Pawel Mildner / The New York Times
Tuesday, Feb. 13, 2018 | 2 a.m.
Decent memory is a matter of livelihood, of independence, most of all of identity.
Human memory is the ghost in the neural machine, a widely distributed, continually changing, multidimensional conversation among cells that can reproduce both the capital of Kentucky and the emotional catacombs of that first romance.
The news last week that scientists had developed a brain implant that boosts memory — an implantable “cognitive prosthetic,” in the jargon — should be astounding even to the cynical.
Certainly, app developers probably are already plotting yet another brain-exercise product based on this latest science. Screenwriters working on their next amnesia-assassin scripts got some real-life backup for the pitch meeting.
The scientists are in discussions to commercialize the technology, and so people in the throes of serious memory loss, and their families, likely feel a sense of hope, thin though it may be. These things take time, and there are still many unknowns.
But for those in the worried-well demographic — the 40-is-the-new-30 crowd, and older — reports of a memory breakthrough fall into a different category.
What exactly does it mean that scientists are truly beginning to understand the biology of memory well enough to manipulate it? Which reaction is appropriate: the futurist’s, or the curmudgeon’s?
The only honest answer at this stage is both.
The developers of the new implant, led by scientists at the University of Pennsylvania and Thomas Jefferson University, built on decades of work decoding brain signals, using the most advanced techniques of machine learning.
Their implant constitutes an array of electrodes embedded deep in the brain that monitor electrical activity and, like a pacemaker, deliver a stimulating pulse only when needed — when the brain is lagging as it tries to store new information.
When the brain is functioning well, the apparatus remains quiet.
“We all have good days and bad days, times when we’re foggy or when we’re sharp,” said Michael Kahana, a psychology professor at the University of Pennsylvania and senior author of last week’s report.
He added, “We found that jostling the system when it’s in a low-functioning state can jump it to a high-functioning one.”
If this system, once refined, one day provides support for people with extreme deficits, it will sharply improve lives (insurers willing). The older person with creeping dementia will have more years living independently. The veteran with traumatic brain injury may regain just enough sharpness to find a decent job, or a career.
For most everyone else, the central discovery behind the device — that goosing a wandering brain can make it somewhat sharper — is already deeply familiar. Humans have been doing this deliberately, and forever: with caffeine, nicotine, prescription drugs like Ritalin, or more virtuously, with a brisk run around the park.
“We have good evidence that things like nicotine and aerobic exercise improve some aspects of attention,” said Zach Hambrick, a professor of psychology at Michigan State University. “The stimulation may be activating some of the same systems, only more directly and precisely.”
One such ability that people with extraordinarily precise memory have in common is known as selective attention, or “attentional control.” In a common measure of this, the Stroop test, people see words flash on a computer screen and name the color in which a word is presented.
Answering is nearly instantaneous when the color and the word are the same — “blue” displayed in blue — but slower when there’s no match, like “blue” displayed in red. The men and women who compete in memory competitions score very highly on such tests and often do so well into their 30s, when the ability is typically on the wane.
This skill is partly inherited, but psychologists have shown that just about anyone can stretch his or her native ability using the same technique that the memory champs do: mentally arranging new names, facts or words in a deeply familiar place — along subway stops, for example, or in a childhood room.
In one continuing study, researchers at Washington University in St. Louis trained a group of 50 older adult volunteers to memorize word lists using location imagery — a so-called memory palace.
“One woman in her 60s got to where she could recall more than 100 words in correct order,” said David Balota, who collaborated on the study. “Others were well up to 50 and 60 words.”
And all without surgery, or Ritalin.
But there was a catch. “That ability didn’t transfer to any improvement in general cognition, like the ability to concentrate, to store new information without using the technique, or speed of processing,” Balota said.
In short, ramping up the ability to recall lists of facts, whether with use of an electric brain implant or imagery-based training, may mean nothing for overall quality of life in people whose memories are functioning normally.
It is in those with serious deficits that the equation changes.
A device that even partly corrects those injuries might keep crucial details — who to call for help, how to use the phone, even navigating back and forth to the bathroom — firmly lodged in mind. For now, that is where a brain implant is most relevant.
In the years to come, scientists are likely to turn this new technology to the task of memory retrieval, rather than just storage.
“We find there’s even more variability during retrieval than encoding,” Kahana said — meaning more potential to ramp up performance. When that happens, the game changes.
Giving people with serious deficits a way to master the crucial facets of daily existence would certainly be a medical advance.
But giving them, and others, a more vivid and deeper reach into the vast pool of what they already know — well, there are angels and demons buried there, in addition to facts and names.
That will be a real-life screenplay we should all watch carefully.