Re: Many sensory receptors respond preferentially to changing stimuli.

If I understand your question correctly, I believe that what you are asking 
about is what Gregory Bateson calls the “difference that makes a 
difference”, which in concrete terms is information.   According to 
Bateson, our sensory system (and that of all other animals and perhaps 
plants) can only operate with stimuli that change.  The unchanging is 
imperceptible. For example, when you look at something, the object that you 
are observing is not moving, but our eyeballs have a continuous tremor 
called “micronystagmus”, which cause the optical image on the retina to 
move relative to the rods and cones.  A more concrete  example may be that 
of depth perception, which occurs with the difference in information 
received by one retina as opposed to the other.  In terms of plants, 
Bateson uses the example of a seedling growing more rapidly on its darker 
side (difference between light and dark), thus bending towards the 
sunlight.

Another example that Bateson often used to explain this phenomena was that 
of a heavy chalk mark on a black board. If you place your finger 
vertically on this spot, it will be difficult or impossible to feel it, but 
if you run your finger on the board starting form a position either left or 
right of the mark, it will be obvious where the flat black board ends and 
the chalk “bump” begins (e.g., a change in surface).  Bateson suggests that 
in the external material world, the cause of some event will always be some 
type of force. But our sensory world can only operate with change.

Although Bateson’s explanations are often a merger of science and 
philosophy, the study of quantum mechanics suggests that at certain levels 
of inquiry, these two seemingly incompatible fields are sometimes difficult 
to differentiate.  If you would like to learn more about Bateson or his 
ideas, I would suggest that you read his books: 1) Mind and nature: A 
necessary unity; 2) Steps to an ecology of the mind.  Also, if you are 
interested, I wrote a paper about his theories many years ago which is 
found here: Cullari, S., & Redmon, W.  Bateson and behaviorism. 
Psychological Record, l982,  32 , 349-364.