Towards a Speech-Test for Parkinson's Disease Detection: a Diachronic Study on Michael J. Fox

Recent studies have shown that two acoustic parameters - i.e. percentage of vocalic portions (%V) and the average duration of the intervals (VtoV) between two consecutive Vowel Onset Points - increase with aging. Besides, according to the spectroacoustic analysis of five Karol Wojtyla's public speeches produced before and after he discovered to be affected by Parkinson's Disease (PD) the two parameters are connected with the insurgence and the progression of PD. The results of acoustic analysis of read speech in Italian and Polish have confirmed that neurogenetic disorders determine abnormal variation in %V. In the present study the speech of the Canadian actor Michael J. Fox has been analyzed. The results of the analysis show that in 1986, 5 years before the diagnosis of PD, %V undergoes a significant increase. The authors propose a project intended to build a speech-test that would help medical professionals to diagnose PD in advance.