Microstates in Language-Related Brain Potential Maps Show Noun–Verb Differences

Abstract

Brain processing of grammatical word class was studied analyzing event-related potential (ERP) brain fields. Normal subjects observed a randomized sequence of single German nouns and verbs on a computer screen, while 20-channel ERP field map series were recorded separately for both word classes. Spatial microstate analysis was applied, based on the observation that series of ERP maps consist of epochs of quasi-stable map landscapes and based on the rationale that different map landscapes must have been generated by different neural generators and thus suggest different brain functions. Space-oriented segmentation of the mean map series identified nine successive, different functional microstates, i.e., steps of brain information processing characterized by quasi-stable map landscapes. In the microstate from 116 to 172 msec, noun-related maps differed significantly from verb-related maps along the left-right axis. The results indicate that different neural populations represent different grammatical word classes in language processing, in agreement with clinical observations. This word class differentiation as revealed by the spatialtemporal organization of neural activity occurred at a time after word input compatible with speed of reading.

Face-elicited ERPs and affective attitude: brain electric microstate and tomography analyses

“…Coordinates in mm after Talairach and Tournoux (1988); origin at anterior commisure; X left (2) to right (1); Y posterior (2) to anterior (1); Z inferior (2) present study allowed the discrimination of sequential brain microstates as basic elements of brain information processing (Koenig and Lehmann, 1996;Koenig et al, 1998;Lehmann et al, 1998). The two microstates at 132±196 ms and at 196±272 ms after stimulus onset were systematically in¯uenced by the subjects' affective attitude towards the face images (assessed after the experiment).…”

“…Originally, predetermined window sizes were used (Lehmann and Skrandies, 1984;Lehmann, 1987). In the present study, a data-driven approach is used so that window size preselection is avoided (Koenig and Lehmann, 1996;Koenig et al, 1998). This approach involves three basic steps.…”

“…In the present study, temporal brain microstate segmentation (Koenig and Lehmann, 1996;Koenig et al, 1998;Lehmann et al, 1998) together with a new brain electric tomography approach: low resolution electromagnetic tomography (LORETA; Pascual-Marqui et al, 1994 allowed the assessment of the timing and cortical localization of personality-modulated, face-elicited processes, issues not covered in a previous analysis (Pizzagalli et al, 1998). The present study analyzed 27 channel event-related potential (ERP) ®elds recorded while subjects (dichotomized for their affective, approaching vs. withdrawing attitude towards faces) passively observed face images without tasks, i.e.…”

“…When examining the temporal development of sequences of momentary maps of potential distributions (landscapes of potentials) on the head surface, a recurrent observation is that these sequences consist of brief epochs of quasi-stable map con®gurations (landscapes), called microstates, that are concatenated by rapid transitions (e.g. Lehmann and Skrandies, 1984;Lehmann, 1987;Koenig and Lehmann, 1996;. Thus, brain electric ®eld characteristics change in a stepwise manner rather than steadily, although each step or microstate must consist of the activity of many parallel neuronal processes.…”

Natural world physical, brain operational, and mind phenomenal space–time

“…Furthermore, their studies have shown that these microstates are associated with different modes of spontaneous thoughts [270] or with spontaneous visual imagery, or abstract thinking [271].…”