Middle-aged school-children were examined with learning disabilities, differentiated by the parameters of probabilistic prognosis in two subgroups: with disturbances of attention (1) and memory (2). The first subgroup differed from the norm by intensified reaction of desynchronization of the projection areas of the cortex to irrelevant stimuli. Relevant information evoked an increase of activation of the associative zones, less expressed than in the norm. In the second subgroup a weak involvement of associative cortical areas in the reaction of desynchronization to relevant stimuli correlated with insufficient formation of alpha 2-rhythm and high frequency of meeting the signs of dysfunction of mesodiencephalic brain structure. The results are discussed in the aspect of the role of neurophysiological mechanisms of regulation and trace fixation for the formation of the integrative brain activity in the ontogenesis.