The psychology of intergroup conflict: A review of theories and measures

Abstract We review psychological research on intergroup conflict. First, we outline psychological perspectives on forms and functions of groups. Second, we present the most influential psychological theories of intergroup conflict and describe their similarities and differences in predicting individual prejudice, discrimination, and conflict engagement. Third, we review popular measures of intergroup discrimination, including rating measures, behavioral measures, and allocation tasks. Furthermore, we call for a refined semantic framework to structure and differentiate between different measures of intergroup bias. Fourth, we highlight several interventions that can de-bias intergroup relations and facilitate conflict resolution. Lastly, we propose that research on the psychology of intergroup conflict may benefit from a stronger interdisciplinary orientation regarding both theoretical perspectives and methods used and point out promising avenues for future research.

[1]  B. Altemeyer,et al.  The Other “Authoritarian Personality” , 1998 .

[2]  Hannes Rusch,et al.  The evolutionary interplay of intergroup conflict and altruism in humans: a review of parochial altruism theory and prospects for its extension , 2014, Proceedings of the Royal Society B: Biological Sciences.

[3]  Stephen C. Wright,et al.  Vicarious intergroup contact effects , 2011 .

[4]  M. Deutsch,et al.  A study of normative and informational social influences upon individual judgement. , 1955, Journal of abnormal psychology.

[5]  J. Duckitt,et al.  Right-Wing Authoritarianism and Political Intolerance among Whites in the Future Majority-Rule South Africa , 1994 .

[6]  M. Hornsey.  Social Identity Theory and Self‐categorization Theory: A Historical Review , 2008 .

[7]  M. Hewstone,et al.  Crossed Categorization in Common Ingroup Contexts , 2006, Personality & social psychology bulletin.

[8]  R. Wrangham,et al.  The evolutionary anthropology of war , 2017 .

[9]  S. Asch.  Effects of Group Pressure Upon the Modification and Distortion of Judgments , 1951 .

[10]  W. Güth,et al.  Determinants of in-group bias: Is group affiliation mediated by guilt-aversion? , 2009 .

[11]  H. Tajfel.  Human Groups and Social Categories: Studies in Social Psychology , 1981 .

[12]  J. Baron.  Confusion of Group Interest and Self-Interest in Parochial Cooperation on Behalf of a Group , 2001 .

[13]  S. Gaertner,et al.  Intergroup Threat and Outgroup Attitudes: A Meta-Analytic Review , 2006 .

[14]  S. Bowles.  Did Warfare Among Ancestral Hunter-Gatherers Affect the Evolution of Human Social Behaviors? , 2009, Science.

[15]  M. Hogg,et al.  Rediscovering the social group: A self-categorization theory. , 1989 .

[16]  Michael Jay Weiner,et al.  The “Lost Letter Technique” as a Predictor of the 1972 Presidential Election , 1973 .

[17]  P. Devine,et al.  Classic and Contemporary Analyses of Racial Prejudice , 2008 .

[18]  William A. Cunningham,et al.  Performance on Indirect Measures of Race Evaluation Predicts Amygdala Activation , 2000, Journal of Cognitive Neuroscience.

[19]  Jens H. Hellmann,et al.  “A letter for Dr. Outgroup”: on the effects of an indicator of competence and chances for altruism toward a member of a stigmatized out-group , 2015, Front. Psychol..

[20]  T. Yamagishi,et al.  The Group as the Container of Generalized Reciprocity , 2000 .

[21]  G. Semin,et al.  Language use in intergroup contexts: the linguistic intergroup bias. , 1989, Journal of personality and social psychology.

[22]  M. Hewstone,et al.  Multiple categorization and implicit intergroup bias: differential category dominance and the positive–negative asymmetry effect , 2001 .

[23]  Michael Wenzel,et al.  Superordinate identities and intergroup conflict: The ingroup projection model , 2007 .

[24]  H. Tajfel,et al.  The Social Identity Theory of Intergroup Behavior. , 2004 .

[25]  K. Fiedler,et al.  The cognitive functions of linguistic categories in describing persons: Social cognition and language. , 1988 .

[26]  M. Diehl.  The Minimal Group Paradigm: Theoretical Explanations and Empirical Findings , 1990 .

[27]  Nir Halevy,et al.  “In-Group Love” and “Out-Group Hate” as Motives for Individual Participation in Intergroup Conflict , 2008, Psychological science.

[28]  Mina Cikara,et al.  Science Perspectives on Psychological the Neuroscience of Intergroup Relations: an Integrative Review on Behalf Of: Association for Psychological Science the Neuroscience of Intergroup Relations: an Integrative Review , 2022 .

