What your eyes give away before your memory does.

The signal hidden in a glance

Memory is the symptom families notice first, but it is rarely the first thing to change. The brain circuits that aim, hold and redirect our gaze run through regions that neurodegeneration touches early, so how a person looks at a moving target can carry information long before they forget a conversation. The problem is that these shifts are too small and too fast for the naked eye to judge in a consulting room.

What the eye-movement research shows

A meta-analysis of saccade studies found that people with mild cognitive impairment and Alzheime’s show longer saccade latencies and more antisaccade errors than healthy peers (Opwonya et al., Neuropsychology Review 2022). In Parkinso’s, oculomotor changes such as hypometric saccades and fixation instability are well documented and track with disease. A camera and a structured task can measure these, with no specialist hardware required.

How Deep Medicine uses the signal

Eye tracking is one of five biomarker streams Deep Medicine captures in a single at-home smartphone session. It is designed to contribute to an early risk picture rather than stand alone, since gaze data is most informative read alongside voice, facial, balance and cognitive signals. The aim is to surface change sooner, when there is more a clinician and patient can do about it.