Page 62 - Human anatomy COMPLETELY DONE1

THE SENSE OF TOUCH. SKIN RECEPTORS

By touch (tactile sense), a person can determine the size and shape of objects by
touch. Touch is a complex feeling, as it includes the ability to feel touch, pressure,
vibration, temperature (cold and heat), as well as pain.
Such a variety of perceived information is provided by several types of receptors
localized in the skin and mucous membranes. Therefore, the skin can be considered not
only an organ that performs a covering function, but also consider the skin as a sensory
organ (figure 40).
The skin receptors differ in their structure. There are receptors that represent
nerve endings. Other receptors have capsules consisting of connective tissue cells.

Figure 40. Skin receptors

Receptors sensitive to light touch and low pressure are located in the upper part
of the dermis. Larger receptors that respond to bruises and severe pressure are located
deeper in the dermis and are almost all surrounded by capsules. Heat, cold and pain are
perceived by branching nerve endings that do not have capsules, which are located on
the border between the epidermis and the dermis.
As a result of irritation of the skin receptors, excitation (electrical impulse) is
sent first to the spinal cord. Further along the pathways of the white matter, signals are
transmitted to the nuclei of the thalamus, from there to the highest center of tactile

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