Electrophysiological signatures of visual lexical processing: open- and closed-class words

• Published in: Journal of cognitive neuroscience Vol. 11; no. 3; p. 261
• Main Authors: Brown, C M, Hagoort, P, ter Keurs, M
• Format: Journal Article
• Language: English
• Published: United States 01-05-1999
• Subjects: Adult; Electroencephalography; Female; Humans; Male; Pattern Recognition, Visual - physiology; Psycholinguistics; Reaction Time - physiology; Reading; Scalp - physiology; Visual Perception - physiology
• ISSN: 0898-929X
• DOI: 10.1162/089892999563382

This paper presents evidence of the disputed existence of an electrophysiological marker for the lexical-categorical distinction between open- and closed-class words. Event-related brain potentials were recorded from the scalp while subjects read a story. Separate waveforms were computed for open- and closed-class words. Two aspects of the waveforms could be reliably related to vocabulary class. The first was an early negativity in the 230- to 350-msec epoch, with a bilateral anterior predominance. This negativity was elicited by open- and closed-class words alike, was not affected by word frequency or word length, and had an earlier peak latency for closed-class words. The second was a frontal slow negative shift in the 350- to 500-msec epoch, largest over the left side of the scalp. This late negativity was only elicited by closed-class words. Although the early negativity cannot serve as a qualitative marker of the open- and closed-class distinction, it does reflect the earliest electrophysiological manifestation of the availability of categorical information from the mental lexicon. These results suggest that the brain honors the distinction between open- and closed-class words, in relation to the different roles that they play in on-line sentence processing.