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Additional Information

Competing Interests

The authors declare that they have no competing interests.

Author Contributions

Sebastiaan Mathôt conceived and designed the experiments, performed the experiments, analyzed the data, wrote the paper, prepared figures and/or tables, reviewed drafts of the paper.

Jasper Fabius wrote the paper, reviewed drafts of the paper.

Elle van Heusden performed the experiments, wrote the paper, reviewed drafts of the paper.

Stefan Van der Stigchel wrote the paper, reviewed drafts of the paper.

Human Ethics

The following information was supplied relating to ethical approvals (i.e., approving body and any reference numbers):

We have re-used data that was previously collected for a different purpose as part of another study. This other study was approved by the ethics committee of Utrecht University, and all participants had signed informed consent before participating. See

Data Deposition

The following information was supplied regarding data availability:


The research leading to these results has received funding from: the People Programme (Marie Curie Actions) of the European Union’s Seventh Framework Programme (FP7/2007-2013) under REA grant agreement n° 622738 awarded to Sebastiaan Mathôt. This work is part of the research programme VENI with project number 451-16-023, which is financed by the Netherlands Organisation for Scientific Research (NWO). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

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