why not connect to a near neighbor again and again rather than a more distant nerve

[Jsluiman]

Nerves appear to grow to the nearest neighbouring nerve which fits the criteria of: A.) It is a part of the correct chain- a nerve which connects to a sensory neuron carrying inputs dedicated to a sense of touch will not connect to neurons which carry others like taste or smell though they can become a part of a larger bundle of nervous tissue they won't interact. B.) The nerves attaching together have the correct neurochemistry to exchange the electrical action from one cell to the next.

Connecting to further nerves suggests that the nearer nerves were not suitable, and once the connection is established additional nerves will grow to reinforce the connection if the electrical action is greater than what the current chain can sustain efficiently.

[HarmSluiman]

So how are the senses distinguished? Are they destined to be used a certain way or is it more a matter of they are in use and cross connecting between active paths doesn't happen? This become an important characteristic when we consider the current programming practice of declaratively allocating a matrix of neurons and they end up being used for a specific task.

Further to this point, perhaps there are a finite set of senses and each has a specific nerve type and path to the spinal cord or brain. Anecdotally, this matches that there are no pain receptors in the gut or eye, and we don't see with our fingers.

In the eye there are a very specific set of cells to create the optical experience that feed the brain, and following there would be a unique set fo cell for each other sense and in parallel they each have their own perceived location for processing in the brain.

The reason the importance of this question is more than the answer. It starts to define how much "pre-wiring" is needed and done in the body to work as a base for the higher functions and behaviors.

[Jsluiman]

Needs further research, theorizing with current information: Distinguishing between senses is done depending on the information being provided to the system, in the peripheral nervous system reflexive actions are done locally while more complicated things like pain are passed up the chain to be processed in the brain(stem). Intraneurons use action potential of the information they are receiving to decide whether or not it should be passed higher up the chain, and they merge information together to be sent along. I suspect this means that even if you mimicked a pain signal from somewhere in the gut it would either be weeded out before getting to the brain or it would be processed as pain from a normal area with pain receptive cells as there is no end point in the brain correlated for the signal to go to specifically. This would suggest a significant amount of 'pre-wiring' at least in relation to the PNS.

Will do more research and add comments as it develops.