Secular Changes of the Main Head Dimensions in Japanese

Secular trends of length, breadth and circumference of the head in Japanese males were studied. Height and weight were added for comparison. A sample of 892 boys and adults ranging in age from 13 to 22 years from various educational institutions in Tokyo was measured. The data indicated that the present sample had somewhat larger heads and bodies than their predecessors 20 to 50 years ago. Brachycephalization seems to have been progressing for these 50 years in Japanese. It is due to a distinct increase in the breadth of the head (6.8 mm), not to a decrease of the length. The dimensions of the head in Japanese males are not stable and show some changes of the sort which have occured in some other populations of the world. Further, age changes of these dimensions were also considered. Without exception there was a tendency for mean values to decrease appreciably after 18 to 20 years of age, which, it is suggested is a result of the influence of the war reported by many authors for height and weight