Brief notes on Biological Motives from psychological point of view

Biological motives are directly related to individual’s physiological needs, and eating are necessary for individual’s biological survival. Sex is essential for survival of the species.

These are also called primary drives, which are deeply rooted, in our all make-up. Satisfaction of these drives is necessary because our needs certain substances for its growth as well as its day-to-day maintenance with a view to keeping the balance of various physiological as within the body. Some of our most powerful motives, e.g., hunger, thirst, sex, sleep, avoidance of pain, are rooted in our physiological make-up actually regulatory in their nature.

In other words, we can say that many biological needs are triggered departures from balanced physiological conditions of the body. Our body to maintain a balance, called homeostasis, in many of its internal physiological processes. This balance is very important for life.

For example, temperature must not get too high or too low; there must be enough water the body tissues The homeostatic mechanisms are mainly responsible maintaining the acidities, water level, sugar level, temperature, blood pr< and numerous other highly complicated bodily processes. The working of these physiological processes and homeostatic equilibrium of the body are possible by our efforts to supply the requirements of the body.

On the whole, the tendency of motivated behaviour to maintain a balanced condition within the organism is called homeostasis. According to a renowned physiologist, “The living being is an agency of such sort that each disturbing influence induces by itself the calling forth of compensatory activities to neutralize or repair the disturbance”.

There are many automatic mechanisms, which maintain the balanced condition of homeostasis. Consider the automatic physiological control of body temperature at a point of 98.6°F. Our body temperature usually stays around this point because of automatic mechanisms that allow the body to he cool itself. It the temperature of our body rises too high, perspiration the temperature. When the temperature falls, we shiver, causing our body to burn fuel faster to generate extra heat.

Physiologists have discovered that the automatic physiological mechanisms, which maintain homeostasis, are supplemented by regulatory or motivated behaviour. For example, falling temperature creates a drive state to which we respond by regulatory behaviour- putting on a sweater or the doors and so on. So the biological motive states are aroused by departures from homeostasis.

Hunger Drive

Experiments done earlier in the century revealed that the source hunger drive is stomach contractions. This was shown by using subjects who were trained to swallow a small balloon with a rubber tube attached. This was inflated in the stomach and the rubber tube was then connecting kymograph recording mechanism, so that each spasm of the stomach muscles could cause a mark on the smoked drum.

Again, the subject was also asked to press a key, whenever he felt hunger pangs. Therefore, a mark was made on the drum just below the record of stomach activities. The abnormal breathing of the subject was also recorded; hat the investigator could decide whether the spasms represented in the record were due to stomach or abdominal movements. It was found that hunger pangs coincided with stomach contractions, but were not related to movements of the abdominal muscles.

Recent works on hunger drive have revealed that the relationship between stomach contractions and hunger is weak. Both psychologists and physiologists have tried to find other conditions of the body, which trigger hunger.

Some physiologists held that changes in the metabolic functions of the liver when fuel supplies are low provide body’s stimulus for hunger. Here the can signal a part of the brain called hypothalamus that more fuel is needed which triggers hunger drive.

Experimental findings also confirmed that two regions of hypothalamus are involved in hunger drive- lateral hypothalamus venrto-medial area. Lateral hypothalamus is considered to be the excitatory area. Animals eat when this area is stimulated. When it is damaged, animals stop eating and die of starvation. The ventro-medial area is located in the die of the hypothalamus, which is otherwise known as hunger-controlling area. Experimenters consider it as the inhibitory region of the hunger drive.

Experimental studies have shown that when this area is damaged, animals slop voracious appetites; they eat huge quantities of food. But their hunger e is somewhat different from that of normal animals. Some experiments have also shown that the cessation of eating or satiety is controlled by a none called Cholecystokinin (CCK), which Is released into the blood when food reaches the intestine (Gibbs and Smith, 1973). From the above discussion, it is obvious that both hypothalamus and blood chemistry are, no doubt, responsible for hunger.

Thirst Drive

When we are deprived of water over a period of several hours, the mouth the throat become dry, which reflects dehydration of body tissues in general. So, we drink. A local stimulus theory suggests that drinking is triggered by a dry mouth. But physiologists have shown that dry mouth does not result in enough drinking to regulate the water balance of the body. Rather, thirst and drinking are controlled by processes within the body itself.

It was found that when water is placed in the stomach directly via fist short span of time elapsed before the thirst experience ceased. It is ob that the water must get into the tissues sufficiently to remove the dryness mouth and throat. Then only, the thirst is removed effectively. It has been that merely wetting the mouth temporarily removes the thirst experience.

Like hunger, some unknown conditions, aroused by a state of deficit regulate both thirst and water consumption. Of course, the important con appears to be cellular dehydration. The physiologists feel that the dryness mouth and throat is one of the factors in this regulation, but it does not explain the whole story. It is true that when the water level in the body goes down, it stimulates tiny nerve endings in the mouth and throat, and produces awareness of thirst. Again it was established that thirst couldn’t be relieved by simply taking water in the mouth, without swallowing it. So dryness of and throat is only a secondary mechanism to explain thirst drive.

