The purpose of the research is to better understand the motor behavior of individuals in health and disease. The specific purpose of this project is to identify if we can utilize a smartphone to diagnose different movement disorders and monitor their symptoms.

A. Objectives

1. Estimate symptom severity of Essential tremor (ET), Parkinson's disease (PD), Huntington's disease (HD), Primary focal dystonia (PFD), spinocerebellar ataxia (SCA), and Functional movement disorders (FMD) using a smartphone-based application
2. Differentiate individuals with the different movement disorders from healthy controls based on features from the smartphone data
3. Differentiate individuals with a specific movement disorder from people with other movement disorders based on features from the smartphone data

B. Hypotheses / Research Question(s) We hypothesize that we can estimate the severity of symptoms using a smartphone application and that, using those estimates, we can differentiate individuals with movement disorders from healthy controls and from people with other movement disorders.

Movement disorders are a group of neurological conditions that alter human movements. They lead to functional impairments, diminished quality of life, and significant societal, economic, and familial burden. Due to the increase in population and longer life expectancy [1], more and more people will have to live with movement disorders. However, access to movement disorder specialists is already limited and will get worse [2]. Therefore, there is an urgent need to develop tools to aid non-specialist medical professionals identify and manage the symptoms (both motor and non-motor) of those disorders such that specialist can focus on more severe and complex cases. While there are several conditions that can be classified as movement disorders, the current proposal will focus on six disorders that have overlapping symptoms and could prove difficult to differentiate for non-specialists and/or clinicians that do not readily have access to genetic testing or imaging facilities: Essential tremor (ET), Parkinson's disease (PD), Huntington's disease (HD), primary focal dystonia (PFD), spinocerebellar ataxia (SCA), and functional movement disorders (FMD). While trained movement disorder specialists may correctly identify each of these disorders and provide optimal treatment, general practitioners and clinicians living in rural areas that do not have access to the most up-to-date diagnostic tools, such as neuroimaging and genetic testing, may face difficulty when treating those patients due to symptom variability and overlap in symptom presentation between different disorders; leading to sub-optimal treatment outcomes. As such, the development of simple, accurate, and inexpensive tools to help guide their clinical decisions is warranted. The ubiquity of mobile technology and wearable sensors may enable the development of such a tool. In recent years, our group and others have used mobile phones and wearable technology to assess symptoms in a multitude of disorders. This highlights the feasibility of our proposed system for the assessment and monitoring of symptom severity in individuals with movement disorders.

Inclusion Criteria:

• Male and female
• At least 18 years of age
• Ambulatory
• English speaking
• Specific to group 1: a) Diagnosis of ET, b) stable dose of medication for 30 days
• Specific to group 3: a) Diagnosis of PD, b) stable dose of medication for 30 days
• Specific to group 4: a) Diagnosis of HD, b) stable dose of medication for 30 days
• Specific to group 5: a) Diagnosis of PFD, b) stable dose of medication for 30 days
• Specific to group 6: a) Diagnosis of SCA, b) stable dose of medication for 30 days
• Specific to group 7: a) Diagnosis of FMD, b) stable dose of medication for 30 days

Exclusion Criteria:

• Serious untreated psychiatric illness that could impact the data collection
• Inability to understand task or protocol due to cognitive problems
• Other neurological condition that could affect the performance of motor tasks
• Musculoskeletal condition that could affect the performance of motor tasks
• Uncorrected vision impairment
• Specific to groups 1, 3, 4, 5, 6, and 7: Expected change in medication within the next 8 weeks

- People with movement Disorders,

We will recruit 7 parallel groups: 1) ET patients; 2) Healthy controls; 3) PD patients; 4) HD patients; 5) PFD patients; 6) SCA patients; and 7) FMD patients

- Healthy Controls.