Function of neuron

                          

Communication within neuron: The neuron receives the information from anon of other neuron or through sense organs. When neuron is at rest, there is tiny negative electrical charge (-70 millivolt) across the cell membrane. This electrical charge is produced because several negative charge ions (like cl, protein molecules) and positive charge ions exist in different concentration inside and outside the membrane. As the concentration of negatively charged ions is much than the positive charge ions inside of the cell membrane, the charge inside the membrane is slightly negative compared to the outside of he cell membrane. The electrical potential develop when neuron is at rest is called the resting potential. When neuron is stimulated either by chemical message from other neurons or directly by heat, light pressure etc. it produces a type of single called graded potential (that results from the simulation of dendrite or cell body). Strength of the graded potential varies with the intensity of the stimulus and cause local flow of current which decrease with distance from the stimulus point. It can cause either a depolarization (an excitatory response that may lead to and action potential) or hyper polarization (an inhibitory response which makes it harder for an action potential to occur) depending on the ion let in(or out). The incoming information is conveyed over short distances usually up to cell body. If it caused depolarization or if the magnitude of incoming information exceeds the threshold, action potentials generated. Action potential is a rapidly moving wave of depolarization that travels along the cell membrane of a neuron (Baron, 2003). Action potential is an “all or no” phenomena. During action potential, the sodium ions are briefly allowed to enter inside the cell membrane and negative charge ions are allowed to pass outside the membrane. The influx of sodium ion rapidly moves through out the length of the axon, thus transmitting the incoming information to the terminal branches. The neuron then actively pumps the sodium ion outside the membrane, thus regaining its resting potential. At this phase neuron does not receive any other information. This phase is called refractory phase. In this way information is communicated within the neuron.

Types of Neuron:

                 

Neurons can be classified in different way. We can classify neuron as unipolar, bipolar and multipolar. We can also divide them as Myelinated. Another classification of neuron is sensory, motor and interneuron. We will discuss this classification here. This classification divides neuron into different type according to the function they carry out.

A.  Sensory Neuron: Sensory neurons, also knowh as afferent neurons, are the types of neuron wich carry out the information from different parts of body to brain and spinal cord. These neurons lie in peripheral nervoussystem and carry message from special receptors in skin, muscles and other internal and external sense organs to the spinal cord which sends them along to the brain. They evoke sensations of touch, pain, heat, cold, vision, hearing and taste.

B.   Motor Neurons: Motor neurons (motion producing), also known as efferent neurons, are the type of neurons that carry oders from the central nervous system to muscles, glands and internal organs. They enable us to move our bodies and cause glands to contract and secret various substances. Most motor neurons are stimulated by interneurons although some are stimulated directly by sensory neurons. These neurons are responsible for all motor activities.

C.   Interneurons: Interneurons, also known as association neurons are the neurons that connect various neurons. These neurons are found in brain and spinal cord and represent the majority of neurons in our brain. They are stimulated by signals reaching them from sensory neurons, other interneurons and both. It is estimated that the human brain contains 100 billion interneurons averaging 1000 synapses on each.

Neuron

   

                            

Neuron is the structural and functional unit of nervous system that processes and transmits information of nervous system. The peculiar property of an neuron is that it cannot be replaced once destroyed because neurons do not go through mitosis (A process of cell division)neurons conduct the information in the form of electrical impulses from one part of the body to another. For example, if you touch a candle flame for more than an instant, pain nerves (receptors) in your finger send a message up through your hand and arm to the spinal cord and the brain. The brain records PAIN and sends message back down to various parts of the body. The mouth cries, “Ouch!” the arm, hand and body jerk away from he flame, and the finger hurts. This all happens in milliseconds. Much of the brain is made highly specialized neurons. They interact to control he different senses, thought, mood and motion. Neurons exist in a number of different shapes and sizes and can be classified by their morphology and function (Neuron, Retrieved on March 11 2010.).The number of neurons in a human nervous system has been estimated at 100 to200 billion (Mangal, 2006).

Biological Basis of behavior

            

Behavior of and individual is guided mainly by biological, psychological and socio-cultural factors. Biological factors included hereditary, role of nervous system, neurotransmitters and different hormones secreted by glands. These biological factors are very important in determining behaviors. Some examples of he biological factors which contribute for our behavior are illustrated here. The Hippocampus and the amygdale are involved in formation of new memories, the retention of memories and emotions (witting, 2001). Vasopressin hormone is an important regulator of water balance in the body (Levinthal, 2003)imbalance in the neurotransmitters dopamine and serotonin may underlie mental disturbances like schizophrenia and depression (Wade and tarvis, 1990).

Nervous system is the sum totals of the tissues that record and distribute information within individual. It is the complex network of neurons that regulates bodily processes and is ultimately responsible for all aspects of conscious experience. Nervous system is composed mainly of two types of cells i.e. Neuron and Glia cell. “Glia Cell provide a mechanical framework supporting the network of neurons, they insulate one neuron from another hey police the nervous system from foreign materials and debris resulting from injury or infection and hey  provide chemical barrier, the blood brain barrier which prevents some substances in the blood from contacting the sensitive nerve cells” (Mohanty, 1990). Neuron is the structural and functional unit of nervous system. All the function of nervous system is carried oft through neurons.

Relationship between sociology, anthropology and psychology

Psychology, sociology and anthropology are complementary disciplines. Sociology is the study of organization, development and institution of human society. It studies the principles underlying the formation, growth and functioning of different kinds of groups. Psychology also studies groups. However, for psychology focus of study becomes individual in group. Psychology borrows finding of sociology in studying the role of culture in group dynamic and behavior. Let us take an example of antisocial gang to illustrate the relationship between sociology and psychology. Both sociologists and psychologists are interested in studying the antisocial gang. The focus of sociology becomes the social and economic causes of gang, the relation of gang with law and order etc. However, the focus of psychologists may be on understanding the individual nature in gang, causes of gang behavior and impact of gang behavior on particular culture.

Anthropology is the study of the physical, social, and cultural origins and development of the human race. It mostly deals with primitive and tribal people. It is particularly concerned with the culture, tradition, manners, customs, and rituals of such people. Psychology draws relevant data from anthropology regarding the evolution of particular group of people. Anthropologists take information about abnormality and nature of human beings through the studies of psychology. Psychology is however, not only concerned with study of tribal people.

The most obvious relation among these three disciplines is that all of these disciplines are concerned with study of behavior. Integral information gained through these three disciplines gives complete picture about human beings and their behavior.

Applied scope:

Applied field of psychology is mainly concerned with applying psychology to tackle practical problems. It uses various theories, principle and knowledge gained through research to tackle such problems. The are of applied psychology may be resolving exam anxiety, developing communicating skills in individual, treating mentally ill people etc. in recent years applies area of psychology has broadened to a large extent. There are many branches of applied psychology that help people in various ways. Some of the major areas of applied psychology are:

1. Clinical psychology

2. Counseling psychology

3. Health psychology

4. Organizational psychology

5. Educationl psychology

6. Consumer psychology