The Nervous System and Brain

The Nervous System and Brainof the Human Nervous SystemContents∙Introduction∙Nervous System∙Neuron Function∙Brain Stem∙∙∙∙∙ɡdələ]∙ə'kæmpəs]Introductionthoughts, and memories. To them, the brain was nothing but a giant glob of mucus that passed snot down to the nose. [1] For hundreds or even thousands of years, thethe 20th and 21st century, and sciences. We are getting closer and closer to understanding each and every part of thetheir brain waves. [2]which we now comprehend our brain and nervous system is impressivethe least.Nervous Systemsent to the brain through the nervous system. LikewiseThe nervous system is an intricate mostly of nerve cells (orover 50 variations to the requirements the central nervous system and the peripheral nervous system.Central Nervous System (CNS)the backbone called the meningesalso acts as protection for the CNS. All of theseprotective factors are vital for our survivallead to serious injury or death.Peripheral Nervous System(PNS)The peripheral nervous system is comprised of the branches of nerves that extend from the central nervous system to the rest of our body. [6] These nerve fibers are notto damage. There are a number of different kinds of nerve cells that are part of ∙Afferent Neurons - Nerves in the peripheral nervous system that carrynerves). [4] Afferent neurons communicate with interneurons thatlegs or arms, are sent along afferent neurons to the brain where the pain can be registered.∙Efferent Neurons - Also known as motor neurons, efferent neurons (or nerves) body. [7] Efferent neurons, for example, keep our hearts beating, our lungsbreathing, and also allow us to move our bodies.Interneurons - These are mostly found in the spine and brain. Interneurons connect nerves to other nerves and therefore do not connect to any muscles or other sensory cells. They can connect afferent neurons to efferent neurons. There are about 100 billion interneurons in the human body. [8]- Keeping all of the nerves protected and in place are the glial cells. There are around ten times as many glial cells as there are other neurons in the brain. [9] They surround neurons and 'glue' our neural networks together. They alsoand helpcontrol neurotransmission.Neuron FunctionThe nervous system is extremely complex and has around 100 billion neurons thatactionpotentialthrough the membrane in the cellNeurons react to neurotransmittersnorepinephrineaxonsDendrites - These are branch projections stemming out of a neuron that bringpotentials and integrating synapses. [10] They reach out to surrounding neurons detected an electrical signal it will send it down into the cell body it is branched out from. There can be many dendrite branches on one neuron.Axons - Also known as nerve fibers, these are projections which take information away from the cell. [11] Much like dendrites, they branch away from the cell body and have electrical impulses coursing through them, only this time they are heading away from the cell body. There can be only one axon on each neuron.∙- Axons are insulated with a myelin sheath thatultimatelygaps called Nodes ofRanviersaltatory conduction and then continue on into myelin. This keeps the Synapsesions, is able to pass. Synapses are very tiny gaps that allow signals to diffuse fromparts: a presynaptic ending, and synaptic cleft. [12]∙Presynapticcell organelles∙Postsynaptic site for neurotransmitters.∙Synaptic Cleft- A space between the presynaptic and postsynaptic dendrites.Axoaxonic vesiclesterminals receive will determine whether or not the cell will decrease the strength of the signal. The electrical impulses received in the cell are called action potentials. Action potentials continually repeat as the brain and its neurons do their job.Brain Stemtwo and is called the brain stem (reptilian brain). The brain stem goes from the entire nervous system. [13] There are three parts that make up the brain stem.∙Medulla Oblongatablood pressure, and digestion. It also relays nerve signals between the brain∙Pons- Above the medulla oblongata is the pons. The pons helps theinformation that helps us with our movement, arousal∙Midbrainthe body's sensory and motor functions.The CerebellumThe cerebellum sits behind the brain stem at the base of the entire brain. Though the cerebellum is about one tenth of the entire brain's volume it houses almost half therunning across it and is therefore more compact than the rest of the brain. Thecerebellum has two hemispheres and was one of the first parts of the brain to ever evolve. [15] It is one of the most important parts of the brain for its ability to integratemovement, as well as deciphering information from the ears and eyes. Some scientists also believe that the cerebellum helps us process language and music and gives us our ability to pay attention, among other things. [14] The cerebellum sends information into the brain stem which is then delivered to the rest of the brain.The DiencephalonBetween the cerebral hemispheres and above the midbrain there is a region of the brain called the Diencephalon. It contains two very important substructures.∙Thalamus - A dual-lobed structure made of grey matter, the thalamus receives and deciphers sensory information. [16] Once it has processed sensoryinformation the thalamus chooses whether or not that information should berelayed to the cortex. The thalamus receives information from parts of thebrain and body that have to do with movement and sensory information.Signals from the cerebellum and cerebral cortex are sent to the thalamus andthe thalamus sends signals out into the cortex.