Sensation And Sensitivity

Each stimulus present outside of our body emits a certain amount of physical energy that is ultimately responsible for producing some effect in one or the other sensory organs of our body. For example, is working as a stimulus for producing some effects on our sense organs. It has a particular size and shape, colour and texture and its letters reflect a particular pattern. This effect produced on our sense organs for enabling us to become aware or conscious of the nature of a particular stimulus is known as sensation and the quality or tendency of a sense organ to help us in feeling some or the other type of sensation is known as sensitivity.

We as human beings neither respond indiscriminately nor are we capable of becoming aware or conscious of each and every stimulus available in our environment. We do not have the same power of smelling as our dog has. We can't see in the dark but our cat is capable of doing so. Similarly the light or sound waves that are beyond our sensation can be successfully caught by our television set. Not only in terms of detection but also in terms of discrimination we have our limitations. The degree to which we are capable of detecting a stimulus or discriminating between two or more stimuli for finding out the difference, we are said to be sensitive or are attributed to possess sensitivity to that stimulus or that difference.

Senses

Human senses are in fact the windows to the world - internal as well as external.These are the gateways of all information that our brain receives by interacting with the stimuli present inside and outside of our body. Our great ancient thinkers held that there were five human senses - Vision , Hearing , Taste , and Touch corresponding to the sense organs , Eyes , Ears , Nose , Tongue , and Skin of our body. During the subsequent ages there has been an addition of some more senses to this list.


These senses may be grouped into five categories as under:

Visual Senses - Sense of vision.
Auditory Senses - Sense of hearing.
Chemical Senses - Sense of small ans sense of taste.
Skin Senses - Sense of pressure , sense of temperature and pain.
Body Senses - Kinesthetic sense and Vestibular sense.

Understanding Instincts

From time immemorial , the term instinct has been used for an innate disposition or characteristic that makes an organism to respond or to act in such a way that helps him in his adjustment or adaptation including the survival of his species. Consequently instinctive behaviour has been understood as an unlearned species.

During the nineteenth century when Charles Darwin presented his theory that humans are linked to other species , it was also concluded that like their relatives , the behaviour of human beings is motivated by instincts. Inspired by the views of Charles Darwin in 1890 , William James , a Harvard psychologist tried to provide a long list of the human instincts and defined the term instincts in the following way:

"Instinct is usually defined as the faculty of acting in such a way as to produce certain ends , without foresight of the ends , and without previous education in the performance . "

(James , 1969)

Personality Meaning and Nature

The Term "personality" stems from the Latin word persona,which was the name given to the masks actors wore and the characters they portrayed.The meaning of the word personality in practice has changed little since classical time for it is still quite common to hear the comments such as "I do not know what he sees in her,she has a very poor personality ".

A Personality is a thing or quality that is possessed by all of us and we can paste such labels as fine,good or poor on it on the basis of the physical markup,manner of their walking,talking,dressing and a host of other similar characteristics processed by individuals.

Watson the father of behaviorism,taking clues from his behavioral studies,to conclude that "Personality is the sum of activities that can be dis covered by actual observations aver a long enough period of time to give information".(1930)

Morton Prince said to "Personality is the sum total of all the biological innate dispositions,in pulses,tendencies.appetites and instincts of the individual and the dispositions and tendencies acquired by experience".(1929)

Cattell remarked: "Personality is that which permits a prediction of what a person will do in a given situation".(1970)

Eysenck said to,"Personality is the more or less stable and enduring organisation of a person's character temperament,intellect and physique which determine his unique adjustment to the environment". (1971)

Twins Mechanism

Life is the result of the union of two cells-male and female.In a normal case when a single ovum is fertilized by sperm cell of the male,it results in the birth of a single offspring.However,in some eases,this normal function is distributed and there are cases of multiple births.The birth two or more offsprings at a time.The birth of distinct types of twins namely identical twins and fraternal twins.

Identical Twins

In the process of the fertilization of the ovum by the sperm,the ovum is made to spilt into two parts.In a normal process these parts are again united.Sometimes,however it so happens that these two spilt parts fail to unite together.The results in that each part is developed into a complete individual in the form of the pair of the identical twins.

The twins produced,are thus termed identical on account of the identical nature of the genetic material.They are found to process almost the same somatic structure and characterstics and are definitely of the same sex.

Fraternal Twins

Normally in each menstrual cycle the female ovaries produce a single ovum that can be fertilized by a spam cell.In an exceptional case,two ova may be produced simultaneously and be fertilized at the same time by two different sperms.It may then result in the conception of two individuals who may be grown simultanesouly in the womb of the mother.These individuals are known as ferternal twins.

Determination of Sex

The First twenty-two pairs of chromosomes are called autosomes.These chromosomes determine the development of most of our body structures and characteristics.The remaining twenty-third pair consists of the sex chromosomes.These sex chromosomes decide the individuals sex and other sex-linked characteristics.

