Parkinson disease dementia

Parkinson disease dementia (PDD) is a neurological disorder characterized by the deterioration of intellectual capacity, particularly attention and visual-spatial processing. It is closely related to dementia with Lewy bodies (DLB), with both conditions involving abnormal deposits of alpha-synuclein protein, known as Lewy bodies, in the brain.1

The neuropathology of PDD involves the loss of dopaminergic neurons in the substantia nigra, a brain region crucial for producing dopamine, a neurotransmitter vital for motor control, memory, and cognition. This loss disrupts normal brain signaling, leading to motor symptoms like tremors and rigidity, as well as cognitive decline. PDD is also associated with a reduction in the brain's cholinergic system, which further impacts attention and cognitive functions. While the exact cause of PDD is unknown, age is a significant risk factor.123