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nervous_system_and_neurons [2022/12/29 06:49] – andrewtaustinnervous_system_and_neurons [2024/04/10 13:41] (current) – [Neurons in the brain] andrewtaustin
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 +{{tag>Anatomy}} 
 =======Overview the nervous system======= =======Overview the nervous system=======
  
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 The nervous system is mainly made up of cells called neurons. These are responsible for carrying messages to and from different parts of the body. Neurons are connected to each other, and to other cells, by synapses, which carry electrical signals, and neurotransmitters, which are the body’s chemical messengers. (https://www.healthdirect.gov.au/nervous-system) The nervous system is mainly made up of cells called neurons. These are responsible for carrying messages to and from different parts of the body. Neurons are connected to each other, and to other cells, by synapses, which carry electrical signals, and neurotransmitters, which are the body’s chemical messengers. (https://www.healthdirect.gov.au/nervous-system)
  
-{{:brain1.png?400|}}+{{:brain1.png?800|}} 
 + 
  
 =====The Central Nervous system (CNS)=====  =====The Central Nervous system (CNS)===== 
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 The brain and spinal cord are protected from damage by a clear liquid called cerebrospinal fluid, 3 layers of membranes called the meninges, and the hard bones of the skull and backbone. The brain and spinal cord are protected from damage by a clear liquid called cerebrospinal fluid, 3 layers of membranes called the meninges, and the hard bones of the skull and backbone.
    
 +
 +{{:neuron.png?400|}}
 =====NEURONS=====  =====NEURONS===== 
  
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 There are different types of neurons, both in the brain and the spinal cord. They are generally divided according to where they orginate, where they project to and which neurotransmitters they use. There are different types of neurons, both in the brain and the spinal cord. They are generally divided according to where they orginate, where they project to and which neurotransmitters they use.
  
 +
 +{{:types_of_neurons.jpg?400|}}
 Neurons are the cells that make up the brain and the nervous system. They are the fundamental units that send and receive signals which allow us to move our muscles, feel the external world, think, form memories and much more. Neurons are the cells that make up the brain and the nervous system. They are the fundamental units that send and receive signals which allow us to move our muscles, feel the external world, think, form memories and much more.
 Just from looking down a microscope, however, it becomes very clear that not all neurons are the same. So just how many types of neurons are there? And how do scientists decide on the categories? For neurons in the brain, at least, this isn’t an easy question to answer. For the spinal cord though, we can say that there are three types of neurons: sensory, motor, and interneurons. Just from looking down a microscope, however, it becomes very clear that not all neurons are the same. So just how many types of neurons are there? And how do scientists decide on the categories? For neurons in the brain, at least, this isn’t an easy question to answer. For the spinal cord though, we can say that there are three types of neurons: sensory, motor, and interneurons.
  
-=====Sensory neurons======+ 
 + 
 +===Sensory neurons===
  
 Sensory neurons are the nerve cells that are activated by sensory input from the environment - for example, when you touch a hot surface with your fingertips, the sensory neurons will be the ones firing and sending off signals to the rest of the nervous system about the information they have received. Sensory neurons are the nerve cells that are activated by sensory input from the environment - for example, when you touch a hot surface with your fingertips, the sensory neurons will be the ones firing and sending off signals to the rest of the nervous system about the information they have received.
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 However, within any of these sensory or motor regions, there are tens or even hundreds of different types of neurons. In fact, researchers are still trying to devise a way to neatly classify the huge variety of neurons that exist in the brain. However, within any of these sensory or motor regions, there are tens or even hundreds of different types of neurons. In fact, researchers are still trying to devise a way to neatly classify the huge variety of neurons that exist in the brain.
  
-Looking at which neurotransmitter a neuron uses is one way that could be a useful for classifying neurons. +Looking at which neurotransmitter a neuron uses is one way that could be useful for classifying neurons. 
-However, within categories we can find further distinctions. Some GABA neurons, for example, send their axon mostly to the cell bodies of other neurons; others prefer to target the dendrites. Furthermore, these different neurons have different electrical properties, different shapes, different genes expressed, and different projection patterns and receive different inputs. In other words, a particular combination of features is one way of defining a neuron type.+However, within categories, we can find further distinctions. Some GABA neurons, for example, send their axon mainly to the cell bodies of other neurons; others prefer to target the dendrites. Furthermore, these different neurons have different electrical properties, different shapes, different genes expressed, and different projection patterns and receive different inputs. In other words, a particular combination of features is one way of defining a neuron type.
  
-This is really the purpose of trying to classify neurons: in the same way as we can say that spinal cord sensory neurons bring sensory input from the periphery to the central nervous system, we would like to be able to say that the role of ‘neuron X’ in the hippocampus is to (for example) let you distinguish between similar but slightly different memories.+This is the purpose of trying to classify neurons. In the same way as we can say that spinal cord sensory neurons bring sensory input from the periphery to the central nervous system, we would like to be able to say that the role of ‘neuron X’ in the hippocampus is to (for example) let you distinguish between similar but slightly different memories.
  
-So the answer to the question ‘What types of neurons are there?’ isn’t something we can fully answer yet. In the spinal cord, it is pretty simple. But part of what gives the brain its complexity is the huge number of specialised neuron types. Researchers are still trying to agree on what these are, and how they should be classified. Once we can do that, we’ll be in a good position to delve even deeper into how the brain operates.+So the answer to the question ‘What types of neurons are there?’ isn’t something we can fully answer yet. In the spinal cord, it is pretty simple. But part of what gives the brain its complexity is the huge number of specialised neuron types. Researchers are still trying to agree on these and how they should be classified. Once we can do that, we’ll be in a good position to look even deeper into how the brain operates.
  
 =====THE BRAIN===== =====THE BRAIN=====
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 At the base of the brain is the brainstem. It is important for breathing, blood pressure and how the body reacts to danger. At the base of the brain is the brainstem. It is important for breathing, blood pressure and how the body reacts to danger.
 +{{:brain.jpg?400|}}
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 +=====Relationship between the CNS and the Limbic System =====
 +
 +{{:ls.jpg?400|}}
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 +  * Thalamus: Telephone exchange, all sense information less smell come here. It redirects the information to the relative areas. 
 +  * Hypothalamus is involved in the “hungers” and the “drives”
 +  * Hippocampus: highly involved in memory
 +  * Amygdala: Highly involved in emotional discrimination (Fight or flight response, trauma...)
 +
 +For more info inthe Limbic system:
 +
 +https://integraleyemovementtherapy.wiki/limbic_system
 +
 + 
  • Last modified: 2022/12/29 06:49
  • by andrewtaustin