Your smartphone might be able to remind you to buy a cake for your niece’s fifth birthday. But whether an Alzheimer’s patient will remember watching her blow out the candles is much more hit-or-miss. Morgan Barense, a neuroscientist at the University of Toronto, wants to fix that with an app designed to help the memory-impaired recall those valuable experiences.
As anyone who has studied for an exam knows, it’s nearly impossible to retain information from a single exposure. But it’s also impractical to continually re-narrate events to yourself in order to remember what just happened. Instead a region of the brain called the hippocampus does this for you, by replaying the patterns of neural activity that encode a significant event – just as you might recite the contents of a shopping list. These are broadcast throughout the brain over the following days, strengthening the neural connections involved in crystallising the event into a long-term memory. Impaired hippocampal function prevents this happening.
The US Department of Defence has begun exploring the use of neural implants to restore this capacity in soldiers with traumatic brain injuries. Barense’s solution requires nothing so drastic as surgery. Her app, called the Hippocamera, encourages users to record events, then prompts them to review these videos six times a day at three times the original speed, mimicking the natural pace of the hippocampus. In early tests, the app improved the ability of the average healthy participant to recall the details of an event after a lapse of three months by 40%. A trial is now in progress with Alzheimer’s patients. Since the invention of writing, we’ve been using technology to outsource memory; now it’s being brought in-house.•