A short but interesting book, first published in 1957, is entitled 
The Computer and the Brain by John von Neumann.  It was intended
to be given as a Silliman Lecture at Yale University but, alas,
the author passed away before completing the manuscript.

The rudiments of digital and analog computations are discussed, 
then mechanisms of the brain.  The comparisons are remarkable in 
that the brain is a slower speed parallel machine while our 
conventional computers are high speed serial devices.

To quote "it (control) can, in particular, change the orders
that control its actions.  Thus,all sorts of sophisticated 
order-systems become possible, which keep successively modifying
themselves and hence also the computational processes that are
likewise under their control."

This self-modifying control is out of favor now, but it taken 
together with the parallel processing may be a way to opening
new ways of computing.  It feels that computing has been stuck
in the same paradigm for the last fifty years and no closer to 
providing human-like interfaces than in the beginning.

This is an interesting and stimulating book.  I probably wouldn't
buy it but if you find it somewhere it might be of interest.