Prestimulus EEG microstates influence visual event-related potential microstates in field maps with 47 channels

Abstract

The influence of the immediate prestimulus EEG microstate (sub-second epoch of stable topography/map landscape) on the map landscape of visually evoked 47-channel event-related potential (ERP) microstates was examined using the frequent, non-target stimuli of a cognitive paradigm (12 volunteers). For the two frequent prestimulus microstate classes (oriented left anterior-right posterior and right anterior-left posterior), ERP map series were selectively averaged. The post-stimulus ERP grand average map series was segmented into microstates; 10 were found. The centroid locations of positive and negative map areas extracted as landscape descriptors. Significant differences (MANOVAs and t-tests) between the two prestimulus classes were found in four of the ten ERP microstates. The relative orientation of the two ERP microstate classes was the same as prestimulus in some ERP microstates, but reversed in others. Thus, brain electric microstates at stimulus arrival influence the landscapes of the post-stimulus ERP maps and therefore, information processing; prestimulus microstate effects differed for different post-stimulus ERP microstates.

Right parietal brain activity precedes perceptual alternation during binocular rivalry

“…Since this activation pattern changes about every 100 ms, we assume that the momentary state just within the 100 ms around the stimulus is most crucial for determining the fate of the stimulus. Previous studies support this hypothesis [Britz et al, 2009;Kondakor et al, 1995Kondakor et al, , 1997Lehmann et al, 1998;Mohr et al, 2005].…”

“…As the average duration of a microstate is about 100 ms and the arrival of a stimulus does not ''disrupt'' a momentary microstate, we reasoned that the GFP maximum in the 50 ms before the onset is the best representative of the microstate immediately before the stimulus onset. We thus extracted the map representing the momentary scalp topography of the GFP maximum in the 50 ms before stimulus onset that was temporally closest to the stimulus onset as the representative of the pre-stimulus microstate in each trial [Britz et al, 2009;Kondakor et al, 1995Kondakor et al, , 1997Lehmann et al, 1994;Mohr et al, 2005].…”

Brain State-dependent Functional Hemispheric Specialization in Men but not in Women

“…In earlier studies, it has been shown that FBS influence subsequent information processing as evidenced by differences in visual (Konda´kor et al, 1995(Konda´kor et al, , 1997 and auditory (Lehmann et al, 1994) event-related potentials. In these studies, FBS were defined electrically in terms of systematic topographic differences in global scalp electric potentials.…”

“…In a last step, these FBS maps were further grouped together on the basis of the position of the positive and negative extrema of the FBS map. Based on previous studies (Lehmann et al, 1994;Konda´kor et al, 1995Konda´kor et al, , 1997, two classes were defined, one class having a left anterior--right posterior location of the extrema (LA-RP map) and the other class having a right anterior--left posterior position of the extrema (RA-LP map).…”

“…These momentary states, when defined as periods of topographic stability of the electric potentials, last for~80--150 ms and presumably correspond to spontaneous coherent functional microstates of the brain (Lehmann, 1987;Wackermann et al, 1993;Koenig et al, 2002). In previous work, Lehmann and collaborators (Lehmann et al, 1994;Konda´kor et al, 1995Konda´kor et al, , 1997 have classified these functional microstates just prior to stimulus presentation and calculated separate evoked-potentials for each class. The authors showed that stimulus-evoked potentials drastically varied as a function of such different classes of functional microstates at stimulus arrival, independent of task complexity.…”