In spite of extensive research into its antecedents, considerable disagreement remains about the neurophysiology underlying the P600. Upon its discovery (Osterhout & Holcomb, 1992; see also Hagoort, Brown, & Groothusen, 1993), the P600 was seen as a new, distinct component reflecting aspects of combinatorial processing, e.g. the resolution of syntactic errors. Today, many researchers consider the P600 a specific component reflecting interpretative/integrative brain processes (e.g. Brouwer et al., 2012, Friederici, 2011, Gouvea et al., 2010, Kaan, 2007 and Osterhout and Hagoort, 1999). Others (e.g. Bornkessel-Schlesewsky et al., 2011, Coulson

et al., 1998a, Münte et al., 1998, van de Meerendonk et al., 2010 and Vissers et al., 2008) view the P600 as a P3b, an instance Onalespib mouse of the well-known P3 component family. Here, we approach the P600/P3 discussion from a novel perspective. By applying single-trial ERP analyses to a P600-eliciting paradigm, we aimed to test whether the P600 shows a well-established property of the P3:

latency alignment with reaction times. We argue that, if the response properties between the P600 and P3 are similar in this respect, this strengthens the view that we can draw upon the wealth of existing knowledge about the psychological and neural properties of the P3 to inform a detailed, neurobiologically grounded view of the P600. Like the P600, the P3 check details is a broad positive wave, often with a centro-parietal maximum. It is elicited anywhere from 250 to 1000+ ms after motivationally significant events. The best-known paradigm for eliciting P3 effects is the oddball paradigm, in which participants engage in a task involving infrequent target stimuli amongst frequent standard stimuli (i.e. targets are responded to, counted etc.). Accordingly, the P3 is often described as a component that is elicited by uncertain, unexpected or surprising stimuli (e.g. Donchin, 1981 and Sutton et al., 1965). However, while unexpectedness constitutes a very effective way of rendering a stimulus

subjectively significant, it is neither a sufficient nor a necessary precondition. For example, task-relevant stimuli (i.e. stimuli which require a response) engender a higher P3 amplitude than stimuli Vasopressin Receptor which do not, even when stimulus frequency is equated between the two stimulus categories (Duncan-Johnson & Donchin, 1977). A P3 also follows significant or intrusive stimuli in fully task-free paradigms, e.g. to one‘s own name even while asleep or comatose (Perrin et al., 1999 and Perrin et al., 2006), and non-task relevant stimuli of personal significance during standard psychological tasks, like one’s own cellphone ringtone (Roye, Jacobsen, & Schröger, 2007) or name (Gray, Ambady, Lowenthal, & Deldin, 2004) as a distractor item.