Sense

sense

2004

Sensory system is a system in human organism which is responsible for origin of sense when some corresponding irritant is acting . It provides usage of characteristics of environment for behavior organization Sensory system includes a receiver (which transforms energy of external irritant into nerve energy , conductive paths (inside of which this nerve energy passes ) and central (brain ) ending (where transformation of nerve energy into sense takes place

Sense is a reflection of characteristics of subjects in objective world which appears during their direct influence the receptors . Usually we

br distinguish five sensory systems . They are hearing (sound , sense (tactile /skin ) touch , sight (vision , taste and smell

In the hierarchy of five senses sense of touch usually takes last place as the most rude and low-lying , whereas the higher places are given to sight and hearing . Still , I want to tell about sense of touch . It is (as it directly perceived its subject via touch ) the most contact of all senses - together with taste . Touch doesn 't leave place to sign , because is directly leads the thing to organ of its perceiving , to the borders of body , the receptors of skin

Sense of touch is a complex of senses , which appear during irritation of several kinds of skin receptors . Different receptors react in different way : some of them perceive temperature irritants , some of them - touch and pressure at skin (tactile receptors . Receptors of touch (tactile receptors ) can be of several kinds also : one of them are very sensible and are stimulated when you press skin at your hand for 0 .1 micrometer only the others react only after strong pressure . In average for 1 sq cm there are approximately 25 tactile receptors , although at the skin of face , fingers and tongue there are much more receptors . Besides , hair which covers 95 of our body is also sensible to touch . There is a tactile receptor at the base of each such hair

Information from all there receptors is collected into spinal cord and by conductive paths of white substance it reaches nuclear of thalamus and from there reaches higher center of tactile sensibility - area of back central convolution of cerebral cortex of big hemispheres

Usually blind people have well-developed sense of touch . Thanks to it they have possibility to get acquainted with different objects of environment . Perceiving receptors which are located at our feet help us to orient in space during running , walking , standing , etc . Sense of touch allows us preventing many damages of our body . When we touch something very sharp or very hot , we reflexively move away from the irritant

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sense

DATE : September 12 , 04...