Question

Which sensation can arise when free nerve endings in the skin are stimulated?

Answer 1

Hint: Free nerve endings are unencapsulated nerve fiber mainly found in the skin and have no complex sensory structures. They have different rates of stimulus modalities as well as different rates of adaptations and fiber types.

Complete answer:
The free nerve ending is unencapsulated nerve endings that are found in the skin and stimulate sensations like touch, pressure, stretch, or even danger. Therefore, they work as thermoreceptors, cutaneous mechanoreceptors, and nociceptors and therefore are polymodality. They have different fiber types such as A-delta fibers and C fibers and different rates of adaptations that are rapidly adapting, intermediate adapting, or slowly adapting.

Additional information:
Below are the different types of adaptations, stimulus modalities, and fiber types.
Adaptations:
-Rapidly adapting mechanoreceptors are Meissner corpuscles end-organs, Panichian corpuscles end-organs, hair follicle receptors, and a few free nerve endings.
-Intermediate adapting are some free nerve endings.
-Slowly adapting mechanoreceptors are Merkel and Ruffini corpuscle end-organs and also some FNE.
Stimulus modalities:
-Thermoreceptors are non specialized sense receptors that code changes in temperature.
-Mechanoreceptors are sensory cells that react towards mechanical pressure.
-Nociceptors are sensory neurons that respond to damaging stimuli.
Fiber types:
-Group A and group C nerve fibers are two of the three classes of nerve fibers classified by Erlanger and Gasser.

Note: Free nerve endings or FNE are also known as bare nerve endings. These are mainly afferent nerve fibers that send signals to a sensory neuron and function as cutaneous nociceptors invertebrates to detect stimuli, often resulting in pain. They have no capsulated ends and Complex sensory structures. These are the most common type of nerve ending and are abundant in the skin.