1. Glial Cells 
    • 10-50 times more gila than neruons 
    • supporting cells 
  2. roles of glia 
    • support
    • clean up(dead cells and waste) 
    • regulation 
    • blood brain barrier 
    • nourishment 
  3. (Glial)
    • folowing trauma they engulf and breakdown dead and dying neurons 
    • active following injuring, infection or stroke (like the wbc of the brain) 
    • little known of function at resting state 
    • role in diseases MS AIDS PD and Alzheimers 
  4. Macroglia 3 types 
    • Oligodendroytes 
    • schwann cells 
    • astrocytes 
  5. Olifodendrocytes and Schwann cells 
    • funtion: insulation of axons= myelin sheath 
    • Oligoes---CNS 15 axons
    • schwann PNS only 1 axon 
  6. Astrocytes 
    • function: Nutrients(provide and connect) 
    • BBB 
    • neurotransmitter removal 
    • clean up gets rid of scar tissue 
    • support 
    • CNS 
    • doesn't form mylien sheath 
  7. Blood Brain barrier 
    semipermeable barrier produced by the cells walls of the capillaries in the brain 

    tight junctions between cells making it difficult for some substances to pass from the blood stream to the brain 
  8. 2 ways through BBB 

    Passive transport(diffusion) 
    • gases and water diffuse readily
    • some drugs: loperamind vs morphine ...herion passes faster than morhpine 
    • alcohol 
  9. through BBB 

    active transport 
    • energy sources: glucose, amino acids 
    • ions(na+ k+cl-) 
    • vitamins some hormones and peptiedes 
    • gets acrsoss through astroyctes 
  10. BBB weak?
    • BBB is weaker in some areas of the brains capillaries 
    • area postrem located in the brain stem(vomit reflex) 
    • pituitary gland(hormone release) 
  11. Neurons 
    • basic unit of the nervous system 
    • specialized cells that recieve info and transmit it to other cells by conducting electrochemical impulses 
  12. Neurons similarites to other cells 
    • Nucleus--dna 
    • endoplasmic reticulum--ribosomes 
    • mitochondrion--energy 
    • plasma membrane ---lipid bilayer studded with protein comples impermeable 
    • cytosketleton 
  13. Shape (morphology) neruon 
    • Branching 
    • reflects communication property 
  14. soma 
    cell body, nucleus, er, mitochondria 
  15. dendrites 
    recipeients of messages from other neurons 
  16. axon 
    simgle process  that leaves the soma and carries messages to the trminal buttons (to other neurons ) 
  17. myelin sheath 
    insulation to carry message more efficeitly 
  18. terminal buttons 
    branches at the end of the axon where neurotransmitters are releases 
  19. synapse 
     junction between terminal button of one axon and teh membrane of anohter neroun 
  20. Neurons: Energy requirement 
    • lots of mitochrodra 
    • need a lot of glucose and 02 
    • but have little ability to store enregy 
  21. Neurons: Limited cell division 
    • esp in adults 
    • don't replicate very often 
  22. Nuerons functions 
    info processing an transmission
  23. Unipolor 
    • invertebraes --communication 
    • simpliest 
    • 1 primary process to many branches 
  24. bipolor 
    • processing sensory neurons 
    • soma to 2 processes 
  25. multipolar 
    • most common 
    • CNS spinal cord and brain 
    • single axon many dendrites 
    • multipolar interneuron don't have a defined axon signal motifiers to spinal cord 
  26. sensory neurons 
    info from external environment 
  27. motor neurons 
    CNS to muscles and glands 
  28. Interneurons 
    • Lie completely in CNS  
    • Function: perceiving learning decision making complex behaviors 
  29. Principle of dynamic polarization 
    electrical signals witin a neuron flow in one direction:from reveiving site to axon, From there AP is unidirectional axon to presynaptic terminal 
  30. principle of connectional specificity 
    neurons do not connect indiscriminately with one another to form random networks each cell maes specific connections 
  31. membrane potential 
    charge across the neurons membrane created by electrical polarization 
  32. polariation 
    • outside of the neuron is postive inside is negative 
    • represented with - -(70mV) 
  33. membrane potential 
    • resting membrane (-70mV) 
    • depolarization--increase in the membrane potential( inside becomes more like the outside ) towards 0 EXCITE 
    • hyperpolarization ---decrease in the membrane potential (inside becomes more negative) INHIBIT
  34. how is resting membrane potential created 
    •  ions(charged particles) are balanced inside and outside of the cell 
    • cations:positvely charged 
    • anions negatively charged 
  35. Passive diffusion 
    • membrane is somewhat permeable to NA=and K= 
    • na+ outside: force of diffusion want Na+ to come in 
    • k+ inside:force of diffusion want K+ to go out 
    • electostatic pressure: like repels like (electrostatic gradient ) 
  36. active transport 
    • na/k pump
    • protein in cell membrane that moves k in 2 and na= in 3 using atp 
  37. Resting Membrane potential 
    • net result of diffusion and na/k pump is resting membrane potential 
    • na outside wants in 
    • k inside wants out 
    • Na just waiting for the membrane permeability to increase 
  38. action potential 
    • brief change in the permeability of the membrane such that the mebrane potential depolarizes 
    • stimuli from other neurons open ion channels 
  39. Na in k out 
    • na channels open first and na rushed into the cell 
    • k channels open later and k rushes out of the cell 
    • the cell depolarizes 
    • (membrane potential becomes more positve more positive inside the neuron) 
  40. return to resting potential 
    • when cell is depolarized 
    • na channels close 
    • k channels stay open though 
    • then the na/k pumps restores resting potential 
    •          requires a lot of energy3 na go out 2 k pumped in 
  41. Fun facts about neurotoxins and drugs 
    • na channels 
    • novocain, cocaine, lidocaine block na channels to prevent depolarzation (tempory and local) 

