[Two semantic brain systems for rapid and slow differentiation of the abstract and concrete words].

In the previous studies, semantic processing was repeatedly found to be reflected in the late (300-800 ms) components of event-related potentials (ERP). However, a human may catch the meaning of the words much earlier. In this work we investigated brain mechanisms of semantic analysis of abstract and concrete written words in four experimental conditions: (1) simple reading (a subjects had to read words to him/herself); (2) simple classification (a subjects had to classify presented words into abstract and concrete categories); (3) cued and (4) uncued selective classification conditions (a subject had to classify only the words typed in a particular color).

[Dipole models for the sources of late evoked potential components in verbal tasks for intermodal attention and memory in humans].

In this paper we aimed at studying brain structures involved in intermodal attention and memory processes. This was accomplished by dipole modeling of the difference waves of event-related potentials recorded during the performance of verbal tasks and in the control condition. The models were constructed independently from each other for six difference waves obtained by subtracting different experimental conditions.

[Selective attention and memory: evoked potentials in visual and auditory verbal competition].

The brain mechanisms of the selective verbal attention were studied using evoked potential (EP) technique. It was shown that the late "cognitive" EP components (400-800 ms) related to memory function were more positive to the words presented via a relevant sensory channel and more negative to irrelevant words. The hypothesis is advanced that words delivered via two competing sensory channels, such as visual and auditory, are perceived, i.

[Dynamics of spectral characteristics of theta- and alpha-range EEG during negative emotional reactions].

Power characteristics of the EEG theta and alpha rhythms were studied in a human in neutral state and during a conditioned negative emotional reaction (Fp1, Fp2, F3, F4, C3, C4, P3, P4, O1, O2, F7, F8, T3, T4, T5, and T6 derivations). A significant increase in the relative spectral power in the narrow theta band of 7.4-8.