“Program level” is a metaphor, an informal supposition that certain neural circuits in the brain are functionally analogous to functions in computer programs.
Computer programming depends upon libraries and sub-libraries of functions, idioms, routines, algorithms. Broadly speaking, these are general patterns for solving specific problems. Programming organizes them into systems that make use of those patterns to solve specific problems or otherwise produce desired outputs given certain inputs. Maybe there are abstract general-purpose sequence-control loop systems that are employed by a variety of higher-level systems to control their diverse input requirements. Maybe there are abstract organizations of these into something corresponding to libraries and sub-libraries of functions, idioms, routines, and algorithms. As a general rule, computer programs, algorithms, routines, idioms, and functions as found in the computer science world do not implement negative-feedback control loops. In HPCT I should think every such function would be a control loop, but maybe someone has good reasons for the postulated Program level to be like program libraries in a computer.
There are other reasons that it is extremely difficult to make a direct analogy from posited neural structures to program structures. The appearance of these structures differs so much from one programming language to another. The ‘program language wars’ have long been a contested effort in defending ‘the devil you know’. This amusing talk by Andreas Stefik on actually applying scientific methodology to the learnability and human efficiency of computer programming languages (in the form of human factors research and usability testing) lays bare how and why computer programming languages are demonstrably counter-intuitive. “Counter-intuitive” seems to identify aspects in which they do not accord with how we think (a proposition complicated by the tangled and often denied relation of computer languages and of mathematical logic systems in general to language). A deep dive into Structure and interpretation of computer programs (SICP) can clarify the differences. It’s expressed in terms of one ‘religion’ (Lisp/Scheme). (Also here under creative commons.) A Javascript edition was published this year (2022). I haven’t done anything with that since I left BBN in 1994 and it’s not in my direction of work now, so I can’t be much particular help other than to set the signpost.
Some discussion of Rick’s demo is here and here.
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