Parkinson's Disease: Diagnostic Challenges Amidst Transdiagnostic and Overlapping Mental Health Symptoms.

Parkinson's disease (PD) is a complex neurodegenerative disorder with heterogeneous clinical presentations. Given the ambiguity of its overlapping symptomatology and concomitant atypical motor and neuropsychological symptoms its early diagnosis is clinically challenging. It is often missed since low mood, anhedonia, lack of motivation, and psychomotor retardation are commonly reported in individuals with PD. When alexithymia is the predominant symptom, the knowledge to discriminate between apathy, anhedonia, and alexithymia is critical to avoid misdiagnosis.