In-Group Bounded Cooperation:In-Group Bounded Cooperation:

Carsten K.W. De DreuCarsten K.W. De Dreu

University of AmsterdamUniversity of Amsterdam

Department of Psychology, and Center for Department of Psychology, and Center for Experimental Economics and Political Decision Experimental Economics and Political Decision

Making (CREED)Making (CREED)

andand

Netherlands Institute for Advanced StudyNetherlands Institute for Advanced Study

Background and OverviewBackground and Overview

– Multilevel PerspectiveMultilevel Perspective– 1. Individuals are nested in groups that compare, cooperate, 1. Individuals are nested in groups that compare, cooperate,

compete with other groups; Individuals are interdependent compete with other groups; Individuals are interdependent within and between groupswithin and between groups

– 2. Individuals rely on their in-group for survival/prosperity; 2. Individuals rely on their in-group for survival/prosperity; Group survival/prosperity depends on individual Group survival/prosperity depends on individual contributionscontributions

– 3. Individuals are prepared to (enforce in others) 4Cs 3. Individuals are prepared to (enforce in others) 4Cs • Cooperating:Cooperating: making costly contributions to making costly contributions to

group efficiencygroup efficiency• Conforming: Conforming: aligning with majority views, norms, aligning with majority views, norms,

practicespractices• Creating: Creating: advancing new and useful advancing new and useful

insights/ideas/productsinsights/ideas/products• Competing: Competing: aggressing those that threaten in-aggressing those that threaten in-

group functioninggroup functioning

Background and OverviewBackground and Overview

– Multilevel Perspective (c’tnd)Multilevel Perspective (c’tnd)– 4. These 4Cs should be particularly likely when serving in-4. These 4Cs should be particularly likely when serving in-

group (rather than out-group), andgroup (rather than out-group), and• can be traced to the individual (rather than not)can be traced to the individual (rather than not)

reputation; (in)direct reciprocityreputation; (in)direct reciprocity• prevent in-group harm (prevent in-group harm (vs.vs. promoting in-group gain) promoting in-group gain)

loss aversion; survival trumps prosperity needs; reactive loss aversion; survival trumps prosperity needs; reactive vs. instrumental vs. instrumental aggression aggression

– 5. Because of evolutionary pressures (5. Because of evolutionary pressures (viz. viz. Darwin), humans Darwin), humans may be biologically prepared for In-group Bounded 4Cs; if may be biologically prepared for In-group Bounded 4Cs; if truetrue

• 4Cs should be readily observable in “abstract” settings4Cs should be readily observable in “abstract” settings• 4Cs should be intuitive, and not requiring deliberation4Cs should be intuitive, and not requiring deliberation• 4Cs should have clear correlates in (evolutionary 4Cs should have clear correlates in (evolutionary

ancient, sub-cortical) neurobiological circuitries and ancient, sub-cortical) neurobiological circuitries and systems.systems.

Background and Overview: Key FindingsBackground and Overview: Key Findings

Evidence accumulates that 4Cs areEvidence accumulates that 4Cs are

(i)(i)motivated by a desire to benefit the in-group and its members, motivated by a desire to benefit the in-group and its members, rather than to hurt or derogate competing outgroups;rather than to hurt or derogate competing outgroups;

(ii)(ii)Stronger when mechanism for (in)direct reciprocity are present;Stronger when mechanism for (in)direct reciprocity are present;

(iii)(iii)Stronger when stable preferences are pro-social rather than Stronger when stable preferences are pro-social rather than pro-selfpro-self

(iv)(iv)Intuitive and habitual rather than calculated and pre-meditated Intuitive and habitual rather than calculated and pre-meditated

(v)(v)Enhanced under increased availability of oxytocin, a Enhanced under increased availability of oxytocin, a hypothalamic neuropeptide involved in pair-bond formation, hypothalamic neuropeptide involved in pair-bond formation, parent-offspring interactions, and maternal defense. parent-offspring interactions, and maternal defense.

