Possible principles underlying the transformation of sensory messages

This paper suggests the Efficient coding hypothesis (redundancy-reducing hypothesis).

A wing would be a most mystifying structure if one did not know that birds flew. … I think that we may be at an analogous point in our understanding of the sensory side of the central nervous system.


  1. Sensory relays are for detecting, in the incoming messages, certain “passwords” that have a particular key significance for the animal.
  2. They are filters, or recoding centers, whose “pass characteristics” can be controlled in accordance with the requirements of other parts of the nervous system.
  3. They recode sensory messages, extracting signals of high relative entropy from the highly redundant sensory input.