Association for Behavior Analysis International

Humans are a striking anomaly in the natural world. While we are similar to other mammals in many ways, our behavior sets us apart. Our unparalleled ability to adapt has allowed us to occupy virtually every habitat on earth using an incredible variety of tools and subsistence techniques. Our societies, heavily regulated by culturally transmitted institutions, are larger, more complex, and more cooperative than any other mammal's. In this talk, Richerson will argue that the key to understanding human behavior is a theory of cultural evolution and gene-culture coevolution that is built on Darwinian principles. Our ecological dominance and our singular social systems stem from a psychology uniquely adapted to create complex culture. Culture is neither superorganic nor the handmaiden of the genes. Rather, it is essential to human adaptation, as much a part of human biology as bipedal locomotion. Culture has played a leading rather than lagging role in human evolution. Culture creates novel environments than then act as forces of natural selection on genes. Most strikingly, our cooperative societies have led to something like the domestication of our genes.

To build a science of the person, the most basic question is: How can one identify and understand the psychological invariancethe basic coherence and organization-- that distinctively characterizes an individual and that underlies the variations in the thoughts, feelings, and actions that occur across contexts and over time? This question proved particularly difficult because discrepancies soon emerged between the expressions of consistency that were expected and those that were found. The resulting classic personality paradox became: How can we reconcile our intuitions---and theories---about the invariance and stability of personality with the equally compelling empirical evidence for the variability of the persons behavior across diverse situations? Which is right: the intuitions or the findings? I discuss some advances to answer this question since it was posed decades ago. These findings have allowed a resolution of the paradox, and provide the outlines for a conception of the underlying structure and dynamics of behavior, and its links to situations, that seems to better account for the data on consistencies and variability in the expressions of individual differences. This conception is applied to the analysis of self-control, focusing on the ability to delay gratification, and its determinants, development, and implications over the life course.

Male zebra finches learn a vocal pattern during juvenile life in a manner that bears a striking behavioral resemblance to human vocal learning. Following an early tutoring phase where the song of an adult male is heard, juvenile male zebra finches begin a sensory-motor learning phase where auditory feedback is used to shape initially variable vocal sounds into the sequence of distinct note types heard earlier in life. The neural circuit that controls this learning is composed of two neural pathways that converge on a common vocal/motor output. Here, I will present the view that the interaction between these two pathways is one of ontogenetic variation and selection. Interestingly, the neural pathway responsible for generating vocal variation includes the basal ganglia, a brain region highly conserved in architecture and neurochemistry across birds and mammals. Thus, our findings in songbirds suggest a broader model, where basal ganglia function contributes to the pre-existing behavioral variation necessary for operant learning to occur.

Advances in neurobiological techniques are occurring at an astonishing rate. In many respects, study of drug self-administration happens in a similar manner to the initial studies nearly 40 years ago. If the sophisticated techniques available to neuroscience are to be used to help understand drug self-administration (and potentially drug use in humans), help explain some of the interesting findings, or find biological correlates of behavioral changes, then the behavioral models used need to be equally as sophisticated, interesting and dynamic. Data from two series of experiments will be presented and discussed with reference to neurobiological correlates of the behavioral differences. In monkeys, social housing and the establishment of dominance hierarchies was used to induce neurobiological changes that were then associated with differences in cocaine self-administration. In rats, various histories of self-administration result in animals that, for example, respond to considerably higher breakpoints maintained by cocaine on a progressive ratio schedule, relative to control animals. Neurobiological investigation of these groups of rats can help find biological correlates related to changes in the reinforcing efficacy of cocaine (which might be related to the development of addiction in humans). The overall focus of the presentation will be to strengthen the idea the behavioral scientists need to continue developing interesting behavioral models if we are going to try to use some of the neurobiological and molecular biological techniques that are being developed in other fields of science.