Animal Model - Criticisms

Criticisms

Many animal models serving as test subjects in biomedical research, such as rats and mice, may be selectively sedentary, obese and glucose intolerant. This may confound their use to model human metabolic processes and diseases as these can be affected by dietary energy intake and exercise.

Animal models of psychiatric illness give rise to other concerns. Qualitative assessments of behavior are too often subjective. This would lead the investigator to observe what s/he wants to observe in subjects, and to render conclusions in line with his/her expectations. Also, the imprecise diagnostic criteria for psychiatric illnesses inevitably lead to problems modeling the condition; e.g., since a person with major depressive disorder may experience weight loss or weight gain, insomnia or hypersomnia, we cannot with any certainty say that a rat with insomnia and weight loss is depressed. Furthermore, the complex nature of psychiatric conditions makes it difficult/impossible to translate human behaviors and deficits; e.g., language deficit plays a major role in autistic spectrum disorders, but – since rodents do not have language – it is not possible to develop a language-impaired "autistic" mouse.

In addition to the myriad ethical concerns of using animals in biomedical research, animal studies of psychiatric illness raise further concerns about the pain and suffering inflicted on the test subjects. While some scientists argue that care is taken to prevent unnecessary suffering in animal experiments, suffering is an inherent aspect of modeling distressful psychiatric conditions (e.g., anxiety, depression, posttraumatic stress disorder).