Have you read smolensky's harmonium paper? It's the first restricted Boltzmann Machine -- and I believe elman and smolensky were colleagues with hinton back at UCSD (with rumelhart and Don Norman, et al).

The approach was focused on presymbolic processing -- and tried to optimize harmony. Harmony was, interestingly, the first mathematical model of the mind (by Pythagoreans/platonists in ancient Greece). It has a lot going for it these days, too, to understand oscillatory coupling in neural circuits. I learned recently that brain waves are harmonics (frequency doublings), which somehow I missed before!