Dysfunction of the Default Mode Network in Parkinson Disease

Abstract
Patients with Parkinson disease (PD) demonstrate deficits in executive tasks that include planning and set shifting.1,2 However, the underlying disease-related mechanism is not completely understood. Using functional imaging, neuronal substrates of those deficits were mainly found in the frontostriatal circuitry. Depending on the involvement of the dorsal caudate nucleus (NC), both hypoactivity and hyperactivity of prefrontal areas have been reported in unmedicated patients with PD when compared with controls.3-5