 Neurological disorders such as Parkinson's disease can be studied in animals to better understand the disease process and develop treatments. Animal models have been used to study the effects of various toxins and genetic mutations on the development of Parkinson's symptoms, including tremors, rigidity, slowed movement and loss of muscle control. Additionally, animal models have been developed to study the progression of the disease and test potential therapies. This article was authored by Javier Blaser, Sudarshan Funny, Vanese Jackson-Lewis, and others.