Also briefly, doesn't necessarily have to be an equation that the system is learning. Any sequences of samples could be assigned an answer/label and can have overlap with other data types of samples. So an image can be associated with a sound or a word etc, and presenting one or part of the sample could trigger the recall of any of the samples associated with the given sample. So the word tiger triggers the recall of the image, the sound, any context it is found in, etc.
