HUMAN-BRAIN GROWTH IN THE 19TH AND 20TH-CENTURY

Data of 2399 brain weights and ages from populations before 1880, 1885 to 1900 and 1966 to 1976 were obtained from German anatomical and pathological institutes, analyzed with non-linear and multiple linear regression analyses and the results compared. The influence of the absolute age (sample period) on brain weights of adults (age of at least 10 years of ontogenesis) could not be verified. Different averages in the different samples seem to be stipulated by inhomogeneities of the age distributions. Sex differences were confirmed for the different periods. There is an accelerated degree of maturity of brain weights between the population sampled from 1966 to 1976 and the two older populations. The growth rate of the degree of maturity reveals the same fact, i.e., the growth rate is more rapid than 100 years ago. These differences may be explained by changed causes of death in the autopsy samples, but it is possible that they are at least partly caused by an acceleration of brain development in the early postnatal period. In all populations analyzed brain weights in females develop faster than in males. The development of the brain weight in 6 more samples is compared with the results for the Medical School Hannover sample. © 1979.