HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Kiefer, M. Search for Related Content PubMed PubMed Citation Articles by Kiefer, M.

Repetition-priming Modulates Category-related Effects on Event-related Potentials: Further Evidence for Multiple Cortical Semantic Systems

University of Ulm, Germany

In the present study, the significance of category-related brain activations as an index of semantic memory structure was assessed within a repetition-priming paradigm during a lexical decision task. The interpretation of category-related effects has been debated since previous studies observed category-related brain activity mainly in tasks requiring explicit semantic categorization. Furthermore, categories were frequently associated with behavioral performance differences, which could have influenced the pattern of brain activation. Event-related potentials (ERPs) to words denoting objects from artifactual (e.g., tools) and natural categories (e.g., animals) were recorded while subjects were presented with words and pseudowords as distracters, which were repeatedly presented. Category-related ERP differences emerged in the time window of the N400, an electrophysiological index of semantic processing, over occipito-parietal and fronto-central regions as well as in the following window of a late positive potential. Repetition priming modulated these category-related ERP effects whereas behavioral repetition priming (faster reactions to repeated words) was comparable for both categories. Differences in ERP repetition effects were specifically due to diminished category-related activity at repeated presentation. The present results show that category-related brain activation is not confined to tasks requiring explicit semantic categorization. Most importantly, the study demonstrates that category-related brain activation can be specifically modulated by repetition priming in the absence of corresponding behavioral performance differences. These findings therefore substantiate the significance of category-related brain activations as reflections of semantic memory structure and support the notion of multiple cortical semantic systems.

Key Words: Lexical decision task • semantic memory organization • category specificity • N400 • late positive complex • repetition priming • event-related potentials

This article has been cited by other articles:

				M. Kiefer, E.-J. Sim, B. Herrnberger, J. Grothe, and K. Hoenig The Sound of Concepts: Four Markers for a Link between Auditory and Conceptual Brain Systems J. Neurosci., November 19, 2008; 28(47): 12224 - 12230. [Abstract] [Full Text] [PDF]

				K. Hoenig, E.-J. Sim, V. Bochev, B. Herrnberger, and M. Kiefer Conceptual Flexibility in the Human Brain: Dynamic Recruitment of Semantic Maps from Visual, Motor, and Motion-related Areas J. Cogn. Neurosci., October 1, 2008; 20(10): 1799 - 1814. [Abstract] [Full Text] [PDF]

				P. M. Pexman, I. S. Hargreaves, J. D. Edwards, L. C. Henry, and B. G. Goodyear Neural correlates of concreteness in semantic categorization. J. Cogn. Neurosci., August 1, 2007; 19(8): 1407 - 1419. [Abstract] [Full Text] [PDF]

				M. Kiefer, E.-J. Sim, S. Liebich, O. Hauk, and J. Tanaka Experience-dependent Plasticity of Conceptual Representations in Human Sensory-Motor Areas. J. Cogn. Neurosci., March 1, 2007; 19(3): 525 - 542. [Abstract] [Full Text] [PDF]

				M. Kiefer and D. Brendel Attentional Modulation of Unconscious "Automatic" Processes: Evidence from Event-related Potentials in a Masked Priming Paradigm. J. Cogn. Neurosci., February 1, 2006; 18(2): 184 - 198. [Abstract] [Full Text] [PDF]