Calling, neuron

To understand the chemical-imbalance theory, it will be helpful to first review some basic aspects of how the brain functions. The human brain contains about ioo billion nerve cells called neurons. Each neuron is like an electrical wire with many branches. When a neuron fires, electrical impulses travel along its length from one end to the other. When an impulse reaches the end of a branch, it may stimulate the next neuron, influencing whether or not it fires. 

Each set of mathematical operations in a neural network is called a layer, and the mathematical operations in each layer are called neurons. A simple layer neural network might take an unknown spectrum and pass it through a two-layer network where the first layer, called a hidden layer, computes a basis function from the distances of the unknown to each reference signature spectrum, and the second layer, called an output layer, that combines the basis functions into a final score for the unknown sample. 

Neural networks are systems built of basic, mutually interacting elements, called neurons. The two key features of a neural network model that are of interest to us here are the properties of each neuron and the connectivity between neurons. In this section the construction of biochemical networks... 

The nervous system consists of two main units the central nervous system (CNS), which includes the brain and the spinal cord and the peripheral nervous system (PNS), which includes the body s system of nerves that control the muscles (motor function), the senses (the sensory nerves), and which are involved in other critical control functions. The individual units of the nervous system are the nerve cells, called neurons. Nenrons are a nniqne type of cell becanse they have the capacity to transmit electrical messages aronnd the body. Messages pass from one nenron to the next in a strnctnre called a synapse. Electric impnlses moving along a branch of the nenron called the axon reach the synapse (a space between nenrons) and canse the release of certain chemicals called neurotransmitters, one of which, acetylcholine, we described earlier in the chapter. These chemicals migrate to a nnit of the next nenron called the dendrites, where their presence canses the bnild-np of an electrical impnlse in the second nenron. 

The central nervous system includes the brain and the spinal cord. We shall refer to it as the CNS. The peripheral nervous system, PNS, is composed of nerves, bundles of individual cells called neurons, which connect the CNS to the rest of the body. If we make a very rough analogy to a bicycle wheel, then the CNS is the hub and the PNS is the spokes. When the bike tire hits the road, force is generated at the hub and is transmitted by the spokes. 

Artificial neural networks (ANN) are computing tools made up of simple, interconnected processing elements called neurons. The neurons are arranged in layers. The feed-forward network consists of an input layer, one or more hidden layers, and an output layer. ANNs are known to be well suited for assimilating knowledge about complex processes if they are properly subjected to input-output patterns about the process. 

MLF are composed of a number of computational elements, called neurons, generally organized in three layers (Marini, 2009). In the first one, the input layer, there are usually N neurons which correspond to the original predictor. The predictors are scaled (generally range scaled). When the number of original predictors is very high, the PCs may be used, in order to reduce the data amount and the computational time. 

Developed several decades ago, ANNs are being increasingly applied to the development and application of quantitative prediction models.43 15 ANNs simulate the parallel processing capabilities of the human brain, where a series of processing rmits (aptly called neurons ) are used to convert input variable responses into a concentration (or property) output. Neural networks cover a very wide range of techniques that are used for a wide range of applications. 

One problem with long-term inhalant abuse is that it can break down myelin in the body, according to a NIDA report. Myelin is a fatty tissue that surrounds many of the body s nerve cells called neurons. The nerve cells in the brain and spinal cord are like a command central for the body. They transmit messages that control just about everything the body does. If the myelin breaks down, the nerve cells may not be able to transmit messages. 

The brain is composed of cells called neurons. Unlike other cells in the body, neurons do not touch each other. The connection between any two neurons is made through neurotransmitters, chemicals that act as messengers. 

An artificial neural network is a parallel computational model comprised of densely interconnected adaptive processing elements called neurons or units. It is an information-processing system that has certain performance characteristics in common with the biological neural networks (Rumelhart McClelland, 1986). It resembles the... 

