More than a rhythm of life: breathing as a binder of orofacial sensation.

When rodents engage in the exploration of novel stimuli, breathing occurs at an accelerated rate that is synchronous with whisking. We review the recently observed relationships between breathing and the sensations of smell and vibrissa-based touch. We consider the hypothesis that the breathing rhythm serves not only as a motor drive signal, but also as a common clock that binds these two senses into a common percept. This possibility may be extended to include taste through the coordination of licking with breathing. Here we evaluate the status of experimental evidence that pertains to this hypothesis.