As we all know, data can be transferred through cables using electrical pulses transferred into binary codes. My question is, is it possible to transfer data in a similar manner but through the human body? Basically, can we act as a cable? The answer I am looking for is if it is theoretically possible or not?
If we can send data to a space craft a billion (maybe less, maybe more) miles away (namely voyager) undoubtedly we can pass data thru the human body. The answer is YES.
Given that peope serve under some circumstances as ad-hoc antennae... it's not a question of theory at all. It happens. It happens a lot.
Neurons transmit information all the time. For example, from the brain to muscles following intricate pathways including the brainstem, which connects to the spinal cord. In the end, cells respond only at a certain threshold called the action potential:
Here's a model of a neuron:
In addition, chemicals travel from neurons to neurons transmit information. These "neurotransmitters" are slower than the electric signals and their effects are often less specific. In addition, some chemicals can travel from the brain to other organs. These are generally known as hormones. One common example of hormonal signaling is the HPA axis.
The electrical circuits in the brain can be hacked through genetic alteration of neurons, making them respond to light. The potential of optogenetics for future therapeutic applications has been considered by scientists. Today, patients with Parkinson's disease can have a kind of brain pacemaker that provides deep brain stimulation through electrodes, basically compensating for the low neurotransmitter count by plugging into the information circuit for posture and movement.