Components Of Neuron Communication
Neurons are cells used to perceive the outside environment, the internal environment within themselves, to formulate behavioral response to those signals, and to send that information to other neurons, muscles, or glands. All information comes into a neuron through the dendrite, flows through the neuron and then leaves to go to the next neuron through the axon. Neuron communication does not rely on a single entity but entrusts several different processes that involve the contribution of neuron structure, electrical and chemical synapse, as well as neurotransmitters.
Nerve cells are the basic functioning component in the nervous system. Every part of the system is comprised of neurons that collect and distribute information to make the body function. All neurons consist of four main components; a soma, dendrites, an axon and its terminals. The soma is a cell …show more content…
body enclosing a nucleus and other organelles necessary for a functioning life, while supervising the metabolic activity of the neuron. Dendrites are branched processes that receive electrical impulses from surrounding neurons. The axon is a long projection that transmits electric signals, called action potentials, over long distances. The axon terminals are positioned at the end of the axon. These terminals are in close proximity to the dendrites of other neurons, creating synapses. Neurons use these junctions to pass messages to their target cells. These anatomical structures participate to complete the communication process.
Neurons are capable of transmitting messages via two distinct methods, chemical and electrical synapses. The electrical synapse, also known as an action potential, is involved in intracellular signaling, which is communication within a cell. Electric signals occur because electrically charged molecules, call ions, move across the membrane. These protein membranes pose as a blockade to ions. In the presence of neurotransmitters, the ions are able to travel through open ion channels. As the concentration of ions within the neuron fluctuates, so does the electrical property of the membrane itself. The polarized membrane potential at rest measures -70 milli volts. The influx and outflow of ions through the channels produces an increase in positivity within the neuron. This depolarization achieves threshold, the minimal stimulus that produces excitation, inducing a large electrical signal. The action potential travels down the length of the axon as a voltage spike. Once it reaches the terminal, it causes the stimulation of the next nerve or effecter cell.
Chemical synapses are specialized because they create a junction by which the neurons are able to signal one another, as well as other target cells, which can be found in muscles or glands.
This intercellular signaling allows neurons to form complex interconnected circuits, allowing the nervous system to moderate other systems within the body. When an action potential of a pre-synaptic neuron reaches the axon terminal, voltage-gated calcium channels are open. This allows calcium ions to enter the terminal. The calcium instigates vesicles containing neurotransmitters to bind with the cell membrane, releasing their contents into a space between the cells, called a synaptic cleft. After the neurotransmitters diffuse across the cleft, they activate receptors on the post-synaptic cell, which allow the neuron to receive the signal. In contrast to chemical synapses, the postsynaptic potential in electrical synapses is not caused by the opening of ion channels by chemical transmitters, but by direct electrical coupling of the neurons. Electrical synapses are therefore faster and more reliable than chemical
synapses.
A neurotransmitter is a specialized chemical messenger that transfers or sends information from one type of cell to another at the synapses. After release into the synaptic cleft, neurotransmitters interact with receptor proteins on the membrane of the postsynaptic cell. Each receptor is specialized to its neurotransmitter. They can be classified as excitatory or inhibitory according to their effects on postsynaptic membranes. A neurotransmitter is categorized as excitatory if activation of the receptor causes depolarization of the membrane and promotes action potential generation. When the activation of the receptor causes hyperpolarization and depresses action potential generation, it is classified as inhibitory. Different neurotransmitters have different effects on behavior and emotion. For example, impairment of the inhibitory transmitter dopamine in the brain is implicated in schizophrenia. This mental disease is classified by alterations in thinking and emotional reactions. Medications that block dopamine receptors in the brain are used to subdue symptoms. Gamma amino butyric acid is another inhibitory neurotransmitter that controls electrochemical communication among neurons. Whereas, acetylcholine, which is involved in muscular action, is an excitatory neurotransmitter found in the central and peripheral nervous systems. Scientists do not yet know exactly how many neurotransmitters exist, but more than 100 chemical messengers have been identified. Neuron communication can be found throughout the entire human body. A single neuron can attach to multiple different neurons, so when one signal is sent, it could be sent across a thousand neurons all at the same time. It is because of this that information is so quickly passed from neuron to neuron and responses can be so quick.The ability of a neuron to carry out its function of integration and propagation depends both upon its structure and its ability to generate electrical and chemical signals. While different neurons release different neurotransmitters, all neurons share the same signaling abilities
References
Cardoso, Silvia. “Communication Between Nerve Cells.” 2001 http://www.cerebromente.org.br/n12/fundamentos/neurotransmissores/neurotransmitters2.htm> Brain and Mind Fundamentals. 5 Feb 2012.
