0
The Nervous System        Mindy Milton, MPA, PA-C                   July 15, 2010
Neurological Anatomy• Neurons  – Functional units of the nervous system     • Fuel source is glucose     • Does not requir...
• Neurons  – Neuronal structure    • Anaxonic: small with no anatomical clues to      identify dendrite from axon    • Uni...
NEURON TYPES
Types of neuronal structure
Multipolar Neuron
Neuroglia                        OligodendrocytesAstrocyte                          EpendymalMicroglia                    ...
Neurological Anatomy• Synapse  – Definition: specialized site where the neuron    communicates with another cell  – Compon...
SYNAPTIC TRANSMISSION
NEUROMUSCULAR           JUNCTION• Anatomy:  – Axon terminal contains large numbers of    mitochondria that are important i...
Neurotransmitters    These have either excitatory functions, inhibitory or both•    Acetylcholine•    Norepinephrine•    S...
Cerebral Cortex• General Principles  – Each cerebral cortex receives information    from and sends motor commands to the  ...
Neurological Anatomy
Pre-Frontal Function•   Alertness and orientation•   Mood•   Attention•   Perception•   Memory•   Thought content•   Thoug...
Examination of pre-frontal function• Observation of alertness, dress, hygiene,  manor.• Coma scale, e.g. Glascow• General ...
CEREBRUM•       FRONTAL LOBE                • PARIETAL LOBE    –    Contains somatic motor       – Contains somatic sensor...
Homunculus
CEREