Article

Linking semantic priming effect in functional MRI and event-related potentials

Graduate School of Environmental Studies, Nagoya University, Nagoya, Aichi, 464-8601, Japan.
NeuroImage (Impact Factor: 6.36). 03/2005; 24(3):624-34. DOI: 10.1016/j.neuroimage.2004.09.008
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ABSTRACT The aim of this study is to examine the neural substrates involved in semantic priming using a combined event-related functional magnetic resonance imaging (fMRI) and event-related potentials (ERP) study. Twelve subjects were instructed to judge whether the presented target word was a real word or a nonword. Under the related condition, target words were preceded by a semantically related prime word. On the other hand, under the unrelated condition, prime words did not have semantic relatedness with the target word. The reaction time for reaching a judgment was longer under the unrelated condition than under the related condition, indicating that the recognition of target words is promoted by semantic priming under the related condition. In the fMRI results, we found reduced activity in the dorsal and ventral left inferior frontal gyrus, the anterior cingulate, and left superior temporal cortex for related versus unrelated conditions (i.e., the repetition suppression effect). ERP analysis revealed that the amplitude of the N400 component was reduced under the related condition compared with the unrelated condition (i.e., the N400 priming effect). Correlation analysis between the BOLD repetition suppression effect and the N400 priming effect decomposed by independent component analysis (ICA) across subjects showed significant correlation in the left superior temporal gyrus. This finding is consistent with the recent MEG data suggesting that the source of N400 is judged to be the bilateral superior temporal lobe. We discussed this finding herein in relation to the modulation of access to the phonological representation caused by semantic priming.

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Available from: Tomohisa Okada, Sep 02, 2015
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    • "Following the timing of a previous study (Gold et al., 2006) which used short SOA (study 2) and long SOA (study 3) separately to emphasize early and late stages of word recognition, we also employed a short SOA of 150 ms and a long SOA of 600 ms. Following previous studies (Matsumoto et al., 2005; Rissman, Eliassen, & Blumstein, 2003), we used 600 ms as long SOA to ensure that stimuli would be presented within an appropriate time frame for TMS. A schematic is shown in Fig. 1A. "
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    Brain and Cognition 11/2014; 93. DOI:10.1016/j.bandc.2014.11.002 · 2.68 Impact Factor
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    • "Supraliminal semantic priming, which also involves controlled semantic mechanisms such as a comparison of the meaning of the prime and the target word (semantic matching) in addition to automatic semantic processing (Neely, 1991), modulated activity also in brain regions other than vOT. The regions varied widely across studies and included the superior and the middle temporal gyri (Copland et al., 2003; Giesbrecht et al., 2004; Gold et al., 2006; Kotz et al., 2002; Matsumoto et al., 2005; Rissman et al., 2003; Wible et al., 2006), as well as the inferior and the middle frontal gyri (Copland et al., 2003; Giesbrecht et al., 2004; Kotz et al., 2002; Matsumoto et al., 2005; Rissman et al., 2003; Wheatley et al., 2005; Wible et al., 2006). It has therefore been suggested that vOT reflects automatic semantic activation whereas other temporal and frontal areas support controlled semantic processing (Ulrich et al., 2013). "
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    • "Furthermore, to investigate the relationship between the fMRI and ERP activations, we calculated correlations of the experimental effect in the identified ERP sources with those from selected fMRI clusters, similar to the approach taken by Matsumoto and colleagues [16]. Following their procedure, we calculated the differences between mean activations to unrelated vs. related primes (semantic effect), and additionally, we calculated the unrelated vs. identical difference (identity effect). "
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