- June 16, 2012
- Posted by: essay
- Category: Sample essay papers
People live in difficult and changeable conditions; life demands from man some skills of orientation in surroundings, skills of adaptation to surroundings’ conditions. Man’s cognitive activity begins from the sensual reflection of the world with the help of senses and perception.
Sense ”“ is a reflection of some specific qualities of things or phenomena. This reflection takes place because of the influence of outer irritants on organs of perception. With the help of senses man can perceive different colours, sounds, smells, taste, weight, warmth and cold. Senses also give the information about the changes in human body: moves of hands, legs; posture; functions of inner organs. Senses are the regulators of man’s behavior. For example: perceiving some weather changes (sensing warmth, cold or wind), man can adapt himself to the surroundings.
Imagery sphere of a man (when there is some sense man has some image about what can be an irritant) develops and forms in society, in activity, communication, studying. That is why, man has some specific knowledge about characteristics and qualities of things or phenomena. For example: sense of cold. Man can understand that ice is cold when he touches it, but also man knows that ice is cold from the previous experience of other people.
There is a system of analysators (which analyse signals) each of them forms senses of some specific quality: visual, auditory (acoustic), temperature, pain, muscular and others. Any analysator consists of receptors, nerves, which conduct signals and central part of cortex. Some analysators have specific auxiliary structures, which help to conduct irritant signal. They are, for example, cornea, crystalline lens, ear-drum and others. Together with receptors they form organ of perception. Senses and perception have two main functions in human life: they inform about the surroundings peculiarities and they organize human actions according to the surroundings changes. For the effective fulfillment of these functions senses and perception have to reflect situation correctly, man’s actions have to be adequate to situation. Senses reflect all main characteristics of things: qualitative, quantitative, spatial and temporary. Opinion that man has five senses: sight, hearing, taste, sense of smell and sense of touch is not correct.
There is also temperature sense, pain sense. The intermediate position between senses of touch and hearing sense has vibration sense. Senses reflect the qualities of irritants. For example, retina transforms electromagnetic waves into the physiological processes. Simultaneously, receptors of retina awaken because of the influence of specific length waves, and then we can see some colour. Influence time of irritant on organs of perception is reflected in temporary characteristics of senses. It is very interesting that we have some sense later than irritant begins its influence and for some period of time we still have sense, when irritant stops its influence. This inertia of senses is called after action.
Mental images are formed when man receives and processes information. On the physiological level information interaction (man and surroundings) we can see as a reflex. When man touches for example fire, he jerks hand back.
Irritant signal reached the cortex, then it was processed, and then signal went back to receptors and changed their actions and stimulated motive zones. Due to the cyclic processes of information processing at different levels of nervous system people can sense quality and intensity of irritant, its location and duration of influence.