A Literature Review On Biological Neural Network

1.An extensive network of specialized cells that carry information to and from all parts of the body is called the nervous system.

The proper functioning of the cells allow us to act, think, learn, remember and control complex behaviors. In order to understand how the brain performs these essential functions we must first understand the different components of the cells; such as the function of neurons and their supporting cells in the nervous system. The communication from neuron to neuron, the processes involved in the production of an action potential, how an action potential is conducted along a myelinated axon; and the process of synaptic transmission will be discussed and examined.

from figure 3 that input is feeding to the network in different time steps, not at once like feed forward case. However the parameters the network learns throughout different

The way we think, process, and function is conducted through our nervous system. It is composed of nerve cells called neurons. The brain has 100 billion neurons. They receive an electrical impulse that excites one neuron cell and starts a chain reaction from one to the next and initiates an action. A neuron is composed of a cell body, and has dendrites and an axon. Dendrites are thin tendrils that stretch from the neuron to receive the electrical signal. It passes then on through the cell body to the axon, a long thin strand, that passes it on to the next neuron. Neurons do not touch each other. The junction between neurons is called a synapse. They pass on messages through chemicals called neurotransmitters that jump from the axon and bind to a receptor site on the next neuron’s dendrites across a gap called the synaptic cleft.

Cnidarians do not have a central nervous system (no local concentration of nerve cells, no brain), but the anemones simple differentiated nervous system works much the same. Arrangements of nerve cells within a loose network called nerve nets process and respond to stimuli much like a brain would. For example, in response to stimuli, nerve cells emit electrical impulses through the nerve net to all parts of the anemone’s body, causing contractions in the anemone’s muscles. The result is movement.

The cell body is the roughly round part of a neuron that contains the nucleus, mitochondria, and most of the cellular organelles. There are 3 basic classes of neurons: afferent neurons, efferent neurons, and interneurons. Afferent neurons. Also known as sensory neurons, afferent neurons transmit sensory signals to the central nervous system from receptors in the body.Efferent neurons. Also known as motor neurons, efferent neurons transmit signals from the central nervous system to effectors in the body such as muscles and glands.Interneurons. Interneurons form complex networks within the central nervous system to integrate the information received from afferent neurons and to direct the function of the body through efferent

Biometrics is a term that refers to the broad amassment of various human characteristics. In computer science, biometrics authentication is used for access and a form of identification. Biometrics can also be used to survey and identify individuals in groups. Statistically, biometrics are unique and measurable to only one individual. When biometrics are used in authentication they can be broken down into two groups of measurability, physiological characteristics and behavioral characteristics. Physiological characteristic can be, but are not limited to, Biometrics that consist of a person’s Deoxyribonucleic acid (DNA), fingerprints, face, hands, eyes, ears or even odor. The second of the two characteristics, are the behavioral

The Nervous System is a complex system comprised of two parts: The Central Nervous System and the Peripheral Nervous System. Each system is then comprised of nerves and specialized cells, called neurons. The function of a neuron is to transmit messages throughout the body. The brain has approximately 100 billion neurons, ranging in many different sizes and shapes. Neurons are classified as cells because they have a cell membrane, nucleus, cytoplasm, and mitochondria, as well as carry out many of the same processes as a cell (i.e protein synthesis). But, a neuron is unlike a cell in that they have special structures such as dendrites and axons, communicate through electrochemical processes, and contain special chemicals called neurotransmitters (instead of hormones).

An analog or analogue signal is any continuous signal for which the time varying feature (variable) of the signal is a representation of some other time varying quantity, i.e., analog to another time varying signal. For example, in an analog audio signal, the instantaneous voltage of the signal varies continuously with the pressure of the sound waves. It differs from a digital signal, in which a continuous quantity is represented by a discrete function which can only take on one of a finite number of values. The term analog signal usually refers to electrical signals; however, mechanical, hydraulic, and other systems may also convey analog signals.

You have seen biometric technology in the films Mission: Impossible and Gattaca. The technology has also graced the covers of many weekly news magazines. But many people, even though the technology has been widely talked about for the last half decade, are still surprisingly unaware of what biometrics are and why the technology is so important for computer security and personal identification.

Biometric technologies are getting better and finely tuned. The rate of false readings and errors has sharply fallen. However it still requires careful consideration and planning to implement a biometric identification system. They are most costly and complicated to implement as compared with other authentication systems. A proper evaluation of the system is important before purchasing any biometric system. A thorough risk analysis is necessary. In many cases biometrics may be overkill. Biometrics must be used if there is high level of risk involved. Customer acceptance is also important when logging on to company websites. Home users might not be ready to install biometrics on home computers for online banking.

Biometric technique is now becoming the foundation of a wide array of highly secure identification and personal verification. Recently world events have took place which leads to an increase the interest in security that will impel biometrics into majority use.

The neural network is a powerful mathematical method that is capable of representing complex non-linear functions cite{RLStateOfArt_ch10} which has been used widely in machine learning applications. Figure

1. Direct: This means that the model output increases on increasing the value of input signal and decreases on decreasing the value.

Then, we have the Cell body (or Soma), which contains the nucleus, which in return contains the DNA(deoxyribonucleic acid) of the cell and controls the development of the nerve cells, and the structure of the cell body, is where lots of data information is being processed. Examining the lower part of a neuron’s structure, we have the Axons which are long distensions where signals travel all the way to the Axon terminal, and these last ones connect themselves to other neurons by realising neurotransmitters across the synapse as a consequence, these last ones are what influence the activity of other cells.