The paper considers the history of development and different aspects of the new neuropsychological theory of social brain, its relations with Luria’s and Vygotsky’s understanding of humans as a social and biological unity. Different theoretical models of analyzed. Experimental studies of influence of brain damages on social cognition and social behavior are described. Social features of child early development are of primordial value for understanding of social brain. This understanding is closely related to the important theory of developmental psychology, proposed by P. Galperin, underlying a double interaction between morphological and functional development. It is proved by negative consequences of child social deprivation on his brain development as well as by evidences of cultural differences in neuropsychological assessment. New understanding of social brain is proposed to be social and cultural determination and regulation of brain functioning.