[Vocalization response used for evaluation of pain-related behavior in guinea pigs]

In general, pain has been defined as "an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage", and hence pain is a subjective and emotional experience for each individual. For this reason, it is difficult to study pain in nonverbal animals. However, painful stimuli (noxious stimuli) can cause both a simple and an overt emotional behavior such as self-defense reaction and vocalization in animals. Therefore, we are able to measure these behaviors as nonverbal communication of pain. The vocalization responses is the natural nociceptive reaction of conscious animals and prelingual children. In the present overview, we described the methodology for objective assessment of guinea pig's vocalization response to arterial algogenics and its characteristics.