Fig. 2
From: Is insulin-like growth factor-1 involved in Parkinson’s disease development?
Basal ganglia dysfunction and physiopathology of Parkinson’s disease. The progressive loss of ascending dopaminergic projections is the key factor in the establishment of Parkinson’s disease. Continuous lines represent the normal function of basal ganglia; dotted lines represent the normal function of brain segments without the previous inhibition/activation pathway; and red arrows represent the alterations in basal ganglia observed in PD