Disambiguating form and lexical frequency effects in MEG responses using homonyms

Abstract

We present an MEG study of homonym recognition in reading, identifying effects of a semantic measure of homonym ambiguity. This measure sheds light on two competing theories of lexical access: the “early access” theory, which entails that lexical access occurs at early (pre 200 ms) stages of processing; and the “late access” theory, which interprets this early activity as orthographic wordform identifcation rather than genuine lexical access. A correlational analysis method was employed to examine effects of the lexical frequencies of distinct words that share the same orthography (homographs) on brain activity. We find that lexical frequency did not affect processing until after 300 ms, while earlier activation was primarily modulated by orthographic form frequency.

Keywords:

• Lexical access
• MEG
• Visual word recognition
• Homonym

ACKNOWLEDGEMENTS

This material is based upon work supported by the National Science Foundation under Grant No. 25-91551-F6539 to Alec Marantz, as well as by a grant from the NYU Abu Dhabi Institute. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

Dylan Simon was supported by Award Number R01MH087882 from the National Institute Of Mental Health as part of the NSF/NIH CRCNS Program.