[Attempt to evaluate the bioelectrical function of the brain and the mental development of twin pregnancy children (author's transl)].

EEG records and psychological examinations were performed in 30 twin pairs, 9 of which were monozygotic and 21--dizygotic twins, aged 1 to 13 years. No data on disturbances in C.N.S. functions or somatic diseases were found on the basis of anamnesis in 5 pairs, but in 25 pairs the abnormalities were stated in the perinatal period febrile and infantile convulsions and head injury were also found. Normal EEG records were found in 5 pairs; in 6 pairs one of the children showed a normal record, while the other--an abnormal one, and in the remaining 19 pairs abnormal records were found (Table I). Totally similar EEG records were found in 11 pairs, and dissimilar ones in 19 pairs. The development quotient (D.Q.) or intelligence quotient (I.Q) amounted to 80-90 points in only 5 children, while in the others there was 90-110 and over. In 18 pairs the quotient values were similar, and in 12 pairs different (Table II). In pairs with equal values of the quotients qualitative differences were found in the functions measured. The similarities and differences in EEG records and also in D.Q. and I.Q. For monozygotic and dizygotic twins are illustrated by Table III. The authors analysed the similarities and differences in EEG records and D.Q. and I.Q. in twin pairs in relation to two groups of children. Group I includes 5 pairs of twins without data on C.N.S. function disturbances and group II--25 pairs in which there were factors which could damage the function of C.N.S. A predominance of similar EEG records and of similar values of quotients was found, in the I group irrespective whether they were monozygotic or dizygotic twins (Table IV). In group II, however, there were considerably less similar EEG records and similar quotient values and, moreover, qualitative differences were found in the functions measured. Similarities in monozygotic twins in opposition to the dizygotic ones were found in EEG records (Table V). The authors state that, despite the predominance of abnormal EEG records in the examined twins, no mental deficiency was found in any of the children. The EEG records differed more in the twins than the psychomotor development quotients, but similarities in the records were greater than those of the quotients in monozygotic twins. Concomitantly with similar numerical values of psychomotor development quotients there were qualitative differences of the functions measured. The greatest differences in EEG records and quotient values were found in pairs of twins in which data were found on factors which could disturb the function of the C.N.S. as well as in dizygotic twins.