An examination of the relationship between the brain and culpability that offers a comprehensive neuroscientific theory of human responsibility. When we praise, blame, punish, or reward people for their actions, we are holding them responsible for what they have done. Common sense tells us that what makes human beings responsible has to do with their minds and, in particular, the relationship between their minds and their actions. Yet the empirical connection is not necessarily obvious. The “guilty mind” is a core concept of criminal law, but if a defendant on trial for murder were found to have serious brain damage, which brain parts or processes would have to be damaged for him to be considered not responsible, or less responsible, for the crime? What mental illnesses would justify legal pleas of insanity? In Responsible Brains , philosophers William Hirstein, Katrina Sifferd, and Tyler Fagan examine recent developments in neuroscience that point to neural mechanisms of responsibility. Drawing on this research, they argue that evidence from neuroscience and cognitive science can illuminate and inform the nature of responsibility and agency. They go on to offer a novel and comprehensive neuroscientific theory of human responsibility. The authors' core hypothesis is that responsibility is grounded in the brain's prefrontal executive processes, which enable us to make plans, shift attention, inhibit actions, and more. The authors develop the executive theory of responsibility and discuss its implications for criminal law. Their theory neatly bridges the folk-psychological concepts of the law and neuroscientific findings.

Some neurological patients exhibit a striking tendency to confabulate—to construct false answers to a question while genuinely believing that they are telling the truth. A stroke victim, for example, will describe in detail a conference he attended over the weekend when in fact he has not left the hospital. Normal people, too, sometimes have a tendency to confabulate; rather than admitting "I don't know," some people will make up an answer or an explanation and express it with complete conviction. In Brain Fiction , William Hirstein examines confabulation and argues that its causes are not merely technical issues in neurology or cognitive science but deeply revealing about the structure of the human intellect. Hirstein describes confabulation as the failure of a normal checking or censoring process in the brain—the failure to recognize that a false answer is fantasy, not reality. Thus, he argues, the creative ability to construct a plausible-sounding response and some ability to check that response are separate in the human brain. Hirstein sees the dialectic between the creative and checking processes—"the inner dialogue"—as an important part of our mental life. In constructing a theory of confabulation, Hirstein integrates perspectives from different fields, including philosophy, neuroscience, and psychology to achieve a natural mix of conceptual issues usually treated by philosophers with purely empirical issues; information about the distribution of certain blood vessels in the prefrontal lobes of the brain, for example, or the behavior of split-brain patients can shed light on the classic questions of philosophy of mind, including questions about the function of consciousness. This first book-length study of confabulation breaks ground in both philosophy and cognitive science.