Psychotic disturbances (PsD) are quite common in PD patients. Well-formed complex visual hallucinations (VHs) represent the most common presentation of PsD, with higher incidence in advanced PD. Auditory, olfactive, and tactile hallucinations may also occur, less frequently. Paranoid delusions, Othello’s syndrome, and other kinds of delusions are other possible presentations of psychosis in PD [128,129]. Several theories have been proposed in order to explain the occurrence of these phenomena in synucleinopathies, mostly in PD and in DLB. Previous hypothesis included visual deafferentation (as in Charles-Bonnet’s syndrome), loss of cortical inhibition, adverse effects to dopamine supplementation, monoaminergic imbalance, and others [130,131]. Nowadays, a complex model has been proposed, involving different neural networks, namely Thalamocortical dysrhythmia (TCD) [132].