Theta Responses Are Involved in Lexical—Semantic Retrieval during Language Processing

• Published in: Journal of cognitive neuroscience Vol. 17; no. 3; pp. 530 - 541
• Main Authors: Bastiaansen, Marcel C.M., Linden, Marieke van der, Keurs, Mariken ter, Dijkstra, Ton, Hagoort, Peter
• Format: Journal Article
• Language: English
• Published: One Rogers Street, Cambridge, MA 02142-1209, USA MIT Press 01.03.2005; MIT Press Journals, The
• Subjects: Adult; Analysis of Variance; Behavioral psychophysiology; Biological and medical sciences; Brain - physiology; Brain Mapping; Cognition & reasoning; Electroencephalography - methods; Electrophysiology; Female; Fundamental and applied biological sciences. Psychology; Humans; Language; Language Tests; Male; Mental Recall - physiology; Neurology; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Reading; Speech Perception - physiology; Theta Rhythm; Time Factors; Human; Beta rhythm; Temporal lobe; Alpha rhythm; Hemispheric specialization; Lexicon; Electrophysiology; Cognition; Electroencephalography; Language; Semantics; Theta rhythm; Laterality
• ISSN: 0898-929X; 1530-8898
• DOI: 10.1162/0898929053279469

Oscillatory neuronal dynamics, observed in the human electroencephalogram (EEG) during language processing, have been related to the dynamic formation of functionally coherent networks that serve the role of integrating the different sources of information needed for understanding the linguistic input. To further explore the functional role of oscillatory synchrony during language processing, we quantified event-related EEG power changes induced by the presentation of open-class (OC) words and closed-class (CC) words in a wide range of frequencies (from 1 to 30 Hz), while subjects read a short story. Word presentation induced three oscillatory components: a theta power increase (4–7 Hz), an alpha power decrease (10– 12 Hz), and a beta power decrease (16–21 Hz). Whereas the alpha and beta responses showed mainly quantitative differences between the two word classes, the theta responses showed qualitative differences between OC words and CC words: A theta power increase was found over left temporal areas for OC words, but not for CC words. The left temporal theta increase may index the activation of a network involved in retrieving the lexical semantic properties of the OC items.