Establishing appropriate animal models is critical for studying schizophrenia. Based on the Processing-Protection Theory, schizophrenia is mainly caused by deficits in gating of signal processing. Prepulse inhibition (PPI) is the reduction of the startle reflex when the startling stimulus is shortly preceded by a non-startling stimulus, and has been used as a model for studying sensorimotor gating. In humans, PPI can be enhanced by both attention and emotion. Our recent studies have shown that PPI in rats c...