Poster C89, Wednesday, August 21, 2019, 10:45 am – 12:30 pm, Restaurant Hall
Lingering word expectations in recognition memory
Joost Rommers1, Peter Hagoort1, Kara D. Federmeier2;1Donders Institute, Radboud University, 2Beckman Institute, University of Illinois
Expectations may promote rapid language processing, but it is unclear whether they have downstream consequences for what readers ultimately retain. In particular, when an expectation is disconfirmed, is it suppressed, or does it linger? Furthermore, is such suppression or lingering associated with particular memory processes during retrieval and/or comprehension processes during encoding? The present study manipulated word predictability, examined subsequent memory for words that had likely previously been expected (but were never actually presented), and characterized the associated electrophysiological signals. Forty participants read unexpected but plausible sentence endings while their EEG was recorded. The endings either completed a strongly constraining sentence frame wherein they violated a likely expectation (“Be careful, because the top of the stove is very dirty”, where “hot” was expected), or they completed a weakly constraining sentence frame that did not afford a strong, consistent expectation (“He is surprised, because the second object is very dirty”). Additional filler sentences had predictable endings. After reading all of the sentences and performing a brief distraction task (solving math problems), participants took a surprise recognition memory test. The memory test featured Old words that had previously been seen (“dirty”), New words that had not been seen (“hot” after reading the weakly constraining sentence), and Expected words that had been disconfirmed (“hot” after reading the strongly constraining sentence). The EEG signal during the sentence reading phase suggested that readers formed expectations: relative to the weakly constraining condition, strongly constraining sentence frames elicited an alpha/beta power decrease that started prior to critical word onset, and the expectation violations elicited a continued alpha/beta decrease and a late positivity. Signal detection-theoretic analyses of the memory responses revealed that Old/Expected discriminability was worse than Old/New discriminability, suggesting that expectations lingered despite having been disconfirmed. During the memory test, compared with false recognition, correct rejections of Expected words tended to elicit larger N400 amplitudes and a somewhat larger late positivity. Based on previous studies, this suggests that overcoming false memories was associated with less semantic priming and more effortful recollection of episodic details. Finally, during the reading phase, actually presented words (“dirty”) that were subsequently remembered (vs. forgotten) were associated with smaller N400 amplitudes and a larger late positivity. However, the on-line precursors of lingering and suppression remained unclear, as EEG responses to expectation violations did not differ as a function of whether the originally Expected word (“hot”) was subsequently falsely recognized or correctly rejected. Overall, the results show that expectations have downstream consequences beyond rapid processing.
Themes: Reading, Meaning: Combinatorial Semantics
Method: Electrophysiology (MEG/EEG/ECOG)