The Role of EEG in Identifying Cognitive Changes in Parkinson's Disease

Overview

This study is a group controlled clinical trial. Parallel study, patients aged 40-80 years, with Parkinson disease. Twelve sessions, three times a week, for 30 minutes. Training will consist of Transcranial Direct Current Stimulation linked to tredmill training, in 3 blocks of 7 minutes, and adicionally to the Experimental Group, dual-task cognitive-motor exercises, simultaneously. The investigators will use the folowwing instruments: Auditory Stroop Test, Trail Making Test, Montreal Cognitive Assessment, Timed-up-and-go ST and DT, UPDRS II and III and Eletroencefalography (EEG). The objective is to examine cognitive alterations on PD pacients due to intervention and the relationships between baseline outcomes in responders and non-responders to therapy.

Background: Parkinson disease (PD) is one of the most common age-related brain disorders. PD is defined primarily as a movement disorder, with the typical symptoms being resting tremor, rigidity, bradykinesia and postural instability. In addition to the defining dopamine-related motor symptoms, however, PD is increasingly recognized as a heterogeneous multisystem disorder involving other neurotransmitter systems, such as the serotonergic, noradrenergic and cholinergic circuits. Thus, a wide variety of nonmotor symptoms (NMS) linked with these neurotransmitters are commonly observed in patients with PD. Cognitive decline is among the most common and important NMS. Robust evidence indicates that in comparison with age-matched groups without PD, people with PD exhibit more rapid decline in a number of cognitive domains - in particular, executive, attentional and visuospatial domains, but also memory. In recent years, research has focused on the pre-dementia stages of cognitive impairment in PD, including mild cognitive impairment (MCI). Several longitudinal studies have shown that MCI is a harbinger of dementia in PD, although the course is variable, and stabilization of cognition - or even reversal to normal cognition - is not uncommon. A variety of biomarkers have been studied, some using novel structural and functional imaging techniques, and have documented in vivo brain changes associated with cognitive impairment. Patients with Parkinson's disease have difficulty performing a dual-task, a condition present in everyday life. It is possible that strategies such as Transcranial Direct Current Stimulation can be associated with motor training enriched with dual-task and cognitive training to improve the performance of two concurrent tasks. It is currently unclear whether specific tasks and clinical conditions of PD patients have different results after the intervention. Therefore, the proposed randomized controlled trial will examine the effects of a intervention protocol on brain eletric activity and cognitive outcomes on PD patientes and the relationships between baseline outcomes in responders and non-responders to therapy. Discussion: This study will evaluate the effectiveness of an intervention protocol with transcranial direct current stimulation, dual-task motor-cognitive training in patients with Parkinson's disease. The study will also highlight whether, by qEEG analysis, the clinical factors and variability between individuals that could interfere in the efficacy intervention and influence the therapeutic effect.