IASP Definition of Nociceptive Neuron
A central or peripheral neuron of the somatosensory nervous system that is capable of encoding noxious stimuli.
Definitions You Might Have Seen
Nociceptive Neuron or ...
Danger detector or receptor that detects danger and sends danger messages to the brain.
Threat detector or receptor, that sends threat messages to the brain.
Pain receptor that sends pain messages to the brain.
Part of an alarm system warning you of danger.
A sensory neuron that detects pain.
Isn't this the same as Nociceptor?
It's a bit confusing I'll admit. Nociceptive Neuron and Nociceptor are often referred to as the same thing which is why the 'other' definitions you might have heard remain the same as for nociceptor. There are some key differences. A neuron is an electrically excitable nerve cell. It is the main component of nervous tissue classified according to function. Sensory, motor, and interneurons. A typical neuron consists of a cell body (soma), dendrites, and a single axon. Here's another short, neat video.
Remember transduction and encoding? Well in the IASP definition the nociceptive neuron is not a transducer (convert sensory to electrical), but it does encode (converts to a different system of communication). Nociceptive neurons, unlike nociceptors are also found in the CNS.
What does this mean practically? Well it means we're talking about a nociceptor that detects external and internal noxious stimuli from the periphery, and a nociceptive neuron that exists within the peripheral and central NS to transmit information.
Consider, if you will
That nociceptive neurons are within system or apparatus (we'll get there soon) communicators. Initial neurotransmitter information they pick up through their dendrites comes from nociceptors with free nerve endings that are activated by noxious stimuli.
Nociceptive neurons pass that information to each other. This dendritic neurotransmitter activity takes place at the synapse, and though we're not going to go into that level of complexity yet, it's enough to know that the information passing through the synapse is subject to change.
What do changes to encoded information at the synaptic interface of nociceptive neurons do to the idea of predictability and expectation for pain? Think about it. You sprain an ankle, it swells, but it doesn't hurt nearly as much as you though it was going to. You go over on your ankle just a little bit, there's no swelling to speak of and the joint remains stable but it hurts like nothing you've felt before.
Does this process of message transmission and change (being one of many possible) help you understand some of the challenges facing people in pain as they describe experiences that don't meet our initial expectations?