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            Emotion can be described as an excited state of mind or moving of the feelings in reaction to certain thoughts or stimuli. They can be positive as well as negative. The positive emotions are those which make a person happy. Love, happiness, pleasure, pride and success etc. can provide the basis for positive emotions. On the contrary, negative emotions make a man sad and unhappy and they are manifested in the form of anger, fear, hatred, disappointment etc. The negative emotions are basically harmful and sometimes lead to self-destruction.

            Many doctors believe that the newborn babies or neonates have no emotions at all. They learn them through their environment and socialization just as they learn to walk and talk. A young child, for example, may not be afraid of a growling dog or a snake unless it bites the child. Then he may develop a fear, as he gradually learns about their aggressiveness and avoid them in future. 

            Emotion is sometimes considered as opposite to reason or rationality when it results from passions. This case arises when actions are more spontaneous and performed without a reasonable control over one’s mind at that time. The emotional activity is an expression of one’s past learning and experiences.

            Emotions cause many chemical changes in the body which is a part of the body’s defence mechanism. For example, if a person is in a dangerous situation, his adrenal gland sends a hormone called adrenaline into his blood stream. As the blood travels, the adrenaline makes his heart beat faster, sending more blood to his brain and muscles. At the same time, more sugar enters his blood to give his body extra energy to handle the situation.

            The emotional disturbances can cause various physical ailments like asthma, stomach ulcers, rheumatoid arthritis (stiffness of the bone joints) and hypertension. Hysteria is also a result of emotional disturbances. In this disorder, the patient feels that some part of his body is paralyzed though the organ is actually not paralyzed and the patient loses control over him and becomes repetitive in his actions.

            Emotion is viewed in a context of subjective experiences, expressive behaviours and the activity of the nervous system which we call the neurochemical activity. 

          A reflex action is an automatic nervous action in which a stimulus causes a rapid response. For example, if a person accidentally touches a hot stove, he would immediately jerk away his hand before he has time to think about it. In this case, the hot stove is a stimulus, and the jerk is the response. 

          Reflexes, such as the ‘pupil reflex’ are quite common. When a bright beam of   light hits a person’s eye, his pupil automatically becomes smaller. And if the light is taken away and his eyes are shaded, the pupil returns to its normal size. Here the light acts as the stimulus and the reaction of the pupil is the eye’s response.

          Reflex actions are of two types: unconditioned and conditioned. Unconditioned reflex actions are exemplified by the reflex tests of the physician. When a doctor tests a person’s reflexes, he makes sure that the different parts of his nervous system are functioning properly. One reflex action frequently tested is the knee-jerk action. In this the doctor lightly strikes an area just below the knee cap with a rubber hammer. This causes the lower part of the leg to jerk upward suddenly. This is because the nerve impulses move via the spinal cord directly to the leg muscle and are not controlled by the brain. Such reflex actions are called ‘unconditioned reflex actions’. These take place without any special learning or experience. 

          The conditioned reflex actions are a result of particular internal or external stimuli. Such conditioning process was popularized by the Russian physiologist I.P. Pavlov and his associates. Pavlov believed that whenever there was a response to a particular stimulus, a kind of reflex was established in the brain. However, most psychologists today believe that the mechanism of learning is much more complicated than explained by him.

          Now the question arises what causes a reflex action? To explain in simple terms, four basic processes are involved in a reflex action. These are: reception, conduction, transmission and response. The stimulus is received by receptors (nerve endings). Energy from the stimulus is changed into nerve impulses and carried from the receptor to the central nervous system. The nerve impulses are then sent to the motor nerves. The motor nerves control muscle action, causing the muscles and glands to respond (act). Most reflex actions, however, are much more complicated and also involve other parts of the nervous system like brain.

          More than 90% of all the actions are performed by man’s nervous system and reflex actions.  

          A tranquillizer is a drug that calms a person’s mind. It is mostly used to reduce tension and anxiety. It does this without putting one to sleep. Unlike a sedative, it does not induce sleep. However, its tranquillizing effect may sometimes put the person to sleep. If given in the right dosages, most depressants and sedatives can act as tranquillizers.

