Computerized Tests of Cognitive Decline in Presymptomatic Alzheimer's Disease

Study Overview
=================
Brief Summary
-----------------
The investigators will study performance on computerized cognitive tasks in healthy participants of different ages to gather normative data for newly developed computerized cognitive tests. These tests are designed to permit the early detection of individuals at risk of age-related cognitive decline.

Detailed Description
-----------------
In Group A, the investigators will evaluate the performance of healthy older participants (N = 300, age range 60 to 89 years) for three days at enrollment and then at 6-month intervals for three years thereafter. The goal is to characterize changes in performance to aging and task experience in a group of older subjects. In Group B, the investigators will compare the performance of normal participants (N = 100, age range 18 to 89) on computerized and manually administered cognitive tasks. In Group C, the investigators will gather normative data from participants across the age range (N = 100, ages 18 to 89) for three days at enrollment, to better characterize test-retest reliability scores on Day 1 tasks. In Group D, the investigators will evaluate the performance of healthy older participants (N = 1200, age range 60 to 89 years) for three days at enrollment and then at 6-month intervals for three years thereafter. In the aim of better understanding health disparities in cognitive testing, this group will be divided into four cohorts: 300 African American participants; 300 Asian American participants; 300 Latino English-speaking participants; and 300 Latino Spanish-speaking participants, who will complete a Spanish translation of our computerized cognitive tests.

Official Title
-----------------
Computerized Tests of Cognitive Decline in Presymptomatic Alzheimer's Disease

Conditions
-----------------
Alzheimer Disease, Cognitive Decline, Aging

Intervention / Treatment
-----------------
* Diagnostic Test: California Cognitive Assessment Battery


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Must be able to use computer mouse and touch screen Must speak English as a primary language Must speak Spanish as a primary language (for Latino participants completing our Spanish translation) Exclusion Criteria: History of psychiatric disorder History of stroke or transient ischemic attack History of substance abuse History of medical or sensory disorders that are incompatible with effective testing History of traumatic brain injury with hospitalization and extended loss of consciousness History of epilepsy History of depression or anxiety

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 89 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Diagnostic
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Older participant group<br>We will evaluate the performance of healthy older participants (N = 300, age range 60 to 89 years) for three days at enrollment and then at 6-month intervals for three years thereafter. The goal is to characterize changes in performance to aging and task experience in a group of older subjects. | Diagnostic Test: California Cognitive Assessment Battery<br>* The California Cognitive Assessment Battery (CCAB) is a collection of computerized cognitive tests that will be telemedically administered to participants in their homes using a tablet computer and accessories provided by the research team. Testing may also occur in research laboratories. Previous versions of CCAB tests have been described in 16 manuscripts which describe (a) the psychometric characteristics of normative data collected in large participant populations (300 to 2,300 subjects for different tests) and (b) the sensitivity of CCAB tests for detecting performance abnormalities in patients with traumatic brain injury (TBI) and in control participants simulating the cognitive deficits that follow mild TBI.<br>* Other names: CCAB;|
| Experimental: CCAB vs. manual test group<br>We will compare the performance of normal participants (N = 100, age range 18 to 89) on computerized and manually administered cognitive tasks. | Diagnostic Test: California Cognitive Assessment Battery<br>* The California Cognitive Assessment Battery (CCAB) is a collection of computerized cognitive tests that will be telemedically administered to participants in their homes using a tablet computer and accessories provided by the research team. Testing may also occur in research laboratories. Previous versions of CCAB tests have been described in 16 manuscripts which describe (a) the psychometric characteristics of normative data collected in large participant populations (300 to 2,300 subjects for different tests) and (b) the sensitivity of CCAB tests for detecting performance abnormalities in patients with traumatic brain injury (TBI) and in control participants simulating the cognitive deficits that follow mild TBI.<br>* Other names: CCAB;|
| Experimental: Test-Retest Reliability group<br>We will gather normative data from participants across the age range (N = 100, ages 18 to 89) for three days at enrollment, to better characterize test-retest reliability scores on Day 1 tasks. | Diagnostic Test: California Cognitive Assessment Battery<br>* The California Cognitive Assessment Battery (CCAB) is a collection of computerized cognitive tests that will be telemedically administered to participants in their homes using a tablet computer and accessories provided by the research team. Testing may also occur in research laboratories. Previous versions of CCAB tests have been described in 16 manuscripts which describe (a) the psychometric characteristics of normative data collected in large participant populations (300 to 2,300 subjects for different tests) and (b) the sensitivity of CCAB tests for detecting performance abnormalities in patients with traumatic brain injury (TBI) and in control participants simulating the cognitive deficits that follow mild TBI.<br>* Other names: CCAB;|
| Experimental: Health Disparities group<br>We will evaluate the performance of healthy older participants (N = 1200, age range 50 to 89 years) for three days at enrollment and then at 6-month intervals for three years thereafter. In the aim of better understanding health disparities in cognitive testing, this group will be divided into four cohorts: 300 African American participants; 300 Asian American participants; 300 Latino English-speaking participants; and 300 Latino Spanish-speaking participants, who will complete a Spanish translation of our computerized cognitive tests. | Diagnostic Test: California Cognitive Assessment Battery<br>* The California Cognitive Assessment Battery (CCAB) is a collection of computerized cognitive tests that will be telemedically administered to participants in their homes using a tablet computer and accessories provided by the research team. Testing may also occur in research laboratories. Previous versions of CCAB tests have been described in 16 manuscripts which describe (a) the psychometric characteristics of normative data collected in large participant populations (300 to 2,300 subjects for different tests) and (b) the sensitivity of CCAB tests for detecting performance abnormalities in patients with traumatic brain injury (TBI) and in control participants simulating the cognitive deficits that follow mild TBI.<br>* Other names: CCAB;|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Longitudinal normative data collection from healthy participants | Multiple behavioral outcome measures will be obtained from each cognitive test including measures of response time (in milliseconds) and accuracy (in percent correct). Recordings of subject's verbal responses will also be analyzed phonologically and automatically transcribed to permit the lexical, syntactic, and semantic analysis of speech output. Questionnaire data will be used to identify factors that may influence performance on the cognitive tests. The primary outcome measures are the scores obtained during enrollment testing that predict a decline in longitudinal performance. | Longitudinal testing at six-month intervals | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Aging, Elderly, Alzheimer's disease, Cognition, Computerized, Testing