    • tetrodotoxin 
    • pufferfish, sewts and frogs 
    • permanent blockers of na channels 
  42. cable properties 
    the passive conduction of electrical current in a decremental fashion, down the length of an axon 
  43. saltatory conduction 
    conduction of action potentials by myelinated axons the action potential apperars to jump from one node of Ranvier to the next  
  44. advantages of myelination 
    • energy
    • a. less atp requried to pump na out and reset the system 
    • speed 
    • a. transmission under mylein sheath is much faster 
    • roughly 90 ms vs 10-20ms 
  45. synaptic transmission 
    • when action potential reaches terminal buttons, what happens? 
    • electrochemical transmission ---electric=action potential 
    • chemical=neurotransmitters 
    • neurotransmitters chemicals that communicate between neurons at the synapse 
  46. binding site 
    the location on a receptor protein to which a ligand binds 
  47. ligand 
    a chemical that binds with the binding site of a receptor 
  48. synaptic vesicle 
    a small hollow bead like structure found in  terminal buttons, contains molecules of a transmitter 
  49. ionotropic receptors
    • ligand dependent ion channel
    • ion channel that opens when a nT binds to it (fast) NT depended 
  50. metabotropic receptor (G protein linked ) 
    • receptor is adjacent to ion channels 
    • when nt binds it causes a cascade of intracellular events that open nearby ion channels (slower)

    determine gender in babies ...digestion
  51. Turning off synaptic transmission 
    • reuptake=NT is taken up by the presynaptic cell via a membrane transporter 
    • metabolism(enzymatic degredation)=NT is broken down in the synapse 
    • autorecptors=resynaptic receptors that detect the level of NT in the synapse 
  52. Communication between neurons 
    • intensity of nervous systems response is regulated by rate ( how many neryons fire ) 
    • most neurons fire at a basal rate all the time (stimuli can excite--increase firing) or inhibit 
  53. factors that influence firing rate 
    type of input 
    • excitatory post-synaptic potential(EPSP;+) 
    • inhibitory post-synaptic potential(IPSP;-) 
  54. factors that influence firing rate 
    how many +- inputs the neruon recieves and whether they occur at the same time 
  55. factors ......
    Input's distance from axon 
    spatial summation 
  56. dorsal 
    toward teh back, top of hand and back 
  57. ventral 
    towards the belly 
  58. rostral(anterior) 
    towards the face 
  59. caudal(posterior) 
    towards the tail 
  60. medial 
    toward the midline 
  61. lateral 
    away from the midline 
  62. coronal(transverse) 
    ear to ear 
  63. sagittal 
    between the eyes 
  64. horizontal 
    like taking off a hat 
  65. bilateral 
    both sides 
  66. contralateral 
    on opposite sides (vison) 
  67. ipsilateral 
    on the same side 
  68. CNS 
    brain and spinal cord 
  69. PNS 
    • cranial nerves 
    • somatic ns 
    • autonomic ns 
    •   sympatheicNS (fight or flight) increase pulse 
    •    parasympathtic 
  70. meninges 
    3 layers of protective sheaths around the CNS 
  71. dura mater 
    • hard mother 
    • outer layer 
    • thick tough but flexible 
  72. aracnoid membrane 
    • web like 
    • soft and spongy 
    • only in CNS 
  73. pia matter 
    inner thin layer that continues around the NS 
  74. PNS is covered with dura matter and pia mater only 
  75. ventrical system 
    hollow spaces in the brain that contain CSF
  76. cerebrospinal fluid 
    clear fluid that fills the subarachnoi space and the ventricles of the brain and spinal cord 

    supports and protects teh brain from damage and its own weight 
  77. Ventricular system 
     csf is produced by a special sturctre in the ventricles called the choroid plexus 