[29]  Isabel Thielmann,et al.  Who Does (Not) Participate in Intergroup Conflict? , 2016 .

[30]  Ori Weisel,et al.  “In-Group Love” and “Out-Group Hate” in Repeated Interaction Between Groups , 2012 .

[31]  Phillip Atiba Goff,et al.  The space between us: stereotype threat and distance in interracial contexts. , 2008, Journal of personality and social psychology.

[32]  A. Gardner,et al.  Sixteen common misconceptions about the evolution of cooperation in humans , 2011 .

[33]  Gary Bornstein,et al.  The free-rider problem in intergroup conflicts over step-level and continuous public goods. , 1992 .

[34]  J. A. Cameron,et al.  Children's Lay Theories About Ingroups and Outgroups: Reconceptualizing Research on Prejudice , 2001 .

[35]  N. Halevy.  Preemptive Strikes: Fear, Hope, and Defensive Aggression , 2017, Journal of personality and social psychology.

[36]  David R. Karp,et al.  Raising the minimum in the minimal group paradigm. , 1993 .

[37]  Bertram Gawronski,et al.  Handbook of implicit social cognition : measurement, theory,and applications , 2010 .

[38]  Yan Chen,et al.  Group Identity and Social Preferences , 2009 .

[39]  B. Lickel,et al.  Elements of a Lay Theory of Groups: Types of Groups, Relational Styles, and the Perception of Group Entitativity , 2001 .

[40]  C. Sibley,et al.  Dangerous and competitive worldviews: A meta-analysis of their associations with Social Dominance Orientation and Right-Wing Authoritarianism , 2013 .

[41]  T. Pettigrew.  Intergroup contact theory. , 1998, Annual review of psychology.

[42]  M. Sherif.  Superordinate Goals in the Reduction of Intergroup Conflict , 1958, American Journal of Sociology.

[43]  H. Tajfel,et al.  An integrative theory of intergroup conflict. , 1979 .

[44]  A. Isen,et al.  Group Representations and Intergroup Bias: Positive Affect, Similarity, and Group Size , 1995 .

[45]  S. Otten,et al.  Positive-Negative Asymmetry in Social Discrimination: Valence of Evaluation and Salience of Categorization , 2000 .

[46]  Gary Bornstein,et al.  Intergroup Conflict: Individual, Group, and Collective Interests , 2003, Personality and social psychology review : an official journal of the Society for Personality and Social Psychology, Inc.

[47]  Michael R. Healy,et al.  Ingroup Bias and Self-Esteem: A Meta-Analysis , 2000 .

[48]  Axel Ockenfels,et al.  Beliefs and ingroup favoritism , 2014 .

[49]  G. Āllport.  The Nature of Prejudice , 1954 .

[50]  Debraj Ray,et al.  Ethnicity and Conflict: Theory and Facts , 2012, Science.

[51]  Etienne P LeBel,et al.  What Do Implicit Measures Tell Us?: Scrutinizing the Validity of Three Common Assumptions , 2007, Perspectives on psychological science : a journal of the Association for Psychological Science.

[52]  C. D. De Dreu.  Social value orientation moderates ingroup love but not outgroup hate in competitive intergroup conflict , 2010 .

[53]  Marilynn B. Brewer,et al.  Optimal distinctiveness, social identity, and the self. , 2003 .

[54]  C. Fershtman,et al.  Trust and discrimination in a segmented society: An experimental approach , 2001 .

[55]  Chester A. Insko,et al.  Explanations of interindividual – intergroup discontinuity: A review of the evidence , 2007 .

[56]  Adeya Richmond,et al.  Academic and Psychological Functioning in Late Adolescence: The Importance of School Belonging , 2007 .

[57]  Laura Fortunato,et al.  A solution to the collective action problem in between-group conflict with within-group inequality , 2014, Nature Communications.

[58]  M. Hogg.  Subjective Uncertainty Reduction through Self-categorization: A Motivational Theory of Social Identity Processes , 2000 .

[59]  C. N. Macrae,et al.  Out of mind but back in sight: Stereotypes on the rebound , 1994 .

[60]  Muzafer Sherif,et al.  In common predicament : social psychology of intergroup conflict and cooperation , 1967 .

[61]  Mark Rubin,et al.  Intergroup bias. , 2002, Annual review of psychology.

[62]  R. Janoff-Bulman,et al.  Lessons from Morality-Based Social Identity: The Power of Outgroup “Hate,” Not Just Ingroup “Love” , 2013 .

[63]  G. Bornstein,et al.  Relative deprivation and intergroup competition , 2010 .

