bornd005: April 2012 Archives

Looking back at what I have learned over the semester, one thing that comes to mind is the twin study that was conducted here at the University of Minnesota. In the study, 130 identical and fraternal twins were reunited after being separated immediately after birth and growing up in different families. When comparing the personalities of each twin, researchers found that identical twins who did not grow up together in the same environment were no more alike in personality than identical twins who did grow up in a shared environment. Researchers were able to conclude that shared environment plays very little role in the type of personality a person will have as an adult.

This finding was very surprising to me. I had always figured that how a person is raised and the type of environment that person is raised in would be a very important factor in determining a person's personality, but this is not the case. So when we want to claim that a person's personality is what it is because of how that person was raised as a child, we should think twice and consider other factors. The results also show the importance of genetic factors on personality, so we should also keep that in mind. I think the twin study is definitely something I'll remember five years from now.

Infants begin to form attachments to their parents very early on in life. Are these attachments simply made with those who provide nourishment for the infant, or are there other important factors to consider? Harry Harlow helped answer this question in a study he performed in the 1950s, which I find rather interesting. He used infant rhesus monkeys (which he separated from their mothers soon after birth) and placed them in a cage with two figures that represented their mothers. One of the mothers was made out of uncomfortable metal wires and had an angular face, but was also the source of nourishment and had a bottle of milk. The other mother was made out of a heated, comfortable terry cloth and had a rounded face, but did not have a bottle of milk.

Harlow found that the infant monkeys went to the wire mothers for milk, but spent more time with the mothers made of terry cloth. When the baby monkeys were confronted with a scary stimulus, most would attach themselves to the terry cloth mother. This was later called contact comfort, the positive emotions afforded by touch. So, while you may think nourishment plays the larger role in forming attachments, it is actually touch that has more of an effect. It is important to understand how important this bond is for infants and children.