Fig. 1.

Representative grand average auditory event related potential recordings from human scalp, mouse surface and mouse depth electrodes. Note that the overall pattern of event related activity is consistent across species and locations, with a prominent P1, N1 and P2 components. These responses are termed “obligatory” as they occur in response to a simple tone or click in rodents, non-human primates or clinical populations. These components occur at 40% of the human latency in mouse. Thus, the P1 occurs at 20 ms in mouse and 50 ms in human, while the N1 and P2 occur at 40 and 80 ms in mouse and 100 and 200 ms in human respectively. Studies over the past decade demonstrate that each component in mouse shares psychometric and pharmacological response properties with the corresponding human ERP component, yielding excellent predictive validity (Amann et al., 2008; Connolly et al., 2004; Ehrlichman et al., 2009; Halene and Siegel, 2008; Maxwell et al., 2004a,b, 2006; Metzger et al., 2007; Phillips et al., 2007; Rudnick et al., 2008; Siegel et al., 2003, 2005).