Development of mechanisms of recognition fragmented images at the preschool and early school ages
Farber, D.A.; Petrenko, N.E.
Fiziologiia Cheloveka 38(5): 5-15
2012
ISSN/ISBN: 0131-1646 PMID: 23101235 Document Number: 656174
Psychophysical and electrophysiological indices of recognition of incomplete objects with progressive increasing of fragments, were studied in children of three age groups: 5-6, 7-8 and 9-10 years old. It is shown that most pronounced change in the effectiveness of recognition takes place between 5-6 and 7-8 years of age. In the group of children of 5-6, neither significant influence of the recognition process on ERP was found in the prefrontal cortex nor any significant growth of the Nd component was observed over extrastriate cortex. However, in the extrastriate cortex, the amplitude N170-200 component that reflects sensory analysis and encoding extracted features did increase. In the majority of children of this age, the immaturity of the prefrontal cortex manifest itself in the deficit of inhibitory control that results in the tendency to give the impulsive responses and make numerous errors. In children of 7-8, successful recognition is accompanied by the growth of the amplitude of N100 and N250 components over the prefrontal cortex and the growth of NcI component over the extrastriate cortex. In these children, when compared to the children of 5-6, a significant reduction, is observed in the error rate and the recognition threshold. By the age of 9-10 years, the growing role of the prefrontal cortex shows in greater gain in the Nd amplitude and the later ERP component that correspond to cognitive operations related to the recognition process. The results of the study point to the qualitative difference in the mechanisms of recognition between pre-school children and the younger school-children. At the age of 5-6, recognition is carried out on the basis of integration of sensory signs of objects. Since the 7-8 age, in recognition of fragmented images major role belongs to the prefrontal cortex, with its participation search of possible analogs of object in memory and the object identification is carried out.