I spent the morning with my son Cody digging dandelions out of our lawn. Some dandelions are easy to spot since they are sprouting yellow flowers, but other dandelions are harder to see. Cody helped me on the hunt. Also, since dandelions spread out, when you dig them out, you need to also look carefully to find the center of the plant to locate the taproot. We filled half of a trash bag full of dandelions.
My brain doing an odd thing now that I am resting. Whenever I close my eyes, I see dandelion plants, a different plant each time I blink. My brain is imagining symmetric top-down images of these plants, with white and red veins radiating from center, festooned with spiked green leaves. This is not how I saw the plants in the garden: I spotted them from far away in diagonal and side-view. But I am now replaying images of dandelions in a abstract symmetrical circular perfection.
What is my brain doing? Neuroscientists have long suspected that memories "consolidate" during rest. But recently, a Nature Neuroscience paper by H Freyja Ólafsdóttir actually measured this! The UCL scientists measured rat brains during 30 minutes of running on a track, and then during 90 minutes of rest afterwards. During rest, the rat brains reproduced the signals of their experience running on the track, but replaying the experience 10-20 times faster than realtime.
It is interesting to contemplate why replay is necessary, or what might be in the transformation between initial experience and replay. For example, when training artificial neural networks, programmers use "training set augmentation", applying transformations on the training set data without altering labels, in order to generate a larger training set. Is this what consolidation is all about?
Or it is the opposite? My brain seems to be imagining canonicalized dandelions, centered in the field of view with perspective skew removed. Is it canonicalizing the view for better compression? Should we be trying to do the same thing in artificial neural networks?