abstract Matthew Botvinick

Matthew Botvinick (Princeton Neuroscience Institute and Department of Psychology, Princeton University, U.S.A.)

The cost of control.

The Law of Less Work states that when two courses of behavior lead to the same terminal reward, there will be a preference for the less effortful course of behavior. This principle has been overwhelmingly validated in the case of physical effort. However, it has been also been widely assumed to hold for mental or cognitive effort. Although this idea has been used to explain a wide range of phenomena, there has been surprisingly little attempt to test it. Over the past several years, we've developed behavioral methods for studying the role of cognitive effort demands in decision making. The results collected so far provide clear validation for the notion that cognitive effort is subjectively costly. People will, in fact, forego monetary reward in order to avoid demands for mental effort, an effect that cannot be explained in terms of error avoidance or minimization of time on task. The form of effort involved appears to be linked specifically to the mobilization of executive functions or cognitive control. Through a series of fMRI studies, we have tied control costs to activation of regions within medial and lateral prefrontal cortex, and demonstrated an effect of control costs on subcortical reward processing. In the most recent phase of research, we have studied effort-based decision making through the lens of economic labor supply theory, and also investigated potential links between cognitive demand avoidance and individual differences in self-control. I will provide an overview of established findings, and highlight open questions.