(i) (i) motivated by in-group love not out-motivated by in-group love not out-group hategroup hate

• Economic Games (Dictator, Trust Game, PDG, PPG); Protagonist classified as in-group vs. out-group, stranger; k = 205 effect sizes; Random Effects Model

Balliet, Wu, De Dreu, Psych Bull 2014

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(ii) (ii) stronger when (in)direct reciprocity stronger when (in)direct reciprocity is enabledis enabled

– Full InfoFull Info: Experiments in which : Experiments in which decision maker knows that partner decision maker knows that partner knows decision maker si from knows decision maker si from same/different group same/different group vsvs

– Partial InfoPartial Info: Experiments in which : Experiments in which decision maker knows that partner decision maker knows that partner does NOT know decision maker’s does NOT know decision maker’s groupgroup

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Balliet, Wu, De Dreu, Psych Bull 2014

(iii) stronger when stable preferences are tronger when stable preferences are pro-social rather than pro-selfpro-social rather than pro-self

– Intergroup Competition Game– Players pre-classified as cooperators (pro-socials) vs. non-

cooperators (pro-selves)– Players have (no) option to punish in-group members following

(lack of) investment

Fig.2 Mean aggregate conflict expenditures (total of both groups) over the 20 rounds. The shaded area illustrates the range in which total investments in fighting exceed thevalue of the prize. From Abbink et al., 2012; Economics Letters

Abbink, Brandts et al., Econ Lett 2012

(iii) stronger when stable preferences are tronger when stable preferences are pro-social rather than pro-selfpro-social rather than pro-self

(De Dreu, Group Process Intergr Relat, 2010)

(iv) intuitive rather than calculated and (iv) intuitive rather than calculated and pre-meditated pre-meditated

(De Dreu, Dussel, & Ten Velden, Fr Human Neuroscience, 2015)

(iv) intuitive rather than calculated and (iv) intuitive rather than calculated and pre-meditated pre-meditated

(De Dreu, Dussel, & Ten Velden, Fr Human Neuroscience, 2015)

(v) enhanced under increased (v) enhanced under increased availability of oxytocinavailability of oxytocin

Dreu, Horm & Behav, 2012; De Dreu & Kret, Biol Psychiatry 2015

(v) enhanced under increased (v) enhanced under increased availability of oxytocinavailability of oxytocin

((Overview of Materials and Methods)Overview of Materials and Methods)

• MedicationMedication– Double-Blind Placebo Controlled Study DesignsDouble-Blind Placebo Controlled Study Designs

• Syntocinon Spray (Oxytocin). Placebo manufactured for Syntocinon Spray (Oxytocin). Placebo manufactured for this study (GCP, Helsinki Protocols). this study (GCP, Helsinki Protocols).

• Intranasal administration; loading time 35-40min; 20 – 30 Intranasal administration; loading time 35-40min; 20 – 30 Ss per treatment conditionSs per treatment condition

• SubjectsSubjects– Healthy males (age M = 21); Healthy males (age M = 21);

• Tested between Noon—4PM; no smoking or intense Tested between Noon—4PM; no smoking or intense physical exercise 2h prior to test sessionphysical exercise 2h prior to test session

• Experimental Procedures and TasksExperimental Procedures and Tasks– Individual testing in soundproof cubicles; computer-guided; Individual testing in soundproof cubicles; computer-guided;

self-pacedself-paced• Instructions, behavioral responses, post-test questions, Instructions, behavioral responses, post-test questions,

debriefingdebriefing• No deception; performance-contingent pay (range 0 – No deception; performance-contingent pay (range 0 –

35€).35€).

