Sensations need Receptors

I've decided I need to model "sensations" as well as "perceptrons" but the problem now is what picks up a sensation? Here again psychology offers some helpful terminology: receptor. Just like the receptors in the back of your retina - some sensors fire automatically in response to a stimulus. These low level sensors are important for classifying low level sensations (e.g., ___ ).

So practically speaking, in The Goo a Receptor generates Sensations which in combination with other Sensations may be picked up by a Sensor that may in turn "fire" a Perceptron (e.g., I see a red line).

Snipping The Gordian Knot

I recently painted myself into a corner with the design rule "everything must be a perceptron". The problem is that just like with human perception, events need to bubble up from their source until they reach a threshold and "fire". A perceptron is a perceptual event that has fired - but how do I model the preconditions for a perceptron to fire? I need something smaller than a perceptron.

Borrowing from psychology again:

Sensation is the first stage in the biochemical and neurologic events that begins with the impinging upon the receptor cells of a sensory organ, which then leads to a perception.

Sensational!

So instead of tying the design in knots trying to model perceptrons with perceptrons I've snipped the proverbial Gordian Knot and now lesser perceptual events are simply sensations that can chain sensors together to make a perceptron.