The neural bases of cooperation and competition: an fMRI investigation

Abstract

Cooperation and competition are two basic modes of social cognition that necessitate monitoring of both one's own and others' actions, as well as adopting a specific mental set. In this fMRI, study individuals played a specially designed computer game, according to a set of predefined rules, either in cooperation with or in competition against another person. The hemodynamic response during these conditions was contrasted to that of the same subjects playing the game independently. Both cooperation and competition stances resulted in activation of a common frontoparietal network subserving executive functions, as well as the anterior insula, involved in autonomic arousal. Moreover, distinct regions were found to be selectively associated with cooperation and competition, notably the orbitofrontal cortex in the former and the inferior parietal and medial prefrontal cortices in the latter. This pattern reflects the different mental frameworks implicated in being cooperative versus competitive with another person. In accordance with evidence from evolutionary psychology as well as from developmental psychology, we argue that cooperation is a socially rewarding process and is associated with specific left medial orbitofrontal cortex involvement.

Fig. 1

Illustration of one trial of the game. The color of the target displayed above the vertical grid indicates which player is building the pattern during this trial, in this case, the yellow player. Black circles correspond to empty slots. The tokens appear automatically every 2000 ms on top of the grid, on the side of the player whose turn it is to play (in this example, the blue player is next). Players have to move the token horizontally until it reaches the desired column, where the token will drop (as if subjected to gravity). Blocking tokens prevent an opponent from completing a pattern (competition); supporting tokens are required to build patterns (cooperation). Note that both cooperative and competitive moves are shown on the same board for illustrative purposes. In the fMRI experiment, each game is played in turn, depending on the instructions given. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)

Fig. 2

Time course of an fMRI sample session. Each of the four sessions comprised 14 blocks of two trials each. Every trial started with an instruction screen with the picture of the other player. Blank screens lasted 3 s between blocks of trials and 1 s between trials.

Fig. 3

Histograms showing the mean percentage of success and standard deviations of participants at achieving the target pattern in cooperation and competition trials across the four fMRI sessions.

Fig. 4

Bilateral activation of the anterior insula found when participants played the computer game to cooperate or to compete with another individual versus playing independently. Clusters are superimposed on a horizontal (z = −8) and coronal (y = 24) MRI sections.

Fig. 5

Left medial orbitofrontal cortex activation cooperation. Clusters are superimposed on horizontal (z = −12) and coronal (y = 36) MRI sections.

Fig. 6

Medial prefrontal cortex activation found in the competition. Clusters are superimposed on horizontal (z = 40) and sagittal (y = −2) MRI sections.