Squirrel monkey behavior in research.

Abstract

Squirrel monkeys have been a valuable animal model in biomedical research (Abee 2000). They have been utilized in a wide variety of study areas including, but not limited to, atherosclerosis, neuroscience, pharmacology, psychiatry, toxicology, and vision research. A quick search of on-line databases MEDLINE and PS YCHINFO indicates that approximately 200 articles have been published in the last 10 yr that have used behavioral testing of squirrel monkeys. Analysis of experimental manipulations of Saimiri behavior has been an important tool. Depending on the level of analysis needed, several different behavioral testing protocols have been used successfully in biomedical research using squirrel monkeys. If a predicted effect is on the whole organism, other than studying the natural behavior of an animal, investigating its interaction with social partners and its environment has been most appropriate. If the effects of interest are more limited, more specific tests of the squirrel monkey's motor performance, cognitive ability, or reflex actions may enable an investigator to isolate the consequence of the experimental intervention. The purpose of this article is to review how behavior has been employed using squirrel monkeys in biomedical research. We describe three general types of behavioral analysis: natural behavior, conditioned behavior, and neurobehavioral assessment profiles. Natural behavior refers to data collected on squirrel monkeys as they move about the environment. This type of analysis includes studies of animals in seminatural and captive laboratory environments as well as field studies. Although an investigator can arrange particular situations in all three study types, a key difference between behavioral analysis and conditioned tests is usually in the investigator's direct supply of rewards or punishments (conditions) in the latter. Conditioned behavior tests (cognitive, classical, and instrumental paradigms) are used to investigate the squirrel monkey's ability to learn or react to environmental stimuli. Classical conditioning entrains reflexive behavior to stimuli that do not normally elicit it. Cognitive and instrumental conditioning relies on animal tendencies to maximize rewards and minimize punishment in an effort to examine its