Supplemental Materials

Press CRTT to Measure Aggressive Behavior: The Unstandardized Use of the Competitive Reaction Time Task in Aggression Research

by M. Elson et al., 2013, Psychological Assessment

http://dx.doi.org/10.1037/a0035569

Results of Study 1

In the overall sample, only one predicted effect of in-game violence or helping on post-game aggressiveness and helpfulness was significant: Post-game helpfulness was significantly higher in the “help” condition compared to the “rescue” condition, t(210) = 3.25, p = .001, g = 0.62. There was an interaction effect of condition and participant sex, however. In the male subsample, the same effect was found, t(182) = 2.99, p = .002, g = 0.63. Additionally, post-game CRTT scores were significantly increased in the “kill” condition compared to the non-violent “help” condition, t(182) = 2.14, p = .017, g = 0.46, and to the non-violent “treasure hunt” condition, t(182) = 1.96, p = .026, g = 0.40. Also, post-game CRTT scores were significantly higher in the “rescue” condition compared to the “help” condition, t(182) = 1.76, p = .040, g = 0.38. In the female subsample, however, there were no significant differences found for post-game CRTT scores, but post-game helpfulness was significantly higher in the “help” condition compared to the “kill” condition t(24) = 2.28, p = .016, g = 0.99.

For further information on Study 1, please see Mohseni (2013).

Results of Study 2

SCL was not significantly influenced by displayed violence, F(1, 80) = 1.75, p = .189, ω = .09, or game speed, F(1, 80) = 0.25, p = .616, ω = .0. There was also no effect of violence, F(1, 80) = 0.00, p = .965, ω = .0, or game speed, F(1, 80) = 0.37, p = .546, ω = .0, on HR. Measure one for aggression, mean volume, was not affected by displayed violence, F(1, 80) = 3.28, p = .074, ω = .16, or game speed, F(1, 80) = 0.98, p = .324, ω = .0. Similarly, there were also no significant effects on mean duration by displayed violence, F(1, 80) = 0.95, p = .334, ω = .0, or game speed, F(1, 80) = 0.07, p = .784, ω = .0. There were no differences between males and females for both measures of aggression. However, there were significant main effects for the two behavioral measures. The greater the violence, F(1, 80) = 14.24, p < .001, ω = .35, or the game speed, F(1, 80) = 4.06, p = .047, ω = .17, the more pressure was exerted on mouse and keyboard during play. A higher pace of action led to a decrease in body movement and to an increase in pressure on the input devices, F(1, 80) = 10.47, p = .002, ω = .31. This was most likely due to higher demands on the participants’ motor capacities.

For further information on Study 2, please see Elson et al. (in press).

Results of Study 3

Participants in the losing condition chose higher duration settings in the first trial of the CRTT (M = 3.31, SD = 2.08) than those who won (M = 2.41, SD = 1.79), F(1, 72) = 4.24, p = .043, ω = .20. There was no effect of gender of the aggression measure. While participants in the trash-talking condition selected higher duration settings (M = 3.05, SD = 2.02) than those in the no-trash-talk condition (M = 2.67, SD = 1.94), this effect was non-significant, F(1, 72) = 0.85, p = .36, ω = .0. There was no interaction effect between the two treatments. A potential mediation through negative emotions was tested in a structural equation model. The overall fit of the model was excellent: χ² (df = 24) = 21.3, p = .62.[1] Losing had a significant effect on the latent variable negative emotions (β = .53, p < .001). Trash-talking, however, only had a very small and non-significant effect (β = .13, p = .20). The effect of negative emotions on aggression was small, but significant (β = .28, p .05) and the indirect effect of losing on post-game aggression was also significant (bootstrapped bias-corrected 95%-CI for the standardized indirect effect: [.01, .33]).

For further information on Study 3, please see Breuer et al. (in press).

References

Breuer, J., Scharkow, M., & Quandt, T. (in press). Sore losers? A reexamination of the frustration-aggression hypothesis for colocated video game play. Psychology of Popular Media Culture.

Elson, M., Breuer, J., Van Looy, J., Kneer, J., & Quandt, T. (in press). Comparing apples and oranges? Evidence for pace of action as a confound in research on digital games and aggression. Psychology of Popular Media Culture. doi:10.1037/ppm0000010

Mohseni, M. R. (2013). Virtuelle Nothilfe. Ein Experiment zum Effekt von virtueller Hilfe, Gewalt und Nothilfe auf Hilfe- und Gewaltverhalten [An experiment on the effect of virtual helping, violence, and emergency assistance on helping and violent behavior] (Doctoral dissertation). University of Osnabrück, Germany.

[1] Root Mean Square Error of Approximation (RMSEA) = .00; Standardized Root Mean Square Residual (SRMR) = .06; Comparative Fit Index (CFI) approaching 1.