>Becoming a parent in early 30s is common. Retiring in late 60s. If you make it, becoming too infirm in body to get around in 80s. These seem like brain chang

>Becoming a parent in early 30s is common. Retiring in late 60s. If you make it, becoming too infirm in body to get around in 80s. These seem like brain changes at these transitions are more likely to be effects rather than causes.