The Science
Thirty years of memory research, in three minutes.
MemTrax is a continuous-recognition task: you watch a stream of images and respond when one repeats. It sounds simple because it is — but the pattern of what you recognize, what you miss, and how fast you respond is one of the most sensitive available windows into episodic memory, the system Alzheimer's disease attacks first.
What the test actually measures.
Recognition, not recall
Asking someone to remember a word list tests retrieval, effort, and language all at once. Recognition isolates the memory trace itself — did this image leave a mark, or didn't it.
Four signals, not one score
Every response is a hit, a correct rejection, a miss, or a false positive. That structure comes from signal detection theory, and it separates genuine memory strength from guessing and response bias.
Speed as a second channel
Reaction time on correct responses carries information that accuracy alone misses. Slowing often shows up before errors do.
Built to be repeated
A single score is a data point. The same validated task taken over years is a trajectory — and change over time is what distinguishes ordinary forgetfulness from something progressive.
Who invented MemTrax.
Dr. J. Wesson Ashford is a psychiatrist and neuroscientist who has spent his career on a single question: how does Alzheimer's disease take memory apart, and how do you measure it early enough to matter.
He is Chair of the Memory Screening Advisory Board of the Alzheimer's Foundation of America and a Senior Editor of the Journal of Alzheimer's Disease. He directs the War-Related Illness and Injury Study Center at the VA Palo Alto Health Care System and is a Clinical Professor (affiliated) of Psychiatry and Behavioral Sciences at Stanford University, where he continues as a Senior Research Scientist at the Stanford/VA Aging Clinical Research Center.
He earned both an M.D. and a Ph.D. at UCLA. His dissertation on massive parallel information processing in the cerebral cortex was a finalist for the Lindsley Prize in Behavioral Neuroscience in 1984, and he was the first to propose the leading theories on how Alzheimer's disease disrupts neuroplasticity and basic memory mechanisms.
A research record that built the field.
-
1978
The first anti-cholinesterase trial
Dr. Ashford ran the first double-blind trial of an anti-cholinesterase drug — physostigmine — for dementia. Four drugs in that class are now FDA-approved for Alzheimer's disease.
-
1989
Modern Test Theory meets medicine
The first application of Item Response Theory to clinical medicine, showing how individual test items deteriorate in sequence over the course of Alzheimer's disease. That principle underlies every modern dementia assessment.
-
1990s
The ten-year window
Work in the mid-1990s established that the memory impairment of early Alzheimer's disease can be projected to begin at least a decade before dementia can be clinically diagnosed — the finding that makes early screening worth doing at all.
-
1998
How the disease destroys memory
A histopathology study demonstrating for the first time the mechanism by which Alzheimer's disease destroys memory, alongside brain imaging work and the development of a Time-Index method for tracking dementia progression precisely.
Why MemTrax exists.
The work began in the 1980s out of a recognition that the field had no adequate way to evaluate memory loss in dementia. If impairment starts ten years before diagnosis, then the ability to screen people during that window is the difference between managing a disease and watching it arrive. MemTrax was built to make that screening simple enough that people would actually do it — and quantifiable enough that repeating it means something.
The published evidence.
MemTrax has been validated across peer-reviewed studies, conference research, and one of the largest normative cognitive datasets ever assembled.
-
Large-scale validation study
An extensive study of more than 1,000 participants showing that MemTrax performance is associated with age and can reveal indications of mild cognitive impairment, dementia, or Alzheimer's disease.
-
Age association findings
Presented findings on the relationship between MemTrax performance and age-related cognitive change.
-
Reliability analysis
Rigorous testing of test–retest reliability, the property that makes longitudinal tracking meaningful.
-
Accuracy analysis
Analysis of MemTrax measurement accuracy against established assessment standards.
Studies in progress
The MEDIAG Early Diagnosis of Memory Disorders Study and the MemTrax Cognitive Assessment Reliability Study are ongoing, gathering further evidence for the use of continuous-recognition screening in early detection — particularly for the indicators of early dementia that increase with age.
Measure your memory.
Three minutes. No preparation. Take it once for a baseline, then again whenever you want to know if anything has changed.
MemTrax is a screening and self-monitoring tool. It is not a diagnostic instrument and does not replace evaluation by a qualified clinician. If you have concerns about your memory, speak with your doctor.