(v) enhanced under increased availability (v) enhanced under increased availability of oxytocinof oxytocin

Keep1€ = 1€

In-Group

Stallen, De Dreu et al., Psych Science, 2012

(v) enhanced under increased availability (v) enhanced under increased availability of oxytocinof oxytocin

10€

Keep1€ = 1€

In-Group Love

Out-Group Hate

1€ = +0.5€

1€ = +0.5€

1€ = +0.5€

1€ = +0.5€

1€ = +0.5€

1€ = +0.5€

1€ = -0.5€

1€ = -0.5€

1€ = -0.5€

In-Group

Out-Group

De Dreu et al., Science, 2010

(v) enhanced under increased availability (v) enhanced under increased availability of oxytocinof oxytocin

• In PDG, Defection is motivated by Greed (Temptation) and/or Fear (Sucker)

• Payoffs manipulated to increase/reduce Fear (i.e., vulnerability to exploitation by out-group) and Greed (i.e., temptation to exploit out-group)

De Dreu et al., Science, 2010; PLoS One, 2012

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(v) enhanced under increased (v) enhanced under increased availability of oxytocinavailability of oxytocin

• Summary:Summary:• Oxytocin promotes conformity, esp. to in-Oxytocin promotes conformity, esp. to in-

groupgroup• Oxytocin promotes in-group bounded Oxytocin promotes in-group bounded

cooperation and trustcooperation and trust• Oxytocin promotes defense-motivated Oxytocin promotes defense-motivated

competitioncompetition• No evidence for out-group spite and No evidence for out-group spite and

exploitative aggressionexploitative aggression

Summary of Key FindingsSummary of Key Findings

Evidence accumulates that 4Cs (cooperating, conforming, creating, Evidence accumulates that 4Cs (cooperating, conforming, creating, competing) are:competing) are:

(i)(i)motivated by a desire to benefit the in-group and its members, rather motivated by a desire to benefit the in-group and its members, rather than to hurt or derogate competing outgroups;than to hurt or derogate competing outgroups;

(ii)(ii)Stronger when mechanism for (in)direct reciprocity are present;Stronger when mechanism for (in)direct reciprocity are present;

(iii)(iii)Stronger when stable preferences are pro-social rather than pro-selfStronger when stable preferences are pro-social rather than pro-self

(iv)(iv)Intuitive and habitual rather than calculated and pre-meditated Intuitive and habitual rather than calculated and pre-meditated

(v)(v)Enhanced under increased availability of oxytocin, a hypothalamic Enhanced under increased availability of oxytocin, a hypothalamic neuropeptide involved in pair-bond formation, parent-offspring neuropeptide involved in pair-bond formation, parent-offspring interactions, and maternal defense. interactions, and maternal defense.

ImplicationsImplications

Fitting an evolutionary account (Theory of Bounded Generalized Fitting an evolutionary account (Theory of Bounded Generalized Reciprocity) on the root causes of human propensity for Reciprocity) on the root causes of human propensity for cooperation specifically (and group living in general)cooperation specifically (and group living in general)

New avenues for future research: New avenues for future research: structurally mapping 4Cs (little w/r Creating); structurally mapping 4Cs (little w/r Creating); role of social identity; role of social identity; other neurohormonal mechanisms (e.g., testosterone, other neurohormonal mechanisms (e.g., testosterone,

cortisol)cortisol) calibrating intervention in (reducing) prejudice and calibrating intervention in (reducing) prejudice and

(reducing) intergroup violence(reducing) intergroup violence Reconciling findings with work on intergroup contact, Reconciling findings with work on intergroup contact,

diffusion of innovation, between-group exchange and tradediffusion of innovation, between-group exchange and trade Predicting when the world seizes to existPredicting when the world seizes to exist

Thank You

– And…• Conflict & Creativity Lab: Hillie Aaldering,

Matthijs Baas, Lindy Greer, Michel Handgraaf, Mariska Kret, Shaul Shalvi, Femke ten Velden, Eric van Dijk, Gerben Van Kleef, and Jorg Gross

• Funding Agencies: Roy Netherl Acad Sci; Netherl Sci Found; Dutch Judicial Council; U of Amsterdam

DisclosureDisclosure

• Ethics approval, obtained written informed consentEthics approval, obtained written informed consent• Complied with Helsinki Protocol; Complied with Helsinki Protocol; • Did not involve deception; Ss received payment Did not involve deception; Ss received payment

depending on performance; depending on performance; • No conflict of interest; funding sources include:No conflict of interest; funding sources include: