The first error associated with the research linking brain structure to psychological functions relates to the idea that specific brain parts cause certain psychological functions. This is problematic because many different parts play various roles in specific psychological functions regardless of what “lights up” during MRI studies. Therefore, the perfect mapping of psychological functions does not exist. The second error relates to the idea that studying the brain can reveal everything there is to know about the development of people.
However, psychology is not the study of biological processes but rather of people who make certain decisions and act in certain ways. One cannot understand people on a meaningful level just by looking at the processes occulting in the brain. The third error is linked to the idea that genes predict how a person will develop psychologically.
Such reliance on hereditary transmission ignores such aspects as the environment in which a person is developing, which is crucial for predicting future behaviors. For instance, I have a friend who was adopted from a family of substance abusers, and the love and support of his adoptive parents helped him become a successful columnist for an online magazine.