PITTSBURGH — On a cold, wet afternoon not long ago, Aron Reznick sat in the lounge of a home for the elderly here, his silver hair neatly combed, his memory a fog. He could not remember Thanksgiving dinner with his family, though when he was given a hint — “turkey” — it came back to him, vaguely, like a shadow in the moonlight.

Two years ago, Mr. Reznick, who has early-stage Alzheimer’s disease and is now 82, signed up for an experiment intended to help people with Alzheimer’s and other memory disorders. The concept was simple: using digital pictures and audio to archive an experience like a weekend visit from the grandchildren, creating a summary of the resulting content by picking crucial images, and reviewing them periodically to awaken and strengthen the memory of the event.

The hardware is a little black box called the SenseCam, which contains a digital camera and an accelerometer to measure movement. Worn like a pendant around the neck, it was developed at Microsoft’s research lab in Cambridge, England.

Vicon, a British company that has licensed the technology, is selling its version of the SenseCam only to researchers. For the elderly, though, it could herald a new kind of relationship between mind and machine: even as plaque gets deposited on the brain, everyday experience is deposited on silicon, then retrieved.