Neural Substrates of Forward and Backward Associative Priming: A Functional MRI Study

Sarah Terrien,Laurent Pierot,Stéphanie Caillies,Chrystel Besche-Richard,Véronique Baltazart,Christophe Portefaix,Fabien Gierski

doi:10.4236/psych.2013.410a007

Abstract

Forward associative priming results of an association moves from the prime to the target whereas back- ward associative priming results of an association from the target to the prime (Koivisto, 1998). Little is known about this dissociation of process and the associated cerebral substrates. Fourteen healthy partici- pants were included in this study. The task consisted in a lexical decision task using an fMRI-adapted se- mantic priming paradigm. Contrasts between forward related and forward unrelated conditions showed activation in the left temporal gyrus, left inferior prefrontal cortex, fusiform gyrus and occipital regions and cerebellum. Investigation of the different patterns of activation between forward and backward prim- ing shows significant results: during the contrast between the forward priming effect and the backward priming effect, we observe a deactivation of BOLD response in temporal and frontal areas, which may re- flect the post-lexical integration process. So, areas responsible for language and for decoding spelling seem not to be involved in the backward process. An adaptation of this research in event-related brain po- tentials is underway to better explore the temporality of post-lexical process.

Highlights

Semantic priming is a well-described phenomenon in which a target word is recognized faster when it is preceded by a semantically related word than when it is preceded by an unrelated word (Meyer & Schvaneveldt, 1971; Neely, 1991)
Forward priming is presumably produced by pre-lexical processes, automatic spreading activation (ASA) at short stimulus onset asynchronies and expectancy generation (EG) at long ones (Franklin, Dien, Neely, Huber, &Waterson, 2007)
We studied forward semantic integration and backward semantic integration with an original semantic priming paradigm that had not previously been used in an functional magnetic resonance imaging (fMRI) study

Summary

Introduction

Semantic priming is a well-described phenomenon in which a target word (e.g., flower) is recognized faster when it is preceded by a semantically related word (e.g., tree) than when it is preceded by an unrelated word (e.g., knife) (Meyer & Schvaneveldt, 1971; Neely, 1991). Researchers have typically used the lexical decision task to observe the priming effect. In this task, a word (the prime) is presented visually for a fraction of a second, followed after a delay by a letter-string (the target). Backward associative priming occurs as a result of a strong associative link moving from the target to the prime, but not the other way around (Koivisto, 1998). It has been shown that backward priming requires a post-lexical process occurring when an association links the target to the prime but not vice versa, and may be due to SM and not to EG or ASA (Chwilla, Hagoort, & Brown, 1998; Kahan, Neely, & Forsythe, 1999)

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