Quantitation of naturalistic behaviors

Naturalistic behaviors are behaviors that organisms exhibit 'in nature'. Eating, sleeping and sexual behaviors are examples. Since naturalistic behaviors are observed to occur without any apparent training or learning, some people mistakenly believe that all naturalistic behaviors are unlearned, and are thus different from laboratory behaviors. We maintain that naturalistic behaviors can be studied profitably in the toxicological laboratory, using quantitative techniques from behavioral neuroscience. Understanding of toxicity and underlying mechanisms is enhanced when naturalistic behaviors are thought of as responses to stimuli. Stimuli that influence naturalistic behaviors may arise inside the organisms (e.g., physiological signals of hunger) or outside the organisms (e.g., the smell of food or the start of the nocturnal lighting cycle). A practical, noninvasive, automated system can be used to improve upon the cage-side observation currently used to evaluate naturalistic behaviors in toxicity screening. Effects of alkyltins and other neurotoxicants upon eating, drinking, rearing, and the daily cycle of rest-activity will be shown. The rodent's pattern of nocturnal activity has proven to be particularly sensitive to neurotoxicants, and thus deserves additional attention in developing neurobehavioral toxicology.