Vestibular spontaneous response as a potential signature for Parkinson's disease.

In this paper, we report on a new method for potential diagnosis of Parkinson's Disease (PD) based on the analysis of the spontaneous response of vestibular system recorded by Electrovestibulography (EVestG). EVestG data of 20 individuals with PD and 28 healthy controls were adopted from a previous study. The field potentials and their firing pattern in response to whole body tilt stimuli from both left and right ears were extracted. We investigated several statistical and fractal features of the field potentials and also their firing patterns. One-way analysis of variance (ANOVA) was used to select the features showing the most significant differences between individuals with PD and the age-matched controls. Linear Discriminant analysis classification was applied to every selected feature using a leave-one-out routine. The result of each feature's classifier was used in a heuristic weighted average voting system to diagnose PD patients. The weights of the voting system were the (posterior) probabilities calculated by the designed classifier to indicate a subject related to a specific class. The results show more than 97% accuracy for PD diagnosis. Given that the patients were at different stage of disease, the high accuracy of the results encourages the use of vestibular response for PD diagnosis as a plausible quick and non-invasive screening tool.