Not all cross-modal responses are explained by face movements.

Recent work has claimed that most apparently cross-modal responses in sensory cortex are instead caused by the face movements evoked by stimuli of the non-dominant modality. We show that visual stimuli rarely trigger face movements in awake mice; when they occur, such movements do not explain visual responses in auditory cortex; and in simultaneous recordings, face movements drove artifactual cross-modal responses in visual but not auditory cortex. Thus face movements do not broadly explain cross-modal activity across all stimulus modalities.