With the advance of information technology, the computer has become 
a model for the brain, replacing earlier ones, such as the telephone 
exchange and hydraulic machinery. But what kinds of computations 
does the brain perform?
What we know about its structure and function imposes constraints. 
We can analyze the consequences and implications of these constraints 
to arrive at new insights. Thus we are led to a view of multivariable, 
broadly tuned single cells, overlapping computational areas and 
distributed representations of functions and operations.

Recent findings from imaging and neurobehavioral studies support 
the idea that brain programs or representations are dynamic and 
distributed and that brain-body interactions are inseparably linked. 
It is proposed here that the primary constraint on representations 
is that they be in brain-body correspondence with the appropriate 
task or operation and within that constraint there is considerable 
latitude in the ways these programs can be generated and regenerated.
Based on these viewpoints, this paper presents an outline of principles 
and their illustration by quantitative treatments.