They are two different types of sex chromosomes X Chromosome (usually this is big size) and Y chromosome(smaller than X).In the male child one member of the sex chromosome is X chromosome (contributed by mother).In the female child both of these sex chromosomes,one from each parent,are X chromosomes.

All Eggs have X chromosomes,but sperm cells may contain either type,Therefore,the mother's role in the determination of sex is quite natural.At this time of conception she can contribute only one type of sex chromosome (i.e) X chromosome.Much depends upon the possibility of the type of sex chromosomes X (or) Y that may be transmitted by the sperm cell of the father.

If X chromosome is transmitted the child will be female and if Y chromosome is transmitted it will result in a male child.In this way,it is not the mother but the father who is biologically more countable for determination of the sex of the child.

Heredity

Heredity refers to a Biological Mechanism as a result of which a child obtains something in terms of specific species (or) Ancestral characterstics by which he can trace his individuality from his ancestral stock through his parents.

Heredity,thus contributes in the form of inheritance just as we inherit land,money and other assets (or) liabilities from our parents and forefathers.Now the question may arise,when does a child inherit the specific ancestral characterstics.

Human Life thus starts from a single cell produced by the union of germ cells,one form each parent and gradually develops into a complicated composition of trillions of body cells and yet containig the same genetic material as was inherited at the time of conception.

The Zygote (i.e) fertilized ovum consists of a semi-fluid mass called Cytop lasm and within the cytoplasm there is a nucleus which contains the chromosomes.Chromosomes always exist in pairs.In human zygote there are 23 pairs of chromosomes (46 Individual Chromosomes),23 pairs of which are contributed by the father and 23 by the mother and this is why for the transmission of herditary characterstics both mother and father are said to be equal partners.

Chromosomes possess a thread like structure and are made up very small units called "Genes".It is estimated that there are more than 1000 genes in each human chromosome cell.Consequently the possibility regarding the combination of 30,000 characterstics each mother and father,may help us to understand well the uni-genes of each individual.

PsychoPhysical Methods

The Branch of Psychology which is concerned with the study of relationship between physical and psychological phenomenon is called Psycho-Physics.The Term Psycho-Physical method may be referred to all those methods in which attempts are made to employ physical devices for the scientific measurement of some psychological experiences like sensation of weight,brightness,loudness and others.

Psycho-logical Phenomena like sleep or span of memory ,can also be studied through the use of such psycho-physical methods.Three Classical psycho physical methods devised by the German physiologist and physicist Gustav Fechner (1801-1887).They are

1.The Method of minimal changes (or) methods of limits.
2.The Method of constant stimuli (or) the method of right and wrong responses.
3.The Method of average (or) mean error.

Method of Minimal Changes

The subject is exposed to experience a sensation.For Example,He may be asked whether he is able to see the object lying at a particular distance or not.If he says no then the value of the distance is gradually decreased until the subject reports that he is able to see it.In the next round,The object may be placed at the distance much nearer than the absolute threshold say 70cms in the present case.

All these values pertaining to minimal changes in the value of the absolute threshold (or) difference threshold in both decending and ascending series.

The Method of Constant Stimuli

In this method the value of the intensity of the sensory stimulus is neither gradually increased nor decreased in the case of the method of limits but the sensory stimuli of varying intensity are presented at random before the subject.

The Method of Average Error

This method is also called the method of mean error or the adjustment method.In performing experiment by this method,the subject is presented with some stimulus of the standard intensity.The avereage of the standard value for giving the subject's absolute threshold of sensitivity to the stimulus.

Methods Of Psychology

Experimental psychology

Experimental psychology approaches psychology as one of the natural sciences, and therefore assumes that it is susceptible to the experimental method. Many experimental psychologists have gone further, and have assumed that all methods of investigation other than experimentation are suspect. In particular, experimental psychologists have been inclined to discount the case study and interview methods as they have been used in clinical and developmental psychology.


Ibn al-Haytham is considered by some to have been a forerunner of experimental psychology, for his experimental approach to the psychology of visual perception and optical illusions in his Book of Optics.A Persian psychologist who discovered the concept of reaction time.Further progress was not made until the 19Th century when Wilhelm Wundt, considered the father of experimental psychology, founded experimental psychology as a discipline and introduced a mathematical and quantitative approach to experimental psychology. Other early experimental psychologists, including Hermann Ebbinghaus and Edward Titchener, included introspection among their experimental methods.

However, in the first half of the twentieth century, experimental psychology became closely allied with behaviourism, especially in the United States, and this led to some neglect of mental phenomena.

Introspection

Introspection is the mental self-observation reporting of conscious inner thoughts, desires and sensations. It is a conscious mental and usually purposive process relying on thinking, reasoning, and examining one's own thoughts feelings, and, in more spiritual cases, one's soul. It can also be called contemplation of one's self, and is contrasted with Extro spection, the observation of things external to one's self.


Introspection may be used synonymously with self-reflection and used in a similar way. Cognitive psychology accepts the use of the scientific method, but rejects introspection as a valid method of investigation for this reason. It should be noted that Herbert Simon and Allen Ne well identified the 'thinking-aloud' protocol, in which investigators view a subject engaged in introspection, and who speaks his thoughts aloud, thus allowing study of his introspection.

