Contraction of front and side parts -- as cells die off -- was observed in some subjects in their thirties, but it was still not evident in some sixty- and seventy-year-olds.

• 随着细胞的死亡，在一些30几岁研究对象的大脑前部和左右半球发现有收缩现象，但是，在一些60岁，甚至70岁的对象身上，这种现象并不明显。