Contributions of the prefrontal cortex to the neural basis of human decision making (Fragment)

Daniel C. Krawczyk*
Department of Psychology, University of California, Los Angeles

Abstract

The neural basis of decision making has been an elusive concept largely due to the many subprocesses associated with it. Recent efforts involving neuroimaging, neuropsychological studies, and animal work indicate that the prefrontal cortex plays a central role in several of these subprocesses. The frontal lobes are involved in tasks ranging from making binary choices to making multi-attribute decisions that require explicit deliberation and integration of diverse sources of information. In categorizing different aspects of decision making, a division of the prefrontal cortex into three primary regions is proposed. (1) The orbitofrontal and ventromedial areas are most relevant to deciding based on reward values and contribute affective information regarding decision attributes and options. (2) Dorsolateral prefrontal cortex is critical in making decisions that call for the consideration of multiple sources of information, and may recruit separable areas when making well defined versus poorly defined decisions. (3) The anterior and ventral cingulate cortex appear especially relevant in sorting among conflicting options, as well as signaling outcome-relevant information. This topic is broadly relevant to cognitive neuroscience as a discipline, as it generally comprises several aspects of cognition and may involve numerous brain regions depending on the situation. The review concludes with a summary of how these regions may interact in deciding and possible future research directions for the field.

Introduction

Decision making is required for behaviors ranging from simple movements to the complex consideration of multiple alternatives and reasoning about distant future consequences. The topic has long been studied in a variety of separate disciplines with an equally broad range of techniques, ranging from investigations of the neuronal correlates of binary choice in non-human primates to complex analyses of group decisions in applied settings. This breadth has resulted in a large gap so that research into the neural basis of decision making has often been limited to the simplest of decision processes and has remained largely disconnected from applications to complex human judgments, while high level decision research has remained heavily descriptive with theories of human decision making rarely making solid connections to neurophysiological underpinnings. Through recent efforts reviewed here, this state of decision research is beginning to change. Investigations over the last decade have begun to view decision making from the perspective of cognitive neuroscience and are closing this longstanding gap between the ends of the decision research spectrum. This review describes studies that have managed to move toward a greater understanding of the neural systems contributing to decision making, while also capturing some of the cognitive complexity and relevance to deciding in everyday life that had previously been strictly the domain of purely descriptive decision research. Viewing complex human decision making in terms of the neural processing that underlies its potentially numerous subprocesses may be a critical next step in the effort to understand human decision making and most critically the mechanisms behind why people decide in the ways they do. This unified approach has the potential to move theories of human decision making towards incorporating the effects that neural system interactions have on reasoning and deciding.