What are the specialized nerve endings that respond to temperature and touch?

The skin contains three basic types of nerve endings that are sensitive to temperature and touch: free nerve endings, hair follicle receptors, and encapsulated endings.

1. Free nerve endings: Unmyelinated dendrites of sensory neurons end freely in the skin, hair sheaths, and other tissues to detect a variety of stimuli including pain, temperature and itching sensations.

2. Hair follicle receptors: Hair follicles have root hair plexuses around the hair root and Merkel discs around the upper part of the follicle. The root hair plexuses are important in the sensation of hair movement, while the Merkel discs respond to steady pressure.

3. Encapsulated endings: These are specialized structures within the skin that encapsulate the ends of sensory nerve fibers:

* Meissner’s corpuscles respond to fine touch, vibration and pressure.

* Ruffini’s endings are important in the sense of warmth.

* Krause end-bulbs respond to cold and pressure.

* Free nerve endings respond to pain, itching and temperature extremes.