Prediction of Amyloid and Mild Cognitive Impairment in Early Stage Alzheimer's Disease From Remote Speech Phenotyping

Inclusion Criteria: * Amyloid status must be known, based on an amyloid PET scan or CSF amyloid test, no older than 30 months at the time of consent for Arm 2 and Arm 4 participants (amyloid negative Arms). * Amyloid status must be known, based on an amyloid PET scan or CSF amyloid test, no older than 60 months at the time of consent for Arm 1 and Arm 3 (amyloid positive Arms). * Subjects must be aged 50-85 (inclusive). * Subjects must have MMSE scores of 23-30 (inclusive) based on a test not older than 1 month at the time of the visit. * Date of diagnosis (if applicable) maximum of five years prior to consent. * Subjects' first language must be English. * Willing to participate in a study investigating speech and cognitive impairment. * Able to provide valid informed consent. * Able to use, or has a caregiver who is able to use a smartphone device. * Has access to a smartphone device running an operation system of Android 6 or above; or iOS 10 or above. If taking part in the study through virtual visits, the following inclusion criteria also applies: * Able to use, or has a caregiver who is able to use a personal computer, notebook or tablet. * Has access to a personal computing device of that is running an operating system of macOS X with macOS 10.9 or later, or Windows 7 or above, or Ubuntu 12.04 or higher; OR has access internet browser software Internet Explorer version 11 or above; or Microsoft Edge version 12 or above, or Firefox version 27 or above, or Google Chrome version 30 or above, or Safari version 7 or above; AND capable of audio and video recording; AND able to connect to the internet. Exclusion Criteria: * Clinically significant unstable psychiatric illness in 6 months. * Diagnosis of General Anxiety Disorder. * Current, or history within the past 2 years of major depressive disorder diagnosis (according to DSM-5 criteria83); or psychiatric symptoms that, in the opinion of the investigator, could interfere with study procedures. * History or presence of stroke within the past 2 years. * Documented history of transient ischemic attack or unexplained loss of consciousness within the last 12 months. * The participant is using drugs to treat symptoms related to AD, and the doses of these drugs were not stable for at least 8 weeks prior to consent. * Participant is, or previously has been enrolled in the Sponsor's NOV-0100 or NOV-0110 studies.