    • entire volume replaced every 6 hours 
    • fluid fills the ventricles and surrounds the brain
    • desends into a tube in the center of the spinal cord central cannal 
  78. flow of csf 
    • Choroid plexus 
    • lateral ventricle 
    • 3rd ventricle cerebral aqeduct 
    • 4th ventricle 
    • subaranoid space ---central canal 
    •                arancoid villius /granulations 
  79. spinal cord 
    links the pns to the brain(not the crainal nerves) 
  80. white matter 
    axons carrying info up or down 
  81. gray matter 
    cell bodies 

    Central canal=filled with CSF
  82. PNS 
    somatic body nervous system 
    • relay of sensory signals to cns and motor signals from cns to skeletal muscles 
    • sensory nerves--enter dorsal side of spinal cord 
    • motor nerves---exit ventral side of spinal cord 
    • cranial nerves--leave right to the brain 
  83. PNS 
    Autonomic nervous system 
    • automatic 
    • regulates cardiac muslces smooth muscles and glands 

    • sympathetic NS fight or fligh energy use 
    • parasympathetic --resores/maintains homeostatis 
    • energy saving 
  84. Endocrine system 
    System of glands that release hormones under the direction of the pituitary gland

    Hormones --chemical messengers that travel through the bloodstrem(loose junctions..pitutary )

    • Hormones can have effects on the CNS
    • Can easily cross the BBB (feedback system)
    • Bind to both

    • Membrane-bound receptors
    • Intracellular receptors (transcription factors… make new proteins)
  85. Hindbrain 
    controling vital functions heart rat resp vomit cough sneeze reflexes muscle tones 
  86. hindbrain 
    • reticular formation--extends from medulla through the pons to midbrain 
    • controls sleep/wake cycle 
    • alterness to external stimuli 
    • norephinephrene projections throughout the brain

    • raphe system(nuclie)--control of internal alertness
    • mental vigilance 
    • serotonergic projections throughout the brain 
  87. hindbrain 
    • coordinations of voluntary movement complicated motor movement 
    • imput from motor cortex spinal cord sensory neurons and inner ear 
  88. midbrain 
    Tectum (above cerebral aqueduct)

    Superior & inferoir colliculi--visual and auditory reflexes(something out of the corner of your eye) 

    Tegmentum (below cerebral aqueduct)
  89. Forebrain 
    • Cerebrum: cerebral cortex (bark)
    • 4 lobes

    • Frontal-judgement, iniciates movement
    • Parietal--sensation
    • Occipital--vison
    • Temporal--hearing 
  90. sulcus 
    • groove in the surface of teh cerebral hemisphere 
    • smaller than a fissure 
  91. fissure 
    • major groove in teh surface of the brain 
    • long deep cut 
  92. gyrus 
    • convoltion of the cortex of teh cerebral hemisphere separated by sulcus of fissure 
    • big bumps 
  93. CNS
    primary visual cortex

    The region of the ___back of the brain upperand lower banks of calcarine fissure_ whose primary input is from the visual system.

    primary auditory cortex

    The region of the ___lower surface of lateral fissure__ whose primary input is from the auditory system.

    lateral fissure--The fissure that separates the temporal lobe from the overlying frontal and parietal lobes.

    primary somatosensory cortex

    The region of the ___caudal to central suclus__ whose primary input is from the somatosensory system.

    primary motor cortex

    The region of the _posterial frontal lobe__ that contains neurons that control movements of skeletal muscles.
  94. Subcortical forebrain structures 
    • Corpus callosum = commissure 
    • connection between teh 2 cerebral hemisphers 

    Thalamus = sensory relay station (train station) connects body senses to the cerebrum

    • Lateral geniculate nucleus = eye to CTX
    • Medial geniculate nucleus = ear to CTX

    • Hypothalamus
    • involved in everything regulate temp and hormone production
  95. Subcortical forebrain structures 
    • limbic system(motivation, emotion, memory ) 
    • amygdala( almond shaped, anterior temporal lobe) 
    • fear anger emotions defensive and agressive behavior at tip of hippocampus 

    hippocampus--learning declaritive momories shaped like a ram horn 

    fornix--connects hippocampus to other parts of the brain 
  96. Subcortical forebrain structures 
    Basal Ganglia (3 seperate group of cells)

    • Caudate nucleus
    • Globus pallidus
    • Putamen--important parts of the motor system control of balance and movement connected to substantia nigra 

    Connect to substantia nigra (nigrostriatal DA pathway) and motor areas of CTX
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