There are some famous studies that utilize study designs that we are learning about this week. Here is a glance at correlational studies that might be interesting to explore further. Remember a correlational study is one looking for a relationship between two variables. . Is there a biological basis for behavior? o Bouchard and Lykken conducted a study with identical twins separated at birth to look at nature versus nurture. . Does high stress cause more illness? o Holmes and Rahe conducted a study developed a Social Readjustment Rating Scale (SRRS) to look at high stress and illness