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Cognitive and neural bases of decision-making causing civilian casualties during intergroup conflict

Abstract

Civilian casualties occur during military attacks. Such ‘collateral damage’ is prohibited by international laws but increases with substantial consequences when intergroup conflict escalates. Here, we investigate cognitive and neural bases of decision-making processes resulting in civilian harm, using a task that simulates punishment decision-making during intergroup conflict. We test two groups of Chinese participants in a laboratory setting, and members of two ethnic groups (Jewish and Palestinian) in Israel. The results dissociate two psychological constructs, harm preference and harm avoidance, which respectively characterize punishment decision-making related to outgroup combatants and outgroup noncombatants during intergroup conflict. In particular, individuals show decreased avoidance of harming outgroup noncombatants when conflict escalates. Brain imaging (functional magnetic resonance imaging) reveals that decreased harm avoidance is predicted by inhibition of the left middle frontal activity during selection of punishment decisions. Our findings provide insight into the cognitive and neural bases of decision-making involving civilian harm during intergroup conflict.

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Fig. 1: Illustration of the procedure in experiment 1.
Fig. 2: Results of logistic regression parameter analyses in the group and individual conflict conditions in experiment 1.
Fig. 3: Results of logistic regression parameter analyses of the whole sample in experiment 2.
Fig. 4: Behavioural and fMRI results in experiment 3.
Fig. 5: fMRI results of experiment 3.

Data availability

The data that support the findings of this study are available from the corresponding author upon reasonable request.

Code availability

The codes used to analyse the data that support the findings of this study are available from the corresponding author upon reasonable request.

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Acknowledgements

This research was supported by the National Natural Science Foundation of China (projects 31421003, 31871134 and 31661143039), the Ministry of Science and Technology of China (2019YFA0707103) and the Israel Science Foundation (2510/16). We thank the National Center for Protein Sciences at Peking University for assistance with this study. The authors thank L. Zhu, J. Li, and Y. Ma for insightful discussion about experimental design and data analyses, R. Hampton for proof reading, and S. Wang for modification of Fig. 1. The funder had no role in the conceptualization, design, data collection, analysis, decision to publish or preparation of the manuscript.

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X.H. and S.H. conceived the research programme and designed the experiments. X.H., S.Z., N.F., T. W., T.G., S.S.-T., X.W. and S.H. carried out the experiments. X.H., N.F. and S.H. analysed the data. X.H., S.H. and S.S.-T. wrote the paper. M.J.G. reviewed and edited the paper. S.H. supervised the entire work.

Corresponding authors

Correspondence to Xinhuai Wu or Shihui Han.

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Peer review information Nature Human Behaviour thanks Pablo Brañas-Garza, Grit Hein, and the other, anonymous, reviewer(s) for their contribution to the peer review of this work. Primary Handling Editor: Jamie Horder.

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Han, X., Zhou, S., Fahoum, N. et al. Cognitive and neural bases of decision-making causing civilian casualties during intergroup conflict. Nat Hum Behav (2021). https://doi.org/10.1038/s41562-021-01064-1

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