Transcranial Photobiomodulation as a Therapy for Patients With Parkinson's Disease: Relationship Between Pain and Brain Functional Connectivity (FBM)

1. Objectives General: Evaluate the effects of applying transcranial photobiomodulation in patients with Parkinson's disease who show increased pain intensity when off levodopa. Specific: - Evaluate pain intensity using the Visual Analog Scale (VAS) before and after transcranial photobiomodulation sessions; - Evaluate the sensitive, discriminative, affective-motivational and cognitive dimensions of pain by applying the McGill questionnaire before and after the end of treatment; - Identify and grade pain by applying the King's Parkinson's Disease Pain Scale (KPPS) before and after treatment; - Evaluate cognitive motor behavior using the Timed Up Go (TUG) and TUG Dual Task test at the beginning and end of treatment; - Analysis of brain connectivities related to pain (connectivities of the thalamus, right cingulate cortex, striatum (caudate nucleus and putamen), and substantia nigra) using Functional Magnetic Resonance Imaging at rest before and after the end of treatment