Cargando…

Number processing outside awareness? Systematically testing sensitivities of direct and indirect measures of consciousness

In priming research, it is often argued that humans can discriminate stimuli outside consciousness. For example, the semantic meaning of numbers can be processed even when the numbers are so strongly masked that participants are not aware of them. These claims are typically based on a certain patter...

Descripción completa

Detalles Bibliográficos
Autores principales: Zerweck, Iris A., Kao, Chung-Shan, Meyen, Sascha, Amado, Catarina, von Eltz, Martin, Klimm, Maren, Franz, Volker H.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Springer US 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8302564/
https://www.ncbi.nlm.nih.gov/pubmed/33973133
http://dx.doi.org/10.3758/s13414-021-02312-2
_version_ 1783726904225824768
author Zerweck, Iris A.
Kao, Chung-Shan
Meyen, Sascha
Amado, Catarina
von Eltz, Martin
Klimm, Maren
Franz, Volker H.
author_facet Zerweck, Iris A.
Kao, Chung-Shan
Meyen, Sascha
Amado, Catarina
von Eltz, Martin
Klimm, Maren
Franz, Volker H.
author_sort Zerweck, Iris A.
collection PubMed
description In priming research, it is often argued that humans can discriminate stimuli outside consciousness. For example, the semantic meaning of numbers can be processed even when the numbers are so strongly masked that participants are not aware of them. These claims are typically based on a certain pattern of results: Direct measures indicate no conscious awareness of the masked stimuli, while indirect measures show clear priming effects of the same stimuli on reaction times or neurophysiological measures. From this pattern, preserved (unconscious) processing in the indirect task is concluded. However, this widely used standard reasoning is problematic and leads to spurious claims of unconscious processing. Such problems can be avoided by comparing sensitivities of direct and indirect measures. Many studies are affected by these problems, such that a reassessment of the literature is needed. Here, we investigated whether numbers can be processed unconsciously. In three experiments, we replicated and extended well-established effects of number priming over a wide range of stimulus visibilities. We then compared the standard reasoning to a sensitivity analysis, where direct and indirect effects are compared using the same metric. Results show that the sensitivities of indirect measures did not exceed those of direct measures, thereby indicating no evidence for preserved unconscious processing when awareness of the stimuli is low. Instead, it seems that at low visibility there is residual processing that affects direct and indirect measures to a similar degree. This suggests that similar processing modes cause those effects in direct and indirect measures.
format Online
Article
Text
id pubmed-8302564
institution National Center for Biotechnology Information
language English
publishDate 2021
publisher Springer US
record_format MEDLINE/PubMed
spelling pubmed-83025642021-07-27 Number processing outside awareness? Systematically testing sensitivities of direct and indirect measures of consciousness Zerweck, Iris A. Kao, Chung-Shan Meyen, Sascha Amado, Catarina von Eltz, Martin Klimm, Maren Franz, Volker H. Atten Percept Psychophys Article In priming research, it is often argued that humans can discriminate stimuli outside consciousness. For example, the semantic meaning of numbers can be processed even when the numbers are so strongly masked that participants are not aware of them. These claims are typically based on a certain pattern of results: Direct measures indicate no conscious awareness of the masked stimuli, while indirect measures show clear priming effects of the same stimuli on reaction times or neurophysiological measures. From this pattern, preserved (unconscious) processing in the indirect task is concluded. However, this widely used standard reasoning is problematic and leads to spurious claims of unconscious processing. Such problems can be avoided by comparing sensitivities of direct and indirect measures. Many studies are affected by these problems, such that a reassessment of the literature is needed. Here, we investigated whether numbers can be processed unconsciously. In three experiments, we replicated and extended well-established effects of number priming over a wide range of stimulus visibilities. We then compared the standard reasoning to a sensitivity analysis, where direct and indirect effects are compared using the same metric. Results show that the sensitivities of indirect measures did not exceed those of direct measures, thereby indicating no evidence for preserved unconscious processing when awareness of the stimuli is low. Instead, it seems that at low visibility there is residual processing that affects direct and indirect measures to a similar degree. This suggests that similar processing modes cause those effects in direct and indirect measures. Springer US 2021-05-10 2021 /pmc/articles/PMC8302564/ /pubmed/33973133 http://dx.doi.org/10.3758/s13414-021-02312-2 Text en © The Author(s) 2021 https://creativecommons.org/licenses/by/4.0/Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/ (https://creativecommons.org/licenses/by/4.0/) .
spellingShingle Article
Zerweck, Iris A.
Kao, Chung-Shan
Meyen, Sascha
Amado, Catarina
von Eltz, Martin
Klimm, Maren
Franz, Volker H.
Number processing outside awareness? Systematically testing sensitivities of direct and indirect measures of consciousness
title Number processing outside awareness? Systematically testing sensitivities of direct and indirect measures of consciousness
title_full Number processing outside awareness? Systematically testing sensitivities of direct and indirect measures of consciousness
title_fullStr Number processing outside awareness? Systematically testing sensitivities of direct and indirect measures of consciousness
title_full_unstemmed Number processing outside awareness? Systematically testing sensitivities of direct and indirect measures of consciousness
title_short Number processing outside awareness? Systematically testing sensitivities of direct and indirect measures of consciousness
title_sort number processing outside awareness? systematically testing sensitivities of direct and indirect measures of consciousness
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8302564/
https://www.ncbi.nlm.nih.gov/pubmed/33973133
http://dx.doi.org/10.3758/s13414-021-02312-2
work_keys_str_mv AT zerweckirisa numberprocessingoutsideawarenesssystematicallytestingsensitivitiesofdirectandindirectmeasuresofconsciousness
AT kaochungshan numberprocessingoutsideawarenesssystematicallytestingsensitivitiesofdirectandindirectmeasuresofconsciousness
AT meyensascha numberprocessingoutsideawarenesssystematicallytestingsensitivitiesofdirectandindirectmeasuresofconsciousness
AT amadocatarina numberprocessingoutsideawarenesssystematicallytestingsensitivitiesofdirectandindirectmeasuresofconsciousness
AT voneltzmartin numberprocessingoutsideawarenesssystematicallytestingsensitivitiesofdirectandindirectmeasuresofconsciousness
AT klimmmaren numberprocessingoutsideawarenesssystematicallytestingsensitivitiesofdirectandindirectmeasuresofconsciousness
AT franzvolkerh numberprocessingoutsideawarenesssystematicallytestingsensitivitiesofdirectandindirectmeasuresofconsciousness