By my count, there are three kinds of brain fitness programs--and, sorry to say, very little scientific evidence that they work.
There are games and puzzles that are marketed as being mentally stimulating and therefore good for your memory; there are online programs that build exercises around specific parts of memory, like visual memory, or processing speed, or digit span, and that are meant to mimic parts of the IQ and neuropsychological tests; and there are programs that start with a different premise altogether—that memory problems can’t be fixed by getting better at memory-related activities directly, but by addressing the root cause of the memory problem.
The first two kinds of programs are what’s commonly available. They work off the premise that your mind is a muscle that can be toned and bulked up. This is a common perception and it’s a useful and helpful metaphor., especially if you accept the idea of “cognitive reserve”—that you can essentially “bank” neural pathways throughout your lifetime buy engaging in the activities of life itself, so that when your brain is under assault from, say, Alzheimer’s or stroke, some of those pathways can be blocked off and there will be plenty others on which to rely. I like to think of a brain with cognitive reserve as the map of Manhattan—if the Lincoln Tunnel is closed there are still plenty of other ways into the city—and a brain without cognitive reserve as the map of South Dakota—not a lot of roads there, so if one is closed it’s a long detour to find another.
Cognitive reserve is a hard thing to prove conclusively, but the correlation studies are strong, and if you’re interested in learning more about it, check out the work of Dr. Yaakov Stern at Columbia University. As I’ve mentioned before, there’s very little clinical evidence linking games, puzzles and brain software to better scores on memory tests or, more importantly, to better functioning in life. In part this is a function of the testing process itself—it’s expensive to do it right and not a lot of companies are going to invest in a full-fledged clinical trial.
About two years ago, the Journal of the American Medical Association published the results of a trial of various kinds of cognitive training on older adults. The question was: could structured cognitive exercises help people with the activities of every day life. The answer was: not much. The more than 2000 participants were divided into four groups, a control and training for memory (verbal episodic memory), reasoning (inductive reasoning), or speed of processing (visual search and identification); with booster sessions at 11 and 35 months after training in a random sample of those who completed training. Interestingly, only the group that had been given reasoning training reported an improvement in the tasks of everyday living. On the other hand, the group that had been given the processing speed training plus the booster training did improve on tests of speed processing, though this didn’t seem to translate past the testing room.
I like to think of speed processing as the equivalent of mental reflexes. The effect may be so subtle than participants did not notice it in their day-to-day activities. In my own experience, as my processing speed increased from doing cognitive exercises, I was sometimes able to win a game of ping pong against my husband. This is not inconsiderable in our house, but maybe not exactly what the researchers meant when they asked the subjects if the training had improved their lives.