Many Catholic religious orders are participating in a long range Alzheimer's disease study. Rush University's Religious Orders Study began in 1993 and tracks the participants' mental abilities through yearly memory testing. In addition to the annual tests, the study subjects agree to donate their brains. From the article: "The researchers sought members of religious orders, hoping they would be willing to donate and would not have children or spouses interfering with that arrangement at the last minute. More than 1,100 nuns, priests and brothers across the country representing a wide range of ethnic groups are taking part."