[64]  Gary Bornstein,et al.  Cooperation in Intergroup and Single-Group Social Dilemmas , 1994 .

[65]  H. Kelley,et al.  The social psychology of groups , 1960 .

[66]  Ori Weisel,et al.  “Ingroup love” and “outgroup hate” in intergroup conflict between natural groups , 2015, Journal of experimental social psychology.

[67]  Thomas F. Pettigrew,et al.  How does intergroup contact reduce prejudice? Meta‐analytic tests of three mediators , 2008 .

[68]  Daniel Balliet,et al.  Ingroup favoritism in cooperation: a meta-analysis. , 2014, Psychological bulletin.

[69]  M. Brewer.  In-group bias in the minimal intergroup situation: A cognitive-motivational analysis. , 1979 .

[70]  Samuel Bowles,et al.  Being human: Conflict: Altruism's midwife , 2008, Nature.

[71]  T. Yamagishi,et al.  Parochial altruism: does it explain modern human group psychology? , 2016 .

[72]  Anja Eller,et al.  Improving intergroup relations through direct, extended and other forms of indirect contact , 2011 .

[73]  Jeroen C.J.M. van den Bergh,et al.  Evolution of parochial altruism by multilevel selection , 2011 .

[74]  R. Bond,et al.  Group Size and Conformity , 2005 .

[75]  Klaus M. Schmidt,et al.  The Economics of Fairness, Reciprocity and Altruism--Experimental Evidence and New Theories. , 2005 .

[76]  S Milgram,et al.  Some Conditions of Obedience and Disobedience to Authority , 1965 .

[77]  C. Navarrete,et al.  Evolution and the psychology of intergroup conflict: the male warrior hypothesis , 2012, Philosophical Transactions of the Royal Society B: Biological Sciences.

[78]  T. Yamagishi,et al.  Social exchange and solidarity: in-group love or out-group hate? , 2009 .

[79]  R. Baumeister,et al.  The need to belong: desire for interpersonal attachments as a fundamental human motivation. , 1995, Psychological bulletin.

[80]  O. J. Harvey,et al.  Intergroup Conflict And Cooperation: The Robbers Cave Experiment , 2013 .

[81]  Rhiannon N. Turner,et al.  Imagined Intergroup Contact: Theory, Paradigm and Practice , 2009 .

[82]  Linda R. Tropp,et al.  A meta-analytic test of intergroup contact theory. , 2006, Journal of personality and social psychology.

[83]  Roman M. Sheremeta,et al.  War and Conflict in Economics: Theories, Applications, and Recent Trends , 2017 .

[84]  M. Hewstone,et al.  Differential Evaluation of Crossed Category Groups: Patterns, Processes, and Reducing Intergroup Bias , 1999 .

[85]  A. Greenwald,et al.  Measuring individual differences in implicit cognition: the implicit association test. , 1998, Journal of personality and social psychology.

[86]  Avner Ben-Ner,et al.  Identity and in-group/out-group differentiation in work and giving behaviors: Experimental evidence , 2009 .

[87]  W. Stephan,et al.  An Integrated Threat Theory of Prejudice , 2000 .

[88]  B. Lickel,et al.  Varieties of groups and the perception of group entitativity. , 2000, Journal of personality and social psychology.

[89]  J. Baron.  The Illusion of Morality as Self-Interest: A Reason to Cooperate in Social Dilemmas , 1997 .

[90]  M. Sherif,et al.  Groups in harmony and tension : an integration of studies on intergroup relations , 1954 .

[91]  Enrique Fatas,et al.  Globalization and human cooperation , 2009, Proceedings of the National Academy of Sciences.

[92]  Arnold K. Ho,et al.  The nature of social dominance orientation: Theorizing and measuring preferences for intergroup inequality using the new SDO₇ scale. , 2015, Journal of personality and social psychology.

[93]  M. Platow,et al.  Examining the Preconditions for Psychological Group Membership , 2012 .

[94]  K. Abbink,et al.  Parochial Altruism in Inter-Group Conflicts , 2012 .

[95]  Samuel Bowles,et al.  Supporting Online Material Materials and Methods Som Text Figs. S1 and S2 Table S1 References and Notes the Coevolution of Parochial Altruism and War , 2022 .

[96]  T. Burns,et al.  Relative Deprivation and Social Justice. A Study of Attitudes to Social Inequality in Twentieth-Century England , 1966 .

[97]  E. Wilson,et al.  The Social Conquest of Earth , 2013 .

[98]  John Tooby,et al.  Groups in mind : the coalitional roots of war and morality , 2010 .

