[Brain Organization of the Preparation for Visual Recognition in Preadolescent Children].

The brain organization of the process of preparation for the perception of incomplete images fragmented to different extents. The functional connections of ventrolateral and dorsoventral cortical zones with other zones in 10-11-year-old and 11-12-year-old children were studied at three successive stages of the preparation for the perception of incomplete images. These data were compared with those obtained for adults.

[The functional brain organization during preparation for recognizing incomplete images].

The functional interaction between prefrontal cortex and other cortices was analyzed during the pre-stimulus period in the task in which human subjects (n = 36) were asked to recognize a set of incomplete images of different degree of fragmentation. The imaginary part of the complex-valued coherency was used to measure a strength of inter-area coupling at the alpha-rhythm frequency. Based on the analysis of individual responses the two equal sub-groups (n = 13) showing the lowest and highest recognition scores were extracted from the whole group of subjects.

[On the age-related trends in using sensory information in movement organization].

In the present paper, two apparently contradictory developmental trends routinely found in developmental experimental studies are discussed. One of them is the reduction in relative usage of sensory information in movement control; the other (reverse) trend is that, along the course of development, the sensory information plays increasing role in movement organization. An analysis of experimental data suggests that these two trends can be considered as two mutually related overt consequences of the growing ability to build internal models of the processes in the external world and those within the motor system.

[Functional organization of the cerebral cortex during preparation to recognition of incomplete linedrawings in 7-8 years-old children and adults].

Functional interaction between prefrontal, temporal and tempo-parieto-occipital zones during preparation to recognition of incomplete linedrawings were analyzed in adults (n = 26) and children of 7-8 years old (n = 20). The strength of cortico-cortical interactions was estimated with the imaginary part of the complex-valued coherence at the frequency of alpha-rhythm (Jα). The Jα value was analyzed in the following three experimental conditions which corresponded to different stages of preparation to visual recognition: nonspecific sustained attention in the period preceding the cue (C1); focused attention in the period preceding a not-yet-recognized target stimulus (C2) and focused attention prior the successfully recognized stimulus (C3).

[Quantitative measures of cortical functional connectivity: a state-of-art brief survey].

This par reviews modern approaches to measuring cortical functional and effective connectivity in neurocognitive networks--the large-scale distributed systems of interacting neuronal populations which are thought to underlie the cognitive processing. Two broad classes of methods of connectivity estimation, linear and nonlinear, are discussed. In the class of linear methods, besides the coherence that is routinely used for measuring the strength of functional links, the vector autoregressive modeling of multichannel EEG is discussed in some details.