Audio and Vision-Based Evaluation of Parkinson’s Disease from Discourse Video Francis Quek, Robert Bryll, Mary Harper, Lei Chen, Lorraine Ramig Vision Interfaces & Sys. Lab. Purdue University University of Colorado, Boulder CSE Dept., Wright State U. West Lafayette, IN Boulder, CO Dayton, OH Correspondence: quek@cs.wright.edu Abstract Parkinson’s disease (PD) belongs to a class of neurodegen- erative diseases that affect both the patient’s speech and motor capabilities. To date, PD diagnosis and the determi- nation of disease progress and treatment efficacy is based entirely on the subjective observation of a trained physi- cian. We present the results of a pilot study of two Id- iopathic PD patients who have undergone Lee Silverman Voice Treatment (LSVT). It has been observed subjectively that gestural performance of patients improve in tandem with speech improvements after LSVT. It is hypothesized that these improvements are taking place at a neurologi- cal level. Measurements of speech and gesture suggest that LSVT improves the quality of both gesticulation and speech. 1 Introduction Parkinson’s disease (PD) belongs to a class of neurodegen- erative diseases that affect both the patient’s speech and motor capabilities. Currently there are one and a half mil- lion sufferers of the disease and this number is expected to rise fourfold by 2040 [1]. Parkinson’s Disease (PD) is a progressive neurodegenerative disorder in which death of dopaminergic cells in the substantia nigra results in a vari- ety of changes in motoric function such as delay in initiation of movement, increase in resting muscle tone, slowness of movement, and resting tremor [2, 3]. Cognitive changes, such as slowed information processing (bradyphrenia) [4], and loss of postural reflexes may also occur [5]. Speech changes are common; approximately 70% of Parkinson’s patients have speech problems. Parkinson’s patients of- ten exhibit monotonous pitch and loudness, reduced stress, variable speech rate, short rushes of speech, and impre- cise consonant articulation. They also manifest hypopho- nia, start-hesitation or stuttering, or delay in the produc- tion of speech, which is often difficult to distinguish from bradyphrenia [6, 7]. There are currently no widely available tests for PD. Di- agnosis and assessment of progression of the disease are done on the basis of serial clinical examinations, relying on the subjective evaluation of a trained physician, often using the modified Hoehn and Yahr staging and the United PD Rating Scale (UPDRS) [8, 2]. In this paper, we present research in which we analyzed the before and after treatment videos of two PD patients who underwent a treatment program known as Lee Silver- man Voice Treatment (LSVT) [9]. This treatment applies voice therapy methods to improve the speech intelligibil- ity of PD patients. Subjective observations indicate that not only did speech qualitatively improve, the accompanying gesticulation appeared to improve as well. We present a set of metrics that we employed to detect this subjective obser- vation. 2 Background The reduced ability to communicate is considered to be one of the most difficult aspects of Idiopathic Parkinson’s Dis- ease (IPD) by many IPD sufferers and their families. Soft voice, monotone, breathiness, hoarse voice quality, and im- precise articulation, together with lessened (masked) facial expression, contribute to limitations in communication in the vast majority of individuals with IPD [10, 11]. The initial treatment aim of LSVT is to improve the phonatory source in individuals with IPD. The treatment typically results in significant, long-term improvement in laryngeal valving and post-treatment changes in thyroary- tenoid muscle activity, subglottal air pressure, maximum flow declination rate, voice sound pressure level (SPL), loudness and voice quality [12, 13, 14]. LSVT uses phonation as a trigger to increase effort and coordination across the speech production system through stimulating the global variable “loud.” Speech production is a learned, highly practiced motor behavior, with many of its movements regulated in a quasiautomatic fashion [15, 16]; loudness scaling is a task that humans engage in all their lives [17, 18]. For example, it is common to increase loud- ness to improve speech intelligibility when speaking against noise or when the listener is far away. By targeting loud- 1 Authorized licensed use limited to: Johns Hopkins University. Downloaded on March 19, 2009 at 21:10 from IEEE Xplore. Restrictions apply.