The brain is a complex organ responsible for the coordination and regulation of all of the activities in life. Individual cells of the brain are called neurons (Figure 4.2). Neurons communicate with one another and with the rest of the body to allow us to think, feel, and perform physical actions. Inhalants and other drugs of abuse after this basic and necessary communication between neurons to produce their effects, such as euphoria, hallucinations, and sedation. 

The basic building blocks of the nervous system are cells called neurons. Neurons are similar to other cells in the human body, such as blood cells or muscle cells, but they have the unique feature of being able to communicate with each other. The structural properties of neurons provide us with some clues to the nature of the neural transmission process. 

The brain is composed of specialized cells called neurons. Neurons transmit information by conducting electrical currents along their axons and releasing chemical substances called neurotransmitters into the synapse. Most drugs act by altering this chemical phase of neural transmission. 

A neural network consists of a number of nodes, called neurons, connected to the inputs and outputs, having the following structure for this application. 

Neural network models -- and brains -- contain sets of elements, each of which is computationally simple. The elements, called "neurons", are highly interconnected to one another in the human brain there are about 100 billion neurons, and each one is connected to about 10,000 other neurons. Neural network models often contain large numbers of simulated neurons, but not as many as are in the brain. For the remainder of this paper, we will refer to simulated neurons as "units". 

In animals the nervous and endocrine systems are primarily responsible for coordinating metabolism. The nervous system provides a rapid and efficient mechanism for acquiring and processing environmental information. Nerve cells, called neurons, release neurotransmitters (Section 14.3) at the end of long cell extensions called axons into tiny intercellular spaces called synapses. The neurotransmitter molecules bind to nearby cells, evoking specific responses from those cells. 

Neurotransmitters are chemical messengers produced by the nervous systems of higher organisms in order to relay a nerve impulse from one cell to another cell. The two cells may be nerve cells, also called neurons, or one of the cells may be a different type, such as a muscle or gland cell. A chemical messenger is necessary for rapid communication between cells if there are small gaps of 20 to 50 nanometers (7.874 X 10 -19.69 X 10 inches), called synapses or synaptic clefts, between the two cells. The two cells are referred to as either presynaptic or postsynaptic. The term presynaptic refers to the neuron that produces and releases the neurotransmitter, whereas postsynaptic refers to the cell that receives this chemical message. 

Type I NOS, also called neuronal NOS or brain constitutive NOS (bNOS), is an isozyme found in high concentrations in some neuronal cells, both in the central nervous system and peripherally (Bredt and Snyder, 1992 Nathan, 1992 Nathan and Xie, 1994). The isozyme is activated by... 

There are two nervous systems. These are the central nervous system (CNS) and the peripheral nervous system (PNS). The central nervous system consists of the brain and spinal cord, which are responsible for regulating body function. The central nervous system receives information from the peripheral nervous system, which is interpreted, and then the central nervous system sends an appropriate signal to the peripheral nervous system to stimulate cellular activity. Depending on the signal, the stimulation either increases or blocks nerve cells, which are called neurons. 

But how do regions of the healthy brain communicate Think of a hundred billion stars in the Milky Way galaxy, each firing off electrical signals. Then imagine the same number of cells—called neurons— in our brain. Each is charged with a current that pulses and flashes like an electrical storm as we think and dream and wonder. Every... 

The essence of the material that follows is the use of a multitude of elemental nonlinear computing elements (called neurons) organized as networks reminiscent of the way in which neurons are believed to be interconnected in the brain. 

A neural network is a system of interconnected processing elements called neurones or nodes. Each node has a number of inputs and one output, which is a function of the inputs. There are three types of neurone layers input, hidden, and output layers. Two layers communicate via a weight connection network. The nodes are connected together in complex systems, enabling comprehensive processing capabilities. The archetype neural network is of course the human brain, but there is no further resemblance between the brain and the mathematical algorithms of neural networks used today. 

---