ARTICLE SOURCE: http://en.wikipedia.org/wiki/Experimental
http://en.wikipedia.org/wiki/Introspection

Types Of Psychology

Psychology encompasses a vast domain, and includes many different approaches to the study of mental processes and behavior. Below are the major areas of inquiry that comprise psychology, divided into fields of research psychology and fields of applied psychology. A comprehensive list of the sub-fields and areas within psychology can be found at the Types of psychology.

Abnormal psychology

Abnormal psychology is the study of abnormal behavior in order to describe, predict, explain, and change abnormal patterns of functioning. Abnormal psychology studies the nature of psychopathology and its causes, and this knowledge is applied in clinical psychology to treat a patient with psychological disorders.

Biological psychology

Biological psychology is the scientific study of the biological bases of behavior and mental states. Because all behavior is controlled by the central nervous system, it is sensible to study how the brain functions in order to understand behavior.The approach of cognitive neuroscience to studying the link between brain and behavior is to use neuroimaging tools, such as to observe which areas of the brain are active during a particular task.

Cognitive psychology

Cognitive psychology is associated with a school of thought known as cognitives, whose adherents argue for an information processing model of mental function, informed by positivism and experimental psychology.Cognitive science is a conjoined enterprise of cognitive psychologists, neurobiology, workers in artificial intelligence, logicians, linguists, and social scientists.


Educational psychology

Educational psychology is the study of how humans learn in educational settings, the effectiveness of educational interventions, the psychology of teaching, and the social psychology of schools as organizations.

Developmental psychology

Mainly focusing on the development of the human mind through the life span, developmental psychology seeks to understand how people come to perceive, understand, and act within the world and how these processes change as they age.

Social psychology

Social psychology is the study of the nature and causes of human social behavior and mental processes, with an emphasis on how people think towards each other and how they relate to each other. Social Psychology aims to understand how we make sense of social situations.

Clinical psychology

Clinical psychology includes the study and application of psychology for the purpose of understanding, preventing, and relieving psychologically-based distress or dysfunction and to promote subjective well-being and personal development. Central to its practice are psychological assessment and psychotherapy, although clinical psychologists may also engage in research, teaching, consultation, forensic testimony, and program development and administration.

ARTICLE SOURCE: http://en.wikipedia.org/wiki/Psychology

Sigmund Freud Psychoanalysis

In 1890s, The Austrian physician Sigmund Freud developed a method of psychotherapy known as psychoanalysis. Freud's understanding of the mind was largely based on interpretive methods, introspection and clinical observations, and was focused in particular on resolving unconscious conflict, mental distress and psychopathology.

Freud also had a significant influence on Carl Jung, whose analytical psychology became an alternative form of depth psychology. Philosopher Karl Popper argued that Freud's psychoanalytic theories were presented in untestable form.

Freud's theories became very well-known, largely because they tackled subjects such as sexuality, repression, and the unconscious mind as general aspects of psychological development. These were largely considered taboo subjects at the time, and Freud provided a catalyst for them to be openly discussed in polite society.

Due to their subjective nature, Freud's theories are often of limited interest to many scientifically oriented psychology departments. Followers of Freud who accept the basic ideas of psychoanalysis but alter it in some way are called neo-Freudians. Modification of Jung's theories has led to the archetypal and process-oriented schools of psychological thought.

Behaviorism:

Partly in opposition to the subjective and introspective nature of Freudian psycho dynamics, and its focus on the recollection of childhood experiences, during the early decades of the 20th century, behaviorism gained popularity as a guiding psychological theory. Founded by John B. Watson and embraced and extended by Edward Thorndike, Clark L. Hull, Edward C. Tolman, and later B.F. Skinner, behaviorism was grounded in animal experimentation in the laboratory. Behaviorism was the dominant paradigm in American psychology throughout the first half of the 20th century. However, the modern field of psychology is largely dominated by cognitive psychology.

ARTICLE SOURCE: http://en.wikipedia.org/wiki/Sigmund_Freud

A Study Of Human Psychology

A Study of human behavior is a Psychology.Psychology is an academic and applied discipline involving the phenomenological and scientific study of mental processes and behavior. Psychologists study such concepts as perception, cognition, emotion, personality, behavior, interpersonal relationships, and the individual and collective unconscious.

Psychology includes many sub-fields of study and application concerned with such areas as human development, sports, health, industry, media, law. Psychology also refers to the application of such knowledge to various spheres of human activity including issues related to daily life e.g. family, education, and work and the treatment of mental health problems.

The study of psychology in a philosophical context dates back to the ancient civilizations of Egypt, Greece, China and India. Psychology began adopting a more clinical and experimental approach under medieval Muslim psychologists and physicians, who built psychiatric hospitals for such purposes.

ARTICLE SOURCE: http://en.wikipedia.org/wiki/Psychology