Framing a trust game as a power game greatly affects interbrain synchronicity between trustor and trustee

Abstract

We used dual electroencephalography (EEG) to measure brain activity simultaneously in pairs of trustors and trustees playing a 15-round trust game framed as a "trust game" versus a "power game". Four major findings resulted: first, earnings in each round were higher in the trust than in the power game. Second, in the trust game, reaction time for strategic deliberations was significantly longer for the trustee than the trustor. In the power game, however, the trustee took longer to think about how much money to repay, whereas the trustor took longer to think about how much money to invest. Third, prediction accuracy for the amount exchanged was higher in the trust game than in the power game. Fourth, interbrain synchronicity gauged with the phase-locking value of alpha bands in the brainespecially the frontal and central regionswas higher in the power game than in the trust game. We infer that this last finding reflects elevated mutual strategic deliberation in the power game. These behavioral and neuroscience-based findings give a better understanding of the framing effects of a trust game on the strategic deliberations of both trustor and trustee seeking to attain wealth.

Interactional synchrony: signals, mechanisms and benefits

“…What this second participant receives is automatically tripled, and she/he may decide what if anything to return to the first participant. Playing this game induces greater neuronal synchrony between participants when it is framed as a power instead of a trust game ( Sun et al , 2019 ).…”

Trust Games and Beyond

“…They show that players in the role corresponding to a trustor trusted more if the instructions called the other players “partners” rather than “opponents.” However, in many implementations of the Trust Game, the word “Trust” is not mentioned at all, hereby avoiding framing effects. In an EEG experiment, Sun et al (2019) framed a (repeated) Trust Game either literally as a “Trust Game,” or alternatively as a “Power Game,” and found that earnings (and hence trusting behavior) were larger in the first case.…”

Evolutionary-shaped goal orientation in Homo sapiens: how life sciences contribute to a better understanding of salespeople as knowledge brokers

“…This popular belief has its source in the social psychology literature on the synchronization of primitive behaviors, such as mimicking body movements or word imitation (e.g., Bargh 2011). Sun et al (2019) used EEG to study interbrain synchronization in the interactions between two actors playing an iterative trust game (Berg, Dickhaut, and McCabe 1995) to discover whether social learning about each other would influence their mutual level of trust. Observing two people interacting on a social task involves measuring the direct activity in both brains simultaneously (Babiloni and Astolfi 2014, 77).…”

“…In the study by Sun et al (2019), the researchers hypothesized that social learning is affected by two complementary strategic decisions made by both players. The first involves trust as such, defined here as a "willingness to show vulnerability by taking a risk."…”

“…Most studies, however, focus on simple tasks, such as finger tapping, but as we have seen, knowledge brokering is about social learning. During the performance of a social-learning task, Sun et al (2019) showed that it has become easy to compute, for example, the phaselocking value to gauge the interbrain synchronicity (see Study 5).…”