Аннотация:Background and aims: Human mnestic activity is mediated by different kinds of external signs. The ability for mediation depends on the activity of specific brain structures. The study aimed to reveal cerebral mechanisms related to various cues in visuo-spatial working memory. Method: 17 subjects aged from 22 to 35 years had to memorize the pattern of movements of the visual stimulus in the 3x3 square matrix. There were five conditions of memorization: 2 without mediation, 1 mediated by numbers in each square of the matrix, 1 mediated by images and 1 mediated by short words. During the tests, EEG (21 channels, monopolar) was registered. We calculated averaged ERPs of all subjects for each part of the test and stimuli type. Each individual ERP was presented as a number of equivalent dipole sources, located in brain structures, according to Talairach Atlas labels (Vartanov, 2002). Results: All three types of mediation improved remembering of spatial information. All participants showed maximum memory capacity in case when memorizing was mediated by numeric cue. In comparison with numeric mediation, word and image mediation presented two different patterns of brain activity, estimated as a number of activated structures. In case of word and images mediation brain activity was relatively higher in the right hemisphere, while in case of numeric mediation the left hemisphere was more activated. It can be suggested, that increased activation of left hemisphere demonstrates the processes of encoding spatial information into successive form, which provides the efficiency of numeric mediation. Conclusion: Numbers structures, which are frequently used in human practice, increase brain activity and improve memory capacity.