Reiscerg, Daniel. Cognition: Exploring the Science of the Mind. New York: WW Norton and Company, 2010.
Saladin, Kenneth. Anatomy and Physiology: The Unity of Form and Function 6th Edition. Boston: McGraw Hill, 2010.
Nerve cells are the basic functioning component in the nervous system. Every part of the system is comprised of neurons that collect and distribute information to make the body function. All neurons consist of four main components; a soma, dendrites, an axon and its terminals. The soma is a cell …show more content…
body enclosing a nucleus and other organelles necessary for a functioning life, while supervising the metabolic activity of the neuron. Dendrites are branched processes that receive electrical impulses from surrounding neurons. The axon is a long projection that transmits electric signals, called action potentials, over long distances. The axon terminals are positioned at the end of the axon. These terminals are in close proximity to the dendrites of other neurons, creating synapses. Neurons use these junctions to pass messages to their target cells. These anatomical structures participate to complete the communication process.
Neurons are capable of transmitting messages via two distinct methods, chemical and electrical synapses. The electrical synapse, also known as an action potential, is involved in intracellular signaling, which is communication within a cell. Electric signals occur because electrically charged molecules, call ions, move across the membrane. These protein membranes pose as a blockade to ions. In the presence of neurotransmitters, the ions are able to travel through open ion channels. As the concentration of ions within the neuron fluctuates, so does the electrical property of the membrane itself. The polarized membrane potential at rest measures -70 milli volts. The influx and outflow of ions through the channels produces an increase in positivity within the neuron. This depolarization achieves threshold, the minimal stimulus that produces excitation, inducing a large electrical signal. The action potential travels down the length of the axon as a voltage spike. Once it reaches the terminal, it causes the stimulation of the next nerve or effecter cell.
Chemical synapses are specialized because they create a junction by which the neurons are able to signal one another, as well as other target cells, which can be found in muscles or glands.
This intercellular signaling allows neurons to form complex interconnected circuits, allowing the nervous system to moderate other systems within the body. When an action potential of a pre-synaptic neuron reaches the axon terminal, voltage-gated calcium channels are open. This allows calcium ions to enter the terminal. The calcium instigates vesicles containing neurotransmitters to bind with the cell membrane, releasing their contents into a space between the cells, called a synaptic cleft. After the neurotransmitters diffuse across the cleft, they activate receptors on the post-synaptic cell, which allow the neuron to receive the signal. In contrast to chemical synapses, the postsynaptic potential in electrical synapses is not caused by the opening of ion channels by chemical transmitters, but by direct electrical coupling of the neurons. Electrical synapses are therefore faster and more reliable than chemical
synapses.
A neurotransmitter is a specialized chemical messenger that transfers or sends information from one type of cell to another at the synapses. After release into the synaptic cleft, neurotransmitters interact with receptor proteins on the membrane of the postsynaptic cell. Each receptor is specialized to its neurotransmitter. They can be classified as excitatory or inhibitory according to their effects on postsynaptic membranes. A neurotransmitter is categorized as excitatory if activation of the receptor causes depolarization of the membrane and promotes action potential generation. When the activation of the receptor causes hyperpolarization and depresses action potential generation, it is classified as inhibitory. Different neurotransmitters have different effects on behavior and emotion. For example, impairment of the inhibitory transmitter dopamine in the brain is implicated in schizophrenia. This mental disease is classified by alterations in thinking and emotional reactions. Medications that block dopamine receptors in the brain are used to subdue symptoms. Gamma amino butyric acid is another inhibitory neurotransmitter that controls electrochemical communication among neurons. Whereas, acetylcholine, which is involved in muscular action, is an excitatory neurotransmitter found in the central and peripheral nervous systems. Scientists do not yet know exactly how many neurotransmitters exist, but more than 100 chemical messengers have been identified. Neuron communication can be found throughout the entire human body. A single neuron can attach to multiple different neurons, so when one signal is sent, it could be sent across a thousand neurons all at the same time. It is because of this that information is so quickly passed from neuron to neuron and responses can be so quick.The ability of a neuron to carry out its function of integration and propagation depends both upon its structure and its ability to generate electrical and chemical signals. While different neurons release different neurotransmitters, all neurons share the same signaling abilities
References
Cardoso, Silvia. “Communication Between Nerve Cells.” 2001 http://www.cerebromente.org.br/n12/fundamentos/neurotransmissores/neurotransmitters2.htm> Brain and Mind Fundamentals. 5 Feb 2012.
Reiscerg, Daniel. Cognition: Exploring the Science of the Mind. New York: WW Norton and Company, 2010.
Saladin, Kenneth. Anatomy and Physiology: The Unity of Form and Function 6th Edition. Boston: McGraw Hill, 2010.