ABSTRACT
An important point made in Chapter 3 is that the influence of rewards and costs depends upon person factors. Two sets of person factors are cognition and personality. Another set is biological. In general, biological factors have received little attention within criminology, but they have been very important in psychology. This chapter examines how what we are born with interacts with the environment to shape behavior. Interactions also explain why some person characteristics are risk/need factors and others may be strength factors. For example, opportunistic rewards for criminal behavior may be more appealing to the individual with low self-control (a risk/need factor), whereas high self-control serves as a strength or protective factor against the very same opportunistic rewards for crime.
A particular interest in this chapter is the life-course-persistent youths. They form a small subset of justice-involved youth (less than 10 percent) but they overwhelmingly commit most of the crimes. Genetic and neurophysiological factors play an important role for those on the life-course-persistent trajectory but environmental influences cannot be underestimated, as evidenced in the following chapters. Biological factors are the foundations for personality and cognitive formation.
