Discovering the Brain Stages of Lexical Decision: Behavioral Effects Originate from a Single Neural Decision Process Hermine S. Berberyan1*, Hedderik van Rijn2, & Jelmer P. Borst1 1 Bernoulli Institute, University of Groningen, Groningen, the Netherlands 2 Department of Experimental Psychology, University of Groningen, Groningen, the Netherlands * Corresponding author: Hermine S. Berberyan,
[email protected] ORCID: Hermine S. Berberyan 0000-0002-3889-5933 Hedderik van Rijn 0000-0002-0461-9850 Jelmer P. Borst 0000-0002-4493-8223 This is a preprint. A peer reviewed publication is Berberyan, H., van Rijn, H., & Borst, J. P. (2021). Discovering the brain stages of lexical decision: Behavioral effects originate from a single neural decision process. Brain and Cognition, 153, 105786. https://doi.org/10.1016/j.bandc.2021.105786 Abstract Lexical decision (LD) – judging whether a sequence of letters constitutes a word – has been widely investigated. In a typical lexical decision task (LDT), participants are asked to respond whether a sequence of letters is an actual word or a nonword. Although behavioral differences between types of words/nonwords have been robustly detected in LDT, there is an ongoing discussion about the exact cognitive processes that underlie the word identification process in this task. To obtain data-driven evidence on the underlying processes, we recorded electroencephalographic (EEG) data and applied a novel machine-learning method, hidden semi-Markov model multivariate pattern analysis (HsMM- MVPA). In the current study, participants performed an LDT in which we varied the frequency of words (high, low frequency) and “wordlikeness” of non-words (pseudowords, random non-words). The results revealed that models with six processing stages accounted best for the data in all conditions.