Animal models are established using the laboratory animals to model the human diseases. Examples of diseases that can be induced in laboratory animals include, Parkinson’s disease, Alzheimer’s disease, schizophrenia, attention deficit hyper activity disease (ADHD), and stroke.
However, due to the physiological differences in animals and humans, it is difficult to determine the occurrence of exact symptoms in animals similar to the humans do.
Thus, the blank can be filled with determining whether the symptoms in the animals models and humans are similar.