The N400 in lexical access and in sentence processing

Aniela Improta França

Federal University of Rio de Janeiro, Brazil

The first event-related brain potential studies of linguistic stimuli appeared in the 1980’s reporting the N400, a negative-going wave, whose enlarged amplitude was believed to indicate frustration of a linguistic expectation during processing: ‘I prefer my coffee with socks’ (Kutas & Hillyard, 1980a). It also became clear from the early studies that this ERP seems to appear in relation to the access of any word, be it congruous or incongruous, surprising or plain, but the wave amplitude would be significantly increased when it is related to a semantically incongruous or unexpected word (Kutas & Hillyard, 1980b). Following the classical N400 tests, a myriad of linguistic ERP studies started being developed in different natural languages exploring different aspects of the wave up to the years around 2000 (Kutas & Hillyard 1982 1983, 1984; Van Petten & Kutas 1990; Osterhout & Holcomb 1992; Van Petten 1993; Federmeier & Kutas 1999a, b, 2001). There have been reported findings of N400 related both to lexical access and to sentence processing in several experimental protocols. Nowadays, these studies are recognized as a crucial tool in tracking the architecture of language, by testing precise theoretical hypotheses, which reveal a detailed chronology of computations involved in lexical access and in sentence processing (Friederici & Frisch 2000; Gomes & França 2008; Pylkkänen, Stringfellow & Marantz 2002; Pylkkänen & Marantz 2003; Pylkkänen & McElree 2007; Lau et al. 2006, 2009). For instance, lexical access studies relate modulations in the N400 to three main factors: (i) lexical frequency, (ii) phonological similarity versus morphological identity: spin-spinach, versus spin-spinning or (iii) semantic relatedness: pork-beef. In contrast, sentence processing studies propose that the N400 is a measure of syntactic integration, which on its turn is modulated by one more factor: (iv) the level of semantic predictability of verb selection. Granted these very different factors cited in the literature, the field of N400, in its state of the art, still lacks a unified reasoning: is the N400 related to the context available for the access of lexical information in the memory or does it relate with syntactic integration efforts that are in action after lexical access (Gomes & França 2008)? These are the questions this study aims at addressing by testing a set of stimuli distributed into three lexical access and three sentence processing conditions, all of them using the same noun as target. The idea is to verify what is modulating the N400, when the target noun is rejected, accepted or strongly anticipated both for the lexical and for the sentential conditions.

References

Kutas, M. & Hillyard, S. A. (1980a). Reading between the lines: Event-related brain potentials during natural sentence processing. Brain and Language, 11(2), 354–373.

Kutas, M. & Hillyard, S. A. (1980b). Reading senseless sentences: Brain potentials reflect semantic incongruity. Science, 207, 203–205.

Kutas, M. & Hillyard, S. A. (1982). The lateral distribution of event-related potentials during sentence processing. Neuropsychologia, 20(5), 579-590.

Kutas, M. & Hillyard, S. A. (1983). Event-related brain potentials to grammatical errors and semantic anomalies. Memory and Cognition, 11(5), 539-550.

Kutas, M. & Hillyard, S. A. (1984). Brain potentials reflect word expectancy and semantic association during reading. Nature, 307, 161-163.

Federmeier K. D. & Kutas M. (1999a) A Rose by Any Other Name: Long-Term Memory Structure and Sentence Processing. Journal of Memory and Language, 41, 469–495.

Federmeier K. D. & Kutas M. (1999b) Right words and left words: Electrophysiological evidence for hemispheric differences in meaning processing. Cognitive Brain Research, 8, 373–392.

Friederici A. D. & Frisch S. (2000) Verb Argument Structure Processing: The Role of Verb-Specific and Argument-Specific Information. Journal of Memory and Language, 43(3), 476–507.

Gomes, J. N. & França, A. I. (2008). A direcionalidade no relacionamento semântico: um estudo de potênciais bioelétricos relacionados a eventos lingüísticos (ERP). VEREDAS ON-LINE – Psicolinguística, 2, 167-171.

Lau, E.F., Stroud, C., Plesch, S., & Phillips, C. (2006). The role of structural prediction in rapid syntactic analysis. Brain and Language, 98, 74-88.

Lau, E, Almeida, D, Hines, P. C., & Poeppel, D. (2009). A lexical basis for N400 context effects: Evidence from MEG. Brain and Language, 111(3), 161–172. doi:10.1016/j.bandl.2009.08.007.

Osterhout L. & Holcomb P. J. (1992). Event-related brain potentials elicited by syntactic anomaly. Journal of Memory and Language, 31, 785–806.

Pylkkänen L., Stringfellow A., & Marantz A. (2002). Neuromagnetic evidence for the timing of lexical activation: An MEG component sensitive to phonotactic probability but not to neighborhood density. Brain and Language, 81, 666–678.

Pylkkänen L. & Marantz A. (2003). Tracking the time course of word recognition with MEG. Trends in Cognitive Science, 7(5), 187–189.

Pylkkänen L. & McElree B. (2007). An MEG Study of Silent Meaning. Journal of Cognitive Neuroscience, 19(11), 1905–1921.

Van Petten C. & Kutas M. (1990). Interactions between sentence context and word frequency in event-related brain potentials. Memory & Cognition, 18(4), 380–393.

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