The other day I’m loping down the Historic Trail on Mount Sutro, and as I run past this particular point on the path, the podcast episode that I had listened to some seven days prior begins replaying in my brain. Almost verbatim. And I realize that this mental replay is nicely synchronized with where I was on the trail on the first listen. (Nota bene: mine is by no means an exceptional memory.)
You may know (I did not) that the phenomenon whereby our brains associate memories with physical surroundings to facilitate their subsequent retrieval is known as context-dependent memory, and that the underlying physiological mechanism is thought to involve the hippocampus, which is able to create a kind of “neural map” that allows memories to be organized based on their location and tagged with contextual cues (sights, sounds, smells). The method of loci exploits this faculty where “memory athletes” can construct a “memory palace” that allows them to recall and recite, for example, an insane number of digits of pi.
But, of course, in this situation it was nothing so deliberate. The picturesque, eucalyptus-scented, birdsong-adorned urban trail was put to good work as a mnemonic by my brain without my realizing it. Which is fascinating: that a process that can operate at the unconscious level can encode information so powerfully (i.e., my near word-for-word recollection).
Steve Jobs, Mark Zuckerberg, et al. were on to something with walking meetings (solvitur ambulando): inhale some fresh air, boost your energy level, and maybe best of all, stimulate brain function. On that last point, research suggests that “moderately-intense” aerobic exercise increases the size of the anterior hippocampus and improves memory (or at least staves off hippocampal volume loss and memory deterioration)1, so I’m thinking: pick up the pace and amplify the effects. Ergo, solvitur correndo (it is solved by running)…it being the problem you’re trying to work out; the memory you’re trying to bring into focus; the n-th digit of pi you’re trying to link with a specific point on the trail.
Happy Pi Day.
— ᴘ. ᴍ. ʙ.
Thanks to Lisa Berens and Matthew Brennan for reading a draft of this.
Erickson, Kirk I., et al. “Exercise training increases size of hippocampus and improves memory.” Proceedings of the national academy of sciences 108.7 (2011): 3017-3022. ↩