∙Hypothalamus - The hypothalamus is in charge of making sure that we stay motivated. It sits beneath the thalamus and is connected to most everything inthe brain. The hypothalamus causes us to seek pleasurable activities likehormonesbehave. [17] The hypothalamus also manages the circadian rhythmbody temperature, and instinctualLimbic SystemThe limbic system is comprised of a group of brain structures that are important in the processing of information and the formation of memories and emotions. There are three key areas in the limbic system.The Basal GangliaThe basal ganglia is connected to the thalamus and cortex. It is comprised of a group of structures that sit inside of the brain and look like two curving tubes. The basal ganglia receives most of its information from the cortex and is critical to our ability to move. [18] When the basal ganglia is damaged it severely impairs someone's ability to control their body, as can be seen in those with Hutchinson's Disease or Parkinson's Disease.Amygdalaand well-beingpart in causing arousalamygdala. [19]Hippocampusshaped somewhat like a seahorse. The hippocampus is key in creating new memories by forging new neural pathways in our minds. [20] The hippocampus also helps us with spatial orientation and sleep patterns.The Cerebral CortexThe cerebral cortex is the largest, most apparent part of the brain. It is the outer layer of the brain that is the main source of human intelligence. The cerebral cortex isfoldedhas six different layers with many neural networks. Beneath these layers is white matter and when all of these are put together we are given a huge number of connections that facilitate our ability to think, feel, and reason.The cerebral cortex has two hemispheres and each hemisphere helps to manage different things and perform various tasks. Both the hemispheres can communicate with one another, and can be divided into four different lobes.∙Frontal Lobe- The frontal lobe is behind and beneath the forehead. It gives humans their higher level thinking skills, such as the ability to plan, pay attention, use language, and move. [21] It is able to control much of the other areas of the brain. The frontal lobe can also help us to form memories. It gives us the ability to decide how we want to act based on the information we∙Parietal Lobesensory input and give us perceptionlinked to visual systems, the parietal lobes help us to do things like button our shirts or throw footballs. [22]∙Occipital Lobe- The occipital lobes make up the main visual processingourselves with the external world. Without the∙Temporal Lobe- The temporal lobe spans across the brain and is below processing auditory information. [24] This auditory processing center helps usmakes it important in the formation and retrievalCorpus CallosumThe corpus callosum connects the brain's two hemispheres together. It is a hugebrain. [25] The corpus callosum allows for optimal performance from the brain.Some epilepsyhow the corpus callosum affectsconsciousnessConclusionsummed up all of the majoron to try and unravel the secrets of the brain and nervous system. We know a lot understand these parts of our bodies, the better we can understand humans and their societies as a whole.References1.OzInc/featurestories/heart.htm2.Drexel University. Students Develop 'Mind-Control' Interface to Play VideoGames Without a Controller. PhysOrg/news137776590.html3. A 'Frankenrobot' with a biological brain. PhysOrg./news137852322.html4.Afferent Neuron. The Free Dictionary./afferent+neuron5.The Human Central Nervous System. 12 April 2008/jkimball.ma.ultranet/BiologyPages/C/CNS.htmlanization of the Nervous System. 21 October 2007/jkimball.ma.ultranet/BiologyPages/P/PNS.html7.Efferent Neuron. The Free Dictionary./efferent+neuron8.Interneuron: Definition and Much More. ./topic/interneuron9.Chudler, Eric. Glia: The Forgotten Brain Cell. Neuroscience for Kids./chudler/glia.html10.Dendrites. Rensselaer Polytechnic Institute./locker/56/000756/dendrite.html11.Definition of Axon. MedicineNet, Inc./script/main/art.asp?articlekey=779712.Making Connections - The Synapse. University of Washington./chudler/synapse.html13.Guides, R., (2007). The Rough Guide to the Brain 1. London: Rough Guides.14.Rapp, Brenda (2001). The Handbook of Cognitive Neuropsychology: WhatDeficits Reveal about the Human Mind. Psychology Press15.cerebellum. (2008). In Encyclopædia Britannica. Retrieved August 14, 2008/EBchecked/topic/103357/cerebellum16.thalamus. Medical Science 532. University of Idaho./med532/thalamus.htm17.Farr, Gary. The hypothalamus. Become Healthy Now./article/bodynervousadvanced/956/ 18.BASAL GANGLIA AND CEREBELLUM. Washington University in St.Louis./course/cerebell.html19.Anatomy of the Brain. : Biology./library/organs/brain/blamygdala.htm20.Memory, Learning, and Emotion: the Hippocampus. PsychEducation./emotion/hippocampus.htm21.Frontal Lobes. Centre For Neuro Skills./tbi/bfrontal.shtml22.Parietal Lobes. Centre For Neuro Skills./tbi/bparieta.shtml23.Occipital Lobes. Centre For Neuro Skills./tbi/boccipit.shtml24.Temporal Lobes. Anatomy of the Brain. : Biology./library/organs/brain/bltemporallobe.htm25.THE HUMAN CORPUS CALLOSUM. University of Indiana./~pietsch/callosum.html。