Socially alerted cognition evoked by a confederate’s mere presence: analysis of reaction-time distributions and delta plots

  • Michael B. Steinborn
  • Lynn Huestegge
Original Article


We examined aspects of social alerting as induced through the presence of an attentive but non-evaluative confederate on mental efficiency. To this end, individuals were administered with a chained mental-arithmetic task (levels: low vs. high demand) in two contextual conditions (levels: alone vs. presence). In addition, we examined self-report measures of subjective state for purposes of control. As a result, the presence (vs. alone) condition improved (not hampered) processing speed (while error rate remained low overall), and this effect was differentially more pronounced for high (vs. low) demand. Reaction-time distributional analyses revealed that improvements in average performance actually originated from a selective speeding-up in the slower percentiles, indicating that social alerting promotes stability of information-processing throughput. These results challenge prevalent theoretical notions of mere-presence effects as individuals became consistently faster and less vulnerable to commit attention failure. Our findings indicate that social presence promotes not only processing speed but volitional steadiness.



We would like to thank the following student research assistants for help with data collection at our lab: Julia Böhme, Kristina Stanzel, Laura Heubeck, Viktoria Dueck, Wiebke Herter.

Compliance with ethical standards

Informed consent

Informed consent was obtained from the participants regarding their agreement with their participation in this research.

Ethical standards

Our study was in accordance with the ethical standards of the institutional and national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

Conflict of interest

All authors declare that there are no conflict of interests.


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Authors and Affiliations

  1. 1.Psychologie IIIUniversität WürzburgWürzburgGermany

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