          The first member of the tranquillizer drug family was phenothiazine. This was first synthesized in the 1880s, but its potentiality remained unrecognized for nearly 70 years. In 1950, some French researchers synthesized the first widely-used tranquillizer — chlorpromazine. Chlorpromazine and its allied drugs lower the activity in certain areas of the brain that are concerned with emotions, such as the cortex, thalamus and hypothalamus. They also have a sedative effect. The benzodiazepine drugs produce a lighter tranquillizing effect and include volium and Librium.

          Tranquillizers are being used for many mental illnesses such as schizophrenia and anxiety neuroses. Chlorpromazine has been used especially in the treatment of schizophrenia. 

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          The age-old maxim, ‘An apple a day keeps the doctor away’ was a polite way of saying that this habit would help to prevent constipation and other related ailments. Since it was believed that the juice of a raw apple aided the fermentation of undigested foods.

          Although one might question such a sweeping statement in the highly advanced modern times, none can deny that apples are good for health because of their high nutritious value. Some people have modified this statement and suggested that ‘it keeps the dentist away more than the doctor’. According to the dentists, biting on a crisp apple is an effective way of removing food particles from between the teeth. Eating an apple after meals and cleaning the teeth in the night and morning is the best way to keep the teeth healthy. 

          Apples contain Vitamins A and C. They are rich in cellulose and carbohydrates. They also contain some minerals. This implies that apples also help in the prevention and cure of several deficiency disorders, e.g. scurvy, night blindness etc. as well as in purifying blood. They also aid in healing, protection against cold and building of healthy bones, teeth and gums.

          The presence of these food sources and their utility in keeping the body fit and healthy justifies the old adage.

          Apples are eaten raw, both for taste as well as its beneficial values. An apple contains about five-sixths water and the remaining one-sixth consists of sugar, ascorbic acid (Vitamin C) and other acids, and rough indigestible matter. Apart from their nutritious value, apples are also used for cooking sweet dishes, and cider is brewed from fermented apples.

          Apples belong to the family of Rosaceae. In the ripen state they are usually red, yellow or green. Apples grow in temperate zones, in relatively cold weather. By the end of 300 A.D, a Roman writer named 37 varieties of apple and today hundreds of varieties are available with varying sweetness. 

            In our day-to-day life we often come across situations where we get the knowledge of an event before it happens or become aware of something that is out of sight, or can read what another person thinks, etc. This happens without the use of any of the five senses — sight, hearing, smell, taste and touch. Hence we call this ability as Extrasensory Perception (ESP) which literally means ‘awareness outside the senses’. Some people also call it as the ‘sixth sense’. Usually we perceive everything around us with the help of our five senses but ESP provides us with information which are normally not conveyed by any of the five senses.

            But the scientists as well as psychologists are not unanimous about the existence of ESP. The controversy is that this phenomenon can be explained in other ways and science has not been able to either explain or prove this. 

            There are four basic areas of experiments in the field of extrasensory perception. These experiments involved telepathy, clairvoyance, precognition and psychokinesis. The ESP researchers use a special deck of cards. This deck is made up of 25 cards with certain symbols such as a cross, a circle, a star, wavy lines and a square etc. At the Duke University (North Carolina) Professor J.B. Rhine has published a book titled Extrasensory Perception (1934) after carrying on experiments on it for more than three decades.

            In the telepathy experiments, a person tries to ‘read the mind’ of the one conducting the experiment by guessing the cards. Telepathy involves sending of thoughts, feelings or knowledge from one person to another without any apparent medium. It is often called thought transference.

            Clairvoyance is the state of being mentally aware of something that is out of sight such as an event or a person, without the telepathic help from any other person. In the clairvoyance tests, a person identifies cards through various methods without seeing them. When the number of current guesses is higher than the average person achieves, it suggests that the person has extrasensory perception.

            Precognition is the knowledge of an event, by means of telepathy or clairvoyance, before it takes place. In the precognition tests, by using cards or a dice, an attempt is made to predict a sequence of events before they actually occur.

            Psychokinesis is the psychological control of physical objects. For example, while tossing a coin, a person might concentrate on the ‘heads’ and cause it to appear.

            It is said that all the people do not possess such powers to see the truth directly without reasoning. There are many examples of people possessing such abilities and ESP is a convenient way of acknowledging this.

            The scientists have been studying this phenomenon because they feel it has enormous potential for a fruitful research. For example, a person with ESP abilities might be able to predict future wars, locate valuable mineral deposits or even accomplish other things of great importance.