Matching is not naming: A direct comparison of lexical manipulations in explicit and implicit reading tasks
Article first published online: 19 JUN 2012
Copyright © 2012 Wiley Periodicals, Inc.
Human Brain Mapping
Volume 34, Issue 10, pages 2425–2438, October 2013
How to Cite
Vogel, A. C., Petersen, S. E. and Schlaggar, B. L. (2013), Matching is not naming: A direct comparison of lexical manipulations in explicit and implicit reading tasks. Hum. Brain Mapp., 34: 2425–2438. doi: 10.1002/hbm.22077
- Issue published online: 12 SEP 2013
- Article first published online: 19 JUN 2012
- Manuscript Accepted: 13 FEB 2012
- Manuscript Revised: 1 FEB 2012
- Manuscript Received: 23 JUN 2011
- NIH. Grant Numbers: K02 NS0534425, ROIHD057076, NS61144, NS6144
- NSF IGERT. Grant Number: 0548890
The neurobiological basis of reading is of considerable interest, yet analyzing data from subjects reading words aloud during functional MRI data collection can be difficult. Therefore, many investigators use surrogate tasks such as visual matching or rhyme matching to eliminate the need for spoken output. Use of these tasks has been justified by the presumption of “automatic activation” of reading-related neural processing when a word is viewed. We have tested the efficacy of using a nonreading task for studying “reading effects” by directly comparing blood oxygen level dependent (BOLD) activity in subjects performing a visual matching task and an item naming task on words, pseudowords (meaningless but legal letter combinations), and nonwords (meaningless and illegal letter combinations). When compared directly, there is significantly more activity during the naming task in “reading-related” regions such as the inferior frontal gyrus (IFG) and supramarginal gyrus. More importantly, there are differing effects of lexicality in the tasks. A whole-brain task (matching vs. naming) by string type (word vs. pseudoword vs. nonword) by BOLD timecourse analysis identifies regions showing this three-way interaction, including the left IFG and left angular gyrus (AG). In the majority of the identified regions (including the left IFG and left AG), there is a string type × timecourse interaction in the naming but not the matching task. These results argue that the processing performed in specific regions is contingent on task, even in reading-related regions and is thus nonautomatic. Such differences should be taken into consideration when designing studies intended to investigate reading. Hum Brain Mapp 34:2425–2438, 2013. © 2012 Wiley Periodicals, Inc.