You are here

Orthographic familiarity, phonological legality and number of orthographic neighbours affect the onset of ERP lexical effects

Orthographic familiarity, phonological legality and number of orthographic neighbours affect the onset of ERP lexical effects

Authors: 
Proverbio A.M. & Adorni R.
Year: 
2008
Journal: 
Behavioral and Brain Functions
Abstract: 

Background: It has been suggested that the variability among studies in the onset of lexical effects
may be due to a series of methodological differences. In this study we investigated the role of
orthographic familiarity, phonological legality and number of orthographic neighbours of words in
determining the onset of word/non-word discriminative responses.
Methods: ERPs were recorded from 128 sites in 16 Italian University students engaged in a lexical
decision task. Stimuli were 100 words, 100 quasi-words (obtained by the replacement of a single
letter), 100 pseudo-words (non-derived) and 100 illegal letter strings. All stimuli were balanced for
length; words and quasi-words were also balanced for frequency of use, domain of semantic
category and imageability. SwLORETA source reconstruction was performed on ERP difference
waves of interest.
Results: Overall, the data provided evidence that the latency of lexical effects (word/non-word
discrimination) varied as a function of the number of a word's orthographic neighbours, being
shorter to non-derived than to derived pseudo-words. This suggests some caveats about the use
in lexical decision paradigms of quasi-words obtained by transposing or replacing only 1 or 2 letters.
Our findings also showed that the left-occipito/temporal area, reflecting the activity of the left
fusiform gyrus (BA37) of the temporal lobe, was affected by the visual familiarity of words, thus
explaining its lexical sensitivity (word vs. non-word discrimination). The temporo-parietal area was
markedly sensitive to phonological legality exhibiting a clear-cut discriminative response between
illegal and legal strings as early as 250 ms of latency.
Conclusion: The onset of lexical effects in a lexical decision paradigm depends on a series of
factors, including orthographic familiarity, degree of global lexical activity, and phonologic legality
of non-words.

© Copyright 1999 - 2017 ANT Neuro | www.ant-neuro.com | Terms of Use | Privacy Statement | Contact | USA Customers