Human and machine-induced social stress and cognitive performance.

The article examines the effects of social stress on work performance in a laboratory study using a battery of performance tests. Social stress was induced by a combination of negative feedback and ostracism. Participants received negative performance feedback and were ostracised by two confederates of the experimenter. Using a one-way experimental design with three levels (machine-induced stress, human-induced stress, and no stress), 102 participants performed the following tasks: attention, divergent and convergent creativity. Participants also completed questionnaires measuring positive and negative affect, and state self-esteem. The manipulation check confirmed that social stress was successfully implemented. The results showed that social stress increased negative affect and reduced self-esteem. However, performance remained unaffected by social stress on any of the cognitive tasks, with no difference emerging between human-induced and machine-induced stress. The findings provide support for the 'blank-out'-mechanism, which assumes that humans can maintain performance levels even under difficult working conditions. Social stress in the form of negative performance feedback and social exclusion has a negative impact on the affect and self-esteem of humans. However, performance on subsequent tasks was not impaired. TSST: trier social stress test; SSES: state self-esteem scale; PANAS: positive and negative affect schedule; ANOVA: analysis of variance.