An electrophysiological investigation of indirect semantic priming

Abstract

In two experiments, direct and indirect semantic priming were measured using event-related potentials. In Experiment 1, participants rated the relatedness between prime and target on a sevenpoint scale. In Experiment 2, participants simply read the primes and targets as they monitored for a semantic category in probe filler items. Significant direct and indirect N400 priming effects were observed in both experiments. In Experiment 1, the indirect N400 priming effect remained significant when indirectly related and unrelated word pairs were matched for participants' explicit relatedness judgments. In both experiments, the indirect N400 priming effects were preserved when indirectly related and unrelated word pairs were matched on more global and objective measures of semantic similarity. These findings are discussed in the context of current theoretical models of semantic memory and semantic priming. KeywordsERP; N400; semantic; memory; priming It has long been established that reaction times are decreased to words preceded by semantically related words ("tiger"-"stripes") in comparison with words preceded by semantically unrelated words ("truck"-"stripes"). This is known as the semantic priming effect. One of the mechanisms often invoked to explain this effect is an automatic spread of activation through semantic memory. In this model, semantic memory is conceptualized as a network of words or concepts (Anderson, 1983;Collins & Loftus, 1975). If an individual sees or hears a word (e.g., "tiger"), its node in semantic memory will be activated, and this activation will automatically spread from this node to those of related concepts (e.g., "stripes"). If the target word corresponding to this partially preactivated or primed node is then presented, the individual's response to that target will be facilitated. Despite the theoretical importance of this model, clear evidence for the spread of activation through semantic memory is still lacking, and several other candidate mechanisms-some controlled and some automatic-have been proposed to account for the semantic priming effect.The two controlled or strategic processes most often discussed in the context of semantic priming tasks are expectancy generation and semantic matching. In expectancy generation, the participant internally generates predictions about which word will appear next, and priming results from the target being a member of this expectancy set. In semantic matching, the participant consciously utilizes the relationship between the word pairs to bias decision making Address reprint requests to: Donna A.

An Event-Related Brain Potential Study of Direct and Indirect Semantic Priming in Schizophrenia

“…We predicted that in the comparison subjects, at both asynchronies, N400 would be largest (most negative) in response to unrelated targets, intermediate following indirectly related targets, and smallest after directly related targets, a pattern consistent with previous findings (16,26,27). Furthermore, we hypothesized that if schizophrenia is accompanied by broader spread of activation to weaker associates at short stimulus-onset asynchronies, then at the 300-msec asynchrony, prime words would activate indirectly related targets more strongly in patients than in comparison subjects, resulting in smaller N400 amplitudes following these targets in the patients.…”

Electrophysiological correlates of automatic spreading of activation in patients with psychotic disorder and first-degree relatives

“…In a typical lexical decision task, the N400 amplitude increases (i.e., becomes more negative) with semantic distance (more negative in the unrelated condition compared to the related condition) (Weisbrod et al, 1999). This N400 effect was also found with indirect associations under automatic timing processes, albeit to a lesser degree compared to associative relations, suggesting that the N400 is sensitive to automatic spreading of activation processes (Kreher et al, 2006;Weisbrod et al, 1999).…”

Semantic Priming in a Cortical Network Model

“…Such indirect prime-target relationships typically give rise to significant priming effects (Kreher, Holcomb, & Kuperberg, 2006;Bennett & McEvoy, 1999;Kiefer, Weisbrod, Kern, Maier, & Spitzer, 1998;Livesay & Burgess, 1998;Weisbrod, Maier, Harig, Himmelsbach, & Spitzer, 1998;Sayette, Hufford, & Thorson, 1996;Spitzer, Braun, Maier, Hermle, & Maher, 1993;McKoon & Ratcliff, 1992;McNamara, 1992;Shelton & Martin, 1992;McNamara & Altarriba, 1988;Ratcliff & McKoon, 1988;; Motes, personal communication, for a metaanalysis; but see de Groot, 1983).…”