults. Exploratory structural equation modeling suggests that the SCS-Y represents a bifactor structure identified by a general self-compassion factor and six specific factors: increased self-kindness, common humanity, and mindfulness, as well as reduced self-judgment, isolation, and over-identification. Across four studies, the SCS-Y exhibited high internal reliability. Cronbach’s alpha coefficients, McDonald’s model-based composite reliability, and omega coefficients for the SCS-Y suggest that the use of a total score or six subscales’ scores is warranted. Construct validity of the SCS-Y was established by associations between the SCS-Y and functionally related constructs such as resilience and depression in the expected direction. Levels of self-compassion did not differ by age in the samples of 10–15-year-olds. While three studies did not find sex differences in the level of self-compassion, one study found that adolescent boys were higher in total self-compassion compared to adolescent girls. Overall, these results provide evidence for the psychometric validity of the SCS-Y.

10歳から15歳を対象としたセルフ・コンパッション尺度に関する情報をまとめた論文です。成人を対象としたセルフ・コンパッション尺度と同様に、本尺度は自分への優しさ、共通の人間性、マインドフルネス、自己批判（の低さ)、孤立（の低さ)、過剰同一化（の低さ）という6要素を測定することができます。