The parameterization method used in this work extracts the aperiodic components of the power spectrum, which are suggested to be related to the neuronal activity of the surrounding brain area, as well as refines the interpretation of power changes in the power spectrum of both narrowband and broadband frequencies. It considers the power spectrum as a summation of periodic and aperiodic components. Literature findings suggest that the aperiodic components are related to the balance of excitatory and inhibitory postsynaptic currents (exponential), the neuronal time scale (knee frequency), and the firing rate (offset) of neurons near the recorded region. On the other hand, the periodic components have the same interpretation as usual and are related to the synchronization of neuronal assemblies. 

Thus, the work aims to investigate whether the aperiodic components are statistically different when compared across different phenotypic groups and different conditions of rest and movement, as well as whether any of the aperiodic components correlate with any of the canonical Parkinson's motor symptoms of rigidity, bradykinesia, and tremor. Moreover, how the statistical findings support the current literature on the basal ganglia model for PD and movement considering different Parkinson's phenotypes, and possible new lines of investigation to enhance our understanding of the physiological mechanisms of this disease.