Modification of Threat Interpretation Bias to Reduce Anxiety in Neurodegenerative Movement Disorders (Aim 3)

This study is testing a mobile app-based program that helps people with Huntington's disease or Parkinson's disease manage anxiety. The app works by training people to interpret uncertain situations in a less threatening way. **You may be eligible if...** - You have a clinical (or genetic) diagnosis of Huntington's disease or Parkinson's disease - You are experiencing anxiety symptoms (measured by a standard questionnaire) - You are 21 years old or older - You live in the USA - You can read and understand English - You have regular access to a smartphone or tablet that can download the app **You may NOT be eligible if...** - You have significant cognitive decline that would prevent you from completing the program - You have active suicidal thoughts - You do not have a compatible internet-connected device Talk to your doctor to see if this trial is right for you.