Let them eat ceke: An electrophysiological study of form-based prediction in rich naturalistic contexts

It is well-established that people make predictions during language comprehension--the nature and specificity of these predictions, however, remain unclear. For example, do comprehenders routinely make predictions about which words (and phonological forms) might come next in a conversation, or do they simply make broad predictions about the gist of the unfolding context? Prior EEG studies using tightly controlled experimental designs have shown that form-based prediction can occur during comprehension, as N400s to unexpected words are reduced when they resemble the form of a predicted word (e.g., ceke when expecting cake). One limitation, however, is that these studies often create environments that are optimal for eliciting form-based prediction (e.g., highly constraining sentences, slower-than-natural rates of presentation). Thus, questions remain about whether form-based prediction can occur in settings that more closely resemble everyday comprehension. To address this, the present study explores form-based prediction during naturalistic spoken language comprehension. English-speaking adults listened to a story in which some of the words had been altered. Specifically, we experimentally manipulated whether participants heard the original word from the story (cake), a form-similar nonword (ceke), or a less-similar nonword (vake). Half of the target words were predictable given their context, and the other half were unpredictable. Consistent with the prior work, we found reduced N400s for form-similar nonwords (ceke) relative to less-similar nonwords (vake)-but only in predictable contexts. This study demonstrates that form-based prediction can emerge in naturalistic contexts, and therefore, it is likely to be a common aspect of language comprehension in the wild. (PsycInfo Database Record (c) 2025 APA, all rights reserved).