[A neurophysiologic analysis of the solution of arithmetic problems by seven to eight-year-old schoolchildren].

The nature of correlation connections between various areas of the cerebral cortex in the process of solving arithmetic problems of different complexity was studied in children seven to eight years old. Particularly noticeable differences by this parameter became prominent between the following periods of solving easy and difficult problems: 1) presentation of the problems; 2) comparison of the solution with the control; 3) selfestimation of the result of the activity. An important part in each of the indicated periods was played by comparing the preceding and current excitations. When difficult problems were solved, this process ended in a discordance effect. The findings attest that the phenomenon of discordance in effecting purposeful activity produces activation of the brain as a whole and of its frontal areas in particular.