[99]  G. Moran,et al.  A meta-analysis of the association between authoritarianism and jurors' perceptions of defendant culpability. , 1993 .

[100]  B. Ann Bettencourt,et al.  Cooperation and the reduction of intergroup bias: The role of reward structure and social orientation ☆ , 1992 .

[101]  Shaul Shalvi,et al.  Oxytocin promotes human ethnocentrism , 2011, Proceedings of the National Academy of Sciences.

[102]  K. Charlton,et al.  Status differences and in-group bias: a meta-analytic examination of the effects of status stability, status legitimacy, and group permeability. , 2001, Psychological bulletin.

[103]  Robert Böhm.  Intuitive Participation in Aggressive Intergroup Conflict: Evidence of Weak Versus Strong Parochial Altruism , 2016, Front. Psychol..

[104]  John Thibaut,et al.  On the measurement of social orientations in the minimal group paradigm , 1983 .

[105]  Audrey J. Murrell,et al.  How does cooperation reduce intergroup bias , 1990 .

[106]  C. Dreu,et al.  Parochial cooperation in humans: forms and functions of self-sacrifice in intergroup conflict , 2014 .

[107]  T. Gurr,et al.  Why Men Rebel. , 1970 .

[108]  N. Miller,et al.  The Roles of Ingroup Identification and Outgroup Entitativity in Intergroup Retribution , 2008, Personality & social psychology bulletin.

[109]  Oliver Kirchkamp,et al.  Social categorization and group-motivated interindividual–intergroup discontinuity , 2013 .

[110]  Donald T. Campbell,et al.  Ethnocentric and other altruistic motives , 1966 .

[111]  Hannes Rusch,et al.  What Makes People Go to War? Defensive Intentions Motivate Retaliatory and Preemptive Intergroup Aggression , 2015 .

[112]  Thomas E. Joiner,et al.  Perceived Burdensomeness And Suicidality: Two Studies On The Suicide Notes Of Those Attempting And Those Completing Suicide , 2002 .

[113]  H. Tajfel,et al.  Social categorization and intergroup behaviour , 1971 .

[114]  S. Fiske.  What We Know Now About Bias and Intergroup Conflict, the Problem of the Century , 2002 .

[115]  D. Campbell.  Common fate, similarity, and other indices of the status of aggregates of persons as social entities , 2007 .

[116]  S. Gavrilets,et al.  The logic of animal intergroup conflict: A review , 2017 .

[117]  F. Pratto,et al.  Social Dominance: An Intergroup Theory of Social Hierarchy and Oppression , 1999 .

[118]  F. H. Hankins,et al.  The Psychology of Social Norms , 1937 .

[119]  Linnda R. Caporael,et al.  An Evolutionary Perspective on Social Identity: Revisiting Groups. , 2006 .

[120]  Chris G. Sibley,et al.  Prejudice : A Meta-Analysis and Theoretical Review , 2008 .

[121]  Joshua D. Greene,et al.  The Duty to Support Nationalistic Policies: The Duty to Support Nationalistic Policies , 2013 .

[122]  A. Gat.  Proving communal warfare among hunter‐gatherers: The quasi‐rousseauan error , 2015, Evolutionary anthropology.

[123]  Walter G. Stephan,et al.  The Role of Threat in Intergroup Relations , 2009 .

[124]  J. Baron.  Parochialism as a Result of Cognitive Biases , 2009 .

[125]  Jack L. Vevea,et al.  Beyond the group mind: a quantitative review of the interindividual-intergroup discontinuity effect. , 2003, Psychological bulletin.

[126]  T. Adorno.  The Authoritarian Personality , 1950 .

[127]  Hannes Rusch.  Asymmetries in altruistic behavior during violent intergroup conflict. , 2013, Evolutionary psychology : an international journal of evolutionary approaches to psychology and behavior.

[128]  Steve Hinkle,et al.  The Social Identity Perspective , 2004 .

[129]  Robert Rybnicek,et al.  Social Preferences in Inter-Group Conflict , 2017 .

[130]  Rupert Brown,et al.  Group Processes: Dynamics Within and Between Groups , 1988 .

[131]  N. Christakis,et al.  Formation of raiding parties for intergroup violence is mediated by social network structure , 2016, Proceedings of the National Academy of Sciences.

[132]  Zsombor Z. Méder,et al.  In-group defense, out-group aggression, and coordination failures in intergroup conflict , 2016, Proceedings of the National Academy of Sciences.

[133]  A. Griffin,et al.  Social semantics : altruism , cooperation , mutualism , strong reciprocity and group selection , 2007 .