Human mismatch negativity (MMN) is modelled in rodents and other non-human species to examine its underlying neurological mechanisms, primarily described in terms of deviance-detection and adaptation. Using the mouse model, we aim to elucidate subtle dependencies between the mismatch response (MMR) and different physical properties of sound. Epidural field potentials were recorded from urethane-anaesthetised and conscious mice during oddball and many-standards control paradigms; with stimuli varying in duration, frequency, intensity, and interstimulus interval. Resulting auditory evoked potentials, classical MMR (oddball − standard), and controlled MMR (oddball − control) waveforms were analysed. Stimulus duration correlated with stimulus-off response peak latency (p < 0.0001). Frequency (p < 0.0001), intensity (p < 0.0001), and inter-stimulus interval (p < 0.0001) correlated with stimulus-on N 1 and P 1 (conscious only) peak amplitudes. These relationships were instrumental in shaping classical MMR morphology in both anaesthetised and conscious animals, suggesting these waveforms reflect modification of normal auditory processing by different physical properties of stimuli. Controlled MMR waveforms appeared to exhibit habituation to auditory stimulation over time, which was equally observed in response to oddball and standard stimuli. These observations are inconsistent with the mechanisms thought to underlie human MMN, which currently do not address differences due to specific physical features of auditory deviance. Thus, no evidence was found to objectively support the deviance-detection or adaptation hypotheses of MMN in relation to anaesthetised or conscious mice.Mismatch negativity (MMN) is widely believed to reflect pre-attentive sensory-2 memory. It is observed in response to an oddball paradigm, in which many identical 3 standard stimuli are infrequently replaced with deviant oddball stimuli. This study 4 concerns the auditory modality, as does the majority of literature on MMN. Odd-5 ball stimuli may deviate from the standard in any discriminable feature of sound 6 (Pakarinen et al., 2007). The auditory-evoked potential (AEP) from the standard is 7 conventionally subtracted from that of the oddball, generating a difference wave-8 form that constitutes the MMN. This may be referred to as the classical approach. 9 Interestingly, MMN is observed from patients in anaesthetised and comatose states 10 (Fischer et al., 1999(Fischer et al., , 2000Kane et al., 1996), suggesting that the mechanisms re-11 sponsible for its generation are not reliant on consciousness. The prevailing theory 12 is that a mismatch between novel auditory input and a memory-representation, or 13 predictive model, of recently experienced auditory inputs, triggers updating of this 14 model, thereby subconsciously capturing the attention. This manifests in scalp-15 recorded EEG as a MMN component (Winkler et al., 1996). This interpretation has 16 remained largely unchanged since its rationale was first proposed (Näätänen et al., 17...