Background: 

In real life we often have to recognize incomplete images and perform mental gathering of whole image from separate details. Considering gender differences in perception of global and local features of objects, we have investigated gender specificity of cortical visual hierarchy in processing of complex figure and its details. Methods. In 32 healthy adults (12 females) visual event-related potentials were studied under observation of whole and ungrouped images. Every image was represented as whole one and as four levels of ungrouping to details of different complexity. Evoked potentials were recorded from visual areas [Ocy]1/[Ocy]2, [Rcy][Ocy]1/[Rcy][Ocy]2, [Rcy]3/[Rcy]4 and [Tcy]5/[Tcy]6. Results. In males the P1 amplitude increased in symmetrical occipital, parietal and left inferior temporal areas parallel to ungrouping of observed images. In parietal areas P1 responsiveness was asymmetrical: in the left area P1 enhancement was related with the simplification of observed elements, when in the right area the displacement of elements was more important for P1 increase. In females, the sensitivity to ungrouping was revealed at later stages of visual processing. The N1 amplitude decreased during perception of more simple elements as compared to the whole image locally in right inferior temporal area. The P3 amplitude under stimulus ungrouping increased irrespectively of subjects' gender. Furthermore in males the image ungrouping evoked the decrease of correlation between frontal and visual cortical areas and between different visual areas. Conclusion. The revealed data suggest gender specificity in processing of whole images and their elements and presumably the higher cortical specialization of this operation in males as compared with females.