Replicating the unconscious working memory effect: a multisite Registered Report

Abstract

Although in recent years some studies have found evidence suggesting that working memory (WM) may operate on unconscious perceptual contents, decisive demonstrations of the existence of unconscious WM are lacking. In the present Registered Report, we replicate the first study on this topic by Soto et al. (Working memory without consciousness. Curr Biol 2011;21:R912–3.): a visual discrimination task asking participants to report the direction in which a subliminal Gabor grating was rotated after a 2-s delay. We acquired a multisite sample from 19 laboratories, with a larger number of participants (N = 531) and trials (720 in two sessions) than those typically used in previous studies. As a result, a large-sample, international, and open-access dataset is now available for researchers and future analyses. Furthermore, some minimal baseline requirements were guaranteed for the experimental task (i.e. number of valid trials, motivation, and consistent labels for the Perceptual Awareness Scale). The results showed (1) above-chance WM performance in cue-present trials reported as unseen (.55 accuracy), (2) a significant positive correlation between WM performance and cue detection sensitivity (r = .228), and (3) a significant above-chance intercept in the regression of performance on sensitivity (β0 = .521). These findings suggest that WM can operate on unconscious representations, although it remains positively associated with perceptual sensitivity. Crucially, because measurement error could compromise the interpretation of these three results, we provide evidence for our measures’ excellent reliability and, more fundamentally, for their validity.This Registered Report was funded by the ‘Funding Consciousness Research with Registered Reports’ initiative from the Center for Open Science. A.F.M. was supported by grant PRE2021-097654 from the Spanish Ministry of Science and Innovation. R.R.S. and M.A.V. were supported by grant CNS2022-135346 from Agencia Estatal de Investigación/FEDER UE. D.R.S. was supported by grant ES/S014616/1 from the UK Economic and Social Research Council. D.S. acknowledges support from the Basque Government through the BERC 2022–2025 programme, from Agencia Estatal de Investigación, through the ‘Severo Ochoa’ Programme for Centres/Units of Excellence in R&D (CEX2020-001010-S), and also from project grant PID2019-105494GB-I00. M.A.V. and A.F.M. were supported by grant PID2020-118583GB-I00 from Agencia Estatal de Investigación/FEDER UE. External collaborators were also supported by the following funders: P.A. was supported by an F.R.S.-FNRS Research Project T003821F (40003221) to A.C. F.B. was supported by Fundação para a Ciência e Tecnologia (CEECIND/03661/2017). A.C. is a Research Director with the F.R.S.-FNRS (Belgium) and a fellow of the Canadian Institute for Advanced Research (Brain, Mind and Consciousness programme), funded by European Research Council Advanced Grant #101055060 ‘EXPERIENCE’. F.G.F. was supported by a predoctoral fellowship from the Spanish Ministry of Science, Innovation and Universities (FPU20/00826). J.A.H., A.P., P.R.M., and M.J. were supported by grant PID2021-125842NB-I00 from Agencia Estatal de Investigación. S.M.H. was supported by the Japan Society for the Promotion of Science (JSPS) KAKENHI ‘Early-Career Scientists’ (24K16877). A.I. was supported by the HSS Seed Fund from the National University of Singapore (#A-8001370-00-00). A.I. would like to thank Shiyang Wu and Mingyuan Yang for help with data collection. P.S. was supported by FPU grant FPU20/01946 from the Spanish Ministry of Science and Innovation