What are cutaneous polymodal nociceptors activated by?

These neurons are excited by both noxious and non-noxious cutaneous and/or visceral stimuli (polymodal nociceptive neurons). These neurons are activated by a variety of noxious stimuli (mechanical, thermal, chemical, etc.) and respond incrementally to increasing intensity of the stimuli.

What is the role of nociceptors they are?

Specialized peripheral sensory neurons known as nociceptors alert us to potentially damaging stimuli at the skin by detecting extremes in temperature and pressure and injury-related chemicals, and transducing these stimuli into long-ranging electrical signals that are relayed to higher brain centers.

Are nociceptors myelinated?

The axons associated with nociceptors, in contrast, conduct relatively slowly, being only lightly myelinated or, more commonly, unmyelinated.

What information does the nociceptor relay to the brain about stimuli below threshold?

Answer and Explanation: The nociceptor does not relay any information to the brain about stimuli below the threshold.

Which is characteristic of C-fibers?

C fibers respond to stimuli which have stronger intensities and are the ones to account for the slow, lasting and spread out second pain. These fibers are virtually unmyelinated and their conduction velocity is, as a result, much slower which is why they presumably conduct a slower sensation of pain.

Are there nociceptors in the brain?

Though your brain does not have nociceptors, there are nociceptors in layers of tissue known as the dura and pia that serve as a protective shield between the brain and the skull.

How do nociceptors send pain signals?

They respond to tissue injury or potentially damaging stimuli by sending nerve signals to the spinal cord and brain to begin the process of pain sensation. Nociceptors are equipped with specific molecular sensors, which detect extreme heat or cold and certain harmful chemicals.

What are nociceptors stimulated by?

Nociceptors can be activated by three types of stimulus within the target tissue – temperature (thermal), mechanical (e.g stretch/strain) and chemical (e.g. pH change as a result of local inflammatory process). Thus, a noxious stimulus can be categorised into one of these three groups.

Does the brain have nociceptors?

Although the brain has no nociceptors, many of the other structures in our head do, including blood vessels, muscles, and nerves in the neck, face and scalp. Headaches are caused by problems with these structures.

What information does the nociceptor relay to the brain?

Answer and Explanation: The nociceptor does not relay any information to the brain about stimuli below the threshold. This is because stimuli below the threshold do not…

Which ion channel is responsible for the rising phase of the action potential and why?

The rising phase is caused by the opening of voltage-gated sodium channels. These ion channels are activated once the cell’s membrane potential reaches threshold and open immediately. The electrochemical gradients drive sodium into the cell causing the depolarization.