Figure 3.

Parkinson’s disease: a continuum or distinct events hypothesis? The condition is characterized by the presence of (1) predisposing genetic, environmental, and lifestyle factors that together contribute to both (2) systemic and neuro-inflammation. (3) Autonomic dysfunction and a (4) dysregulated bidirectional signalling system and (5) α-Syn aggregation are associated with (6) motor and dopaminergic neuron dysfunction. We argue that there is a positive feedback mechanism between (5) α-Syn aggregation and (3) autonomic dysfunction.