Cognitive Dysfunction in Genetic Mouse Models of Parkinsonism

Parkinson’s disease (PD) is primarily recognized as a motor disorder; however, patients also present with a wide range of nonmotor manifestations. Cognitive dysfunctions in nondemented PD patients can occur early in the disease and primarily consist of deficits in executive function. Because it can be assessed with noninvasive measurement tools, cognitive dysfunction could be evaluated to determine the effects of potential disease-modifying agents in patients. A challenge is to reproduce these deficits in animals for preclinical drug testing. Genetic mouse models of PD have been generated based on mutations causing rare familial forms of PD. Although only a few models show extensive nigrostriatal dopamine cell loss, several present extensive anomalies in functions that are also altered in premanifest phases of PD. Here we review the few studies that have so far investigated cognitive function in these new models.