The fate of the unexpected: Consequences of misprediction on ERP repetition patterns

Lai, Melinh K.

Permalink

https://hdl.handle.net/2142/106149 Copy

Description

Title

The fate of the unexpected: Consequences of misprediction on ERP repetition patterns

Author(s)

Lai, Melinh K.

Issue Date

2019-09-03

Director of Research (if dissertation) or Advisor (if thesis)

Federmeier, Kara D.

Department of Study

Psychology

Discipline

Psychology

Degree Granting Institution

University of Illinois at Urbana-Champaign

Degree Name

M.S.

Degree Level

Thesis

Keyword(s)

prediction, psycholinguistics, N400, ERP

Abstract

Amid increasing interest in the nature and role of prediction in language comprehension, there remains a gap in our understanding of what happens when predictions are disconfirmed. One possibility is that lingering representations of predictions interfere with those of the unexpected words. Alternatively, it is also possible that violating predictions strengthens the representations of unexpected words – e.g., by drawing attention to them and/or making them more distinctive. Here, the consequences of prediction violations are investigated using the ERP repetition effect. Unexpected but plausible words completed strongly and weakly constraining sentences. Three sentences later the critical word was repeated at the end of a weakly constraining sentence. As a control, the critical word was seen only once in a weakly constraining sentence. In Experiment 1, repeated words elicited a reduced N400 and enhanced LPC, with no effect of initial sentence constraint on the size of the repetition effect in either time window. However, a P2 effect that reached significance only for words initially appearing in a weakly constraining context potentially reflects subtle differences in attention or recognition for words initially appearing in weakly constraining contexts. Experiment 2 used the same items, except for items in the control condition, and added strongly constraining filler sentences with expected endings in order to further promote prediction during reading. Once again, for repeated words there was no effect of initial sentence constraint at either the N400 or the LPC. Additionally, the P2 effect observed in Experiment 1 was not seen in the results for Experiment 2. When considered alongside prior results (Rommers & Federmeier, 2018b, 2018a), these findings suggest that prediction eases processing by instantiating expected words while also potentially reducing encoding or allocation of attention to the input. Thus, the language processor may be well-equipped for the noisiness of language, such that prediction violations may be neither as costly – nor as critical – for language comprehension as has sometimes been assumed.

Graduation Semester

2019-12

Type of Resource

text

Permalink

http://hdl.handle.net/2142/106149

Copyright and License Information

Copyright 2019 Melinh Lai

Owning Collections