Neurons in the brain, including large pyramidal cells
(as shown above in a macaque), develop connections
that change depending on experience- part
of what makes learning possible.
Image courtesy of brainmaps.org
Merzenich says that some 80-year-olds who have used his program have shown gains that bring their performance into the realm of someone decades younger. “Pre- and post-testing documented a significant improvement in memory within the training group” as opposed to a control group, he reported in an August 2006 paper in Proceedings of the National Academy of Sciences. This finding has yet to be independently confirmed in a peer-reviewed journal. But in recent, as-yet-unpublished research, MIT neuroscientist John Gabrieli has discovered an exciting, plausible explanation for the improvement Merzenich reported. In a controlled, double-blind study sponsored by Posit Science, Gabrieli subjected 12 patients with mild cognitive impairment to fMRI brain scans. Half of the group’s members had used the Brain Fitness Program as prescribed, and the other half had not. Gabrieli found that the group who had used the program showed greater blood flow in the hippocampal region, important in memory, compared with controls. Posit Science is now planning a larger study.
Merzenich says his program works by reversing what he calls the “negative plasticity” of aging. “Older people tend to want an easy life,” he says. “They don’t realize how bad that is for them.” Normal wear and tear gets compounded by sloth and pessimism in this scenario: As people age, the brain starts to shrink, and the cerebral cortex thins. There is a drop in the chemical neuromodulators that speed information across the synapses, and even in the elaboration of dendrites and axonal arbors, the neuronal architecture that supports learning. An older person suffers what Merzenich calls “noisy processing”: bad signal reception, like a radio tuned between channels. Pretty soon, Grandpa finds it increasingly difficult to understand Junior’s rapid speech and in frustration begins to avoid the kid completely. His confidence ebbing, he ducks other kinds of challenges, and his skills slowly erode from disuse—unless he does something to build them back up.
This, of course, is the goal of the Brain Fitness training, which begins with a series of fine-tuning exercises, targeting the rudimentary workings of the auditory system. The intensive and highly repetitive practice—a much more targeted and disciplined exercise than, say, doing crossword puzzles—is meant to overhaul the way the brain receives and interprets information, which Merzenich contends ultimately helps improve the efficiency of how that information is stored. His suggestion is that it is like cleaning the portals of perception, making subtle adjustments that sharpen attention to small or rapid details, building more clarity and focus.
The first exercise plays one of two swooping bird whistles—whooEE! or WHEEoo!—after which the user must mouse-click to indicate whether the sound is moving from low to high or high to low. Next comes another simple test called Tell Us Apart, which requires the user to distinguish between sounds that are closer to human language, like “bo” and “do.” The exercises start out quite easy, growing in difficulty over time. They eventually include drills geared toward improving sustained attention and memory by requiring users to remember the details of long stories.
Success is lavishly reinforced during the training process. A cheery bell rings with each correct answer, while a garbage-can plunk notes mistakes. The program also features two cartoon scientists in lab coats who call out at frequent intervals: “Good job!” “Fantastic!” “Excellent!” and “Now you’re cooking!” Merzenich insisted on these coaches, but after many people found them intolerable, he grudgingly included a feature to mute them. His theory is that the benefit of all this practice and encouragement can be seen inside the user’s skull. The user’s brain is engaged, and his neuronal connections strengthened, while the novelty and reward inherent in the program improve the release of neurotransmitters like dopamine, serotonin, and norepinephrine, which enable plasticity. His signal-to-noise ratio improves. Maybe he finds he is actually interested in what Junior is saying.
A dozen or more companies are promoting methods of memory-saving stimulation. Few have the stature of Merzenich, though.
Spend any amount of time with Merzenich and you start to see reflections of his worldview in his software, which goads users to spare no effort in reaching for their maximum cerebral potential. Even the progressively quicker pace, as users acquire deeper skills, recalls Merzenich’s teaching style. He is famous among his students for a one-word motivational speech: “Faster!”
