Basic Physiology of a Neuron and How it Fires
Describe the basic physiology of a neuron. Detail the manner by which neurons fire action potentials and how neurons communicate with one another across synapses. Outline the process of how an action petential occurs and hoe it propagates down an axon. Explain how chemical transmission occurs at synapses and how this allows neurons to activate of inhibit one another.
[Picture from "Answer to Neuron Structure"]
Neurons are the basic units of the brain. Above is a picture of a prototypical neuron with its parts labeled by number. The objects labeled by the number one are Dendrites. Dendrites conduct nerve impulses towards the nerve cell. The nucleus, which regulates activities in the cell is labelled 2. Labeled 3, the soma or cell body, is the body of the neuron. The myelinated sheath, of the structure labeled 4, acts like an insulator. Not all neurons have myelinated sheaths. In the types that do, messages to said to 'jump' along the axon. Structure 6 is the axon, which conducts impulses away from the cell body. Finally, structures labeled 8 are called terminal branches or synaptic terminals. These transfer impulses toward the next neuron. (Answer to Neuron Structure)
Action potential is what allows for nerve impulses. The process of action potential begins when there is a difference in concentration of ions outside and inside of the neuron. Before this process begins, the neurons are in a state called resting potential. In this state, neurons are negativelty charged at -70 mv. If an electrical stimulus is applied, sodium dependent gates open and positive sodium ions to rush in. Now the neuron is positively charged. The added sodium creates what is known as a 'spi...
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...complete description is the algorithmic level. For a Turing machine an algorithmic description would a table of instructions detailing what to do if a certain situation occurs and what steps to follow. Finally, the computational description of a turing machine would be depend on the exact function that was being carried out. A set example can't be given becuase a turing machine is a hypothetical machine.
Each of these levels of the tri-level hypothesis contains limitations. The limitations of the implementational level is that one can't be sure where part of the machine is necessary for it to function. Limitations on the algorithmic level occur because a formal account of information and the manner of its manipulation cannot describe the task very well. Limitations occur at the computational level because one needs the lower two levels to fully explain a process.
In the beginning phases of muscle contraction, a “cocked” motor neuron in the spinal cord is activated to form a neuromuscular junction with each muscle fiber when it begins branching out to each cell. An action potential is passed down the nerve, releasing calcium, which simultaneously stimulates the release of acetylcholine onto the sarcolemma. As long as calcium and ATP are present, the contraction will continue. Acetylcholine then initiates the resting potential’s change under the motor end plate, stimulates the action potential, and passes along both directions on the surface of the muscle fiber. Sodium ions rush into the cell through the open channels to depolarize the sarcolemma. The depolarization spreads. The potassium channels open while the sodium channels close off, which repolarizes the entire cell. The action potential is dispersed throughout the cell through the transverse tubule, causing the sarcoplasmic reticulum to release
The brain is an organ that regulates body functions, behaviors, and emotions. Neurons are the cells that fulfill these functions. How do neurons do this? A neuron plays an important role in the central nervous system. Why? Because neurons regulate how we think, feel, and control our body functions. A typical neuron has three parts: cell body, axon, and dendrites. When a neuron receives an electrical impulse, that impulse travels
In this paper I will evaluate and present A.M. Turing’s test for machine intelligence and describe how the test works. I will explain how the Turing test is a good way to answer if machines can think. I will also discuss Objection (4) the argument from Consciousness and Objection (6) Lady Lovelace’s Objection and how Turing responded to both of the objections. And lastly, I will give my opinion on about the Turing test and if the test is a good way to answer if a machine can think.
The brain is part of the central nervous system, which consists of neurons and glia. Neurons which are the excitable nerve cells of the nervous system that conduct electrical impulses, or signals, that serve as communication between the brain, sensory receptors, muscles, and spinal cord. In order to achieve rapid communication over a long distance, neurons have developed a special ability for sending electrical signals, called action potentials, along axons. The way in which the cell body of a neuron communicates with its own terminals via the axon is called conduction. In order for conduction to occur, an action potential which is an electrical signal that occurs in a neuron due to ions moving across the neuronal membrane which results in depolarization of a neuron, is to be generated near the cell body area of the axon. Wh...
When a message comes to the brain from body parts such as the hand, the brain dictates the body on how to respond such as instructing muscles in the hand to pull away from a hot stove. The nerves in one’s skin send a message of pain to the brain. In response, the brain sends a message back dictating the muscles in one’s hand to pull away from the source of pain. Sensory neurons are nerve cells that carry signals from outside of the body to the central nervous system. Neurons form nerve fibers that transmit impulses throughout the body. Neurons consists of three basic parts: the cell body, axon, and dendrites. The axon carries the nerve impulse along the cell. Sensory and motor neurons are insulated by a layer of myelin sheath, the myelin helps
The neurons or brain cells are shaped like trees. Young brain cells, called soma, resemble an acorn or small seed of a tree. The seed sprouts limbs when stimulated, called dendrites. Further on in development, the cell will grow a trunk like structure called an axon. The axon has an outer shell, like the bark of a tree, called the myelin sheath. Finally, at the base of the cell, there are root-like structures called axon terminal bulbs. Through these bulbs and the dendrite of another cell, cells communicate with each other through electrochemical impulses. These impulses cause the dendrites to
Neurons are the cells that create brain activity, passing chemical and electric signals from on...
Turing earned a fellowship at King’s college and the following year the Smith’s Prize for his work in probability theory. Afterward, he chose a path away from pure math into mathematical logic and began to work on solving the Entscheidungsproblem, a problem in decidability. This was an attempt to prove that there was a method by which any given mathematical assertion was provable. As he began to dive in to this he worked on first defining what a method was. In doing so he began what today is called the Turing Machine. The Turing Machine is a three-fold inspiration composed of logical instructions, the action of the mind, and a machine which can in principle be embodied in a practical physical form. It is the application of an algorithm embodied in a finite state machine.
In this essay, I describe in detail a hypothetical test contemporarily known as the Turing test along with it’s respective objective. In addition, I examine a distinguished objection to the test, and Turing’s consequential response to it.
In their inactive state neurons have a negative potential, called the resting membrane potential. Action potentials changes the transmembrane potential from negative to positive. Action potentials are carried along axons, and are the basis for "information transportation" from one cell in the nervous system to another. Other types of electrical signals are possible, but we'll focus on action potentials. These electrical signals arise from ion fluxes produced by nerve cell membranes that are selectively permeable to different ions.
The neuron plays an important role in the occupation of the brain (Rollin Koscis). A neuron is...
Russell’s Theory of Definite Description has totally changed the way we view definite descriptions by solving the three logical paradoxes. It is undeniable that the theory itself is not yet perfect and there can be objections on this theory. Still, until now, Russell’s theory is the most logical explanation of definite description’s role.
Although the majority of people cannot imagine life without computers, they owe their gratitude toward an algorithm machine developed seventy to eighty years ago. Although the enormous size and primitive form of the object might appear completely unrelated to modern technology, its importance cannot be over-stated. Not only did the Turing Machine help the Allies win World War II, but it also laid the foundation for all computers that are in use today. The machine also helped its creator, Alan Turing, to design more advanced devices that still cause discussion and controversy today. The Turing Machine serves as a testament to the ingenuity of its creator, the potential of technology, and the glory of innovation.
The brain consists of both neurons and glia cells. The neurons, which are cells housed in a cell body called a Soma, have branches which extend from them, referred to as dendrites. From these dendrites extend axons which send and receive impulses, ending at junction points called synapses. It is at these synapse points that the transfer of information takes place.
Both the CNS and PNS communicate via neurons. Neurons are nerve cells that consist of den...