Overall, K. L., Dyer, D. 2005. Enrichment strategies for laboratory animals form the viewpoint of clinical veterinary behavioral medicine: Emphasis on cats and dogs. ILAR Journal 46(2), 202-216.

Understanding the range of behaviors, behavioral choices, and cognitive stimulation that cats and dogs exhibit under non-laboratory conditions can increase the ability of investigators to predict which enrichments are likely to be the most successful in the laboratory. Many of the enrichment strategies described are surprisingly straightforward and inexpensive to implement.