A neural signature of the current self*

Because the self is such a familiar part of everyday experience, it is easy to take its existence for granted. However, upon reflection it becomes apparent just what a puzzle this aspect of human psychology is. From a series of fleeting moments of consciousness individuals construct a notion of the self as a distinct entity that persists across time from the past to the present and into the future. How and why do people do this? Such questions have intrigued psychologists since the beginning of the discipline (James, 1890/1950) and others long before (Locke, 1690/1979; Hume, 1739/1975; Kant, 1798/1974). Modern psychology has used a range of theoretical approaches and a variety of methodologies in an attempt to understand the self. For example, relevant to the question of how the self comes to be defined as a distinct entity, research has investigated the neural systems involved in distinguishing one's own actions from others’ (Farrer et al., 2003), the development of the ability to differentiate one's own thoughts and feelings from others’ (Astington et al., 1988), and the social psychological processes in attributing traits and causes to the self vs others (Nisbett et al., 1973; Storms, 1973). Relevant to understanding the temporally extended dimension of the self, research has investigated the neural and cognitive systems that allow for mental time travel into the past and future (Wheeler et al., 1997), the cognitive organization of autobiographical memory (Conway, 2005) and the social psychological causes and consequences of judgments about past and future selves (Conway and Ross, 1984; Liberman and Trope, 1998).