Recent experiments have revealed that it is the anti-diuretic hormone seems to be the key factor in regulating the water supply to the body. The researchers feel that the thirst drive and drinking of water are mainly triggered by two mechanisms. The first one is that when the water level of the goes down, certain neurons located within the hypothalamus begins to give out water. The thirst which results from this mechanism is known as c dehydration thirst. Further experiments revealed that the loss of water the cells in the particular region of the hypothalamus might arouse the drinking behaviour. The experimenters concluded that the neurons in the preoptic of the hypothalamus known as the osmoreceptors are somehow responsible for controlling drinking behaviour of the organism.

The second mechanism which is responsible for triggering di behaviour is known as hypovolemia or the condition of low blood f volume. Studies have shown that kidneys respond to hypovolemia by for of a chemical known as angiotensin, which when released in the blood stream, triggers drinking.

It is believed that all these mechanisms work together to regulate intake of the body. The mechanisms, which explain the intake of water intake of the body. the mechanisms, which explain the intake of water, also seem to be responsible for stopping the intake of water. Others have pointed out that the role of stimuli resulting from the intake of water in stomach must have something to do with stopping of drinking. However, it can be concluded that the precise physiological mechanisms underlying the thirst drive are yet to be understood.

Sex Drive

The sex drive is considered as a powerful drive both in animals and human beings. It depends on many physiological conditions, especially in lower animals. But In case of human beings, the sex drive is very closely regulated by social restrictions. The conflict between sex motive and cultural restrictions makes sex one of the most powerful forces in influencing behaviour. Sometimes it is very difficult to classify sex purely as a biological drive. Although it is a biologically rooted drive, it differs considerably from the other two biological drives such as hunger and thirst. Sexual drive is not a response to lack of some substance in the body. It is, therefore, not triggered by homeostatic imbalance.

Physiologists are still trying to find out the exact location of the internal control of the sexual drive. They are certain that the intensity of sexual urge is dependent upon chemical substances circulating in the blood, known as sex -hormones. Studies on animals as well as human beings have clearly revealed that this urge is profoundly influenced by the presence of hormones produced by testes in males and ovaries in females. However, in case of human beings, socio-cultural and emotional factors seem to play a pivotal role.

Generally the hormones secreted by gonads, i.e., testes in males and the ovaries in females, are responsible for sexual motivation. The male sex hormones are known a testosterone. These hormones come from the testes, the ovarian hormones are known as estrogens. Experiments revealed that estrogenic hormones activate the female rats, and provide a high level of sexual motivation. In human females, the same hormones are present; but their oroduction becomes greatly accelerated at puberty.

Observation indicated that purely biological processes like hormone secretions seem to play a very minor role in the sex drive. Studies have shown hat women have greater sexual desire immediately before and after the menstrual period than during the fertile period, which corresponds to the heat period of animals. Studies with animals, as well as clinical observation on human beings have demonstrated that sexual motivation is also influence other endocrine glands, such as adrenal and pituitary glands. Of course, pituitary gland plays a key role.

In case of human beings, sexual drive is primarily stimulated by external stimuli and its expression depends upon cultural learning. Hence a psychologist has advanced a theory that sex is more a learned drive than a biological one.

Need for Sensory Stimulation

Physiologically human beings have many sensory organs, i.e. eyes, ears, skin, nose, tongue, cochlea (or labyrinthine receptor deep in the inner ears responsible for the sensation of one’s body position in the space), deep joint and muscles (kinesthetic receptors) and internal receptors, such as vise These receptors are the gateways of information about both environments and the conditions within. Studies indicate that human beings are in constant need of some kind of sensory stimulation.

Hebb and Heron (1957) conducted sensory deprivation studies and recorded its effects on college students. The students were deprived from tactual auditory and visual stimulation to a great extent and were kept in controlled sensory restrictions for a prolonged period (Zubek, 1969). It was found the subjects could not tolerate the sensory isolation for long. They experienced impairment in perceptual and intellectual functioning. Tasks which were once very simple before the onset of sensory deprivation became extremely difficult after longer periods of sensory deprivations. A great deal of emotional fluctuations such as nervousness, irritability, anger, and fear were marked in these subjects. Hallucinations also appeared in some subjects. Thus findings were that the effects of sensory deprivations are manifold Psychologists are of the view that human beings are in need of a variety of sensory stimulation in the absence of which abnormal reactions may occur

Need for Postural Changes

One of the physiological needs is to change our body-postures constantly at some intervals. Photographic evidences show that during sleep at night person changes his/her posture more than four hundred times. Although it appears apparently that one continues to sit in a single posture throughout the period in the class, there are minute shifts in his/her body position. Thus postural changes are also physiological needs.