Predictability effects on word-meaning priming and incidental memory

Previous research has shown that encountering a word in a sentential context that biases its interpretation towards a subordinate meaning aspect leads to that meaning subsequently being more easily accessible (e.g., Curtis et al., 2022). This finding, referred to as word-meaning priming, illustrates the malleability of word meanings, and research within this paradigm has shed some light on the time course and constraints on this type of lexical-semantic updating (e.g., Gaskell et al., 2019; Gilbert et al., 2021; Rodd et al., 2013, 2016). However, the exact mechanism underpinning this flexibility remains contested. One explanation, called the episodic context account (Gaskell et al., 2019; Curtis et al., 2022; Mak et al., 2022), suggests that word-meaning priming is supported by general episodic memory processes, whereby word meanings are initially bound to the context they are encountered in by the hippocampus. Crucially, if word-meaning priming is supported by episodic memory processes, then the strength of word-meaning priming effects should be affected by factors that have previously been shown to affect learning in (other) episodic memory paradigms (e.g., Greve et al., 2018; Quent et al., 2022). One important finding in this regard (replicated across several different paradigms, e.g., van Kesteren et al., 2013; Greve et al., 2018; Quent et al., 2022) is that the expectedness of a stimulus influences the extent to which participants are able to remember that input (see Quent et al., 2021 for a recent review). The main aim of the present study is to test whether the expectedness of a stimulus has an influence on the strength of the word-meaning priming effect, as would be predicted if word-meaning priming is supported by general episodic memory processes (see the ‘study design’ section for details of the experimental design). In the present experiment, participants will be exposed to sentences containing a target word whose interpretation is biased towards a specific aspect of its meaning by the preceding sentential context (i.e., the word-meaning priming manipulation). As stated above, if word-meaning priming is affected by similar factors as have been shown to affect memory in (other) episodic memory paradigms, then the strength of the word-meaning priming effect should be affected by the relative expectedness of the target word. Therefore, the central question is whether expectedness has an impact on word-meaning priming. A subsidiary aim is to test the prediction derived from the models of episodic memory cited above that memory for incidental aspects of the experiment will be better if these are processed in close temporal proximity to unexpected input (compared to expected or neutral input). Cued recall and 2AFC tests probing memory for incidental aspects of the main experiment will address this hypothesis (see ‘incidental memory test’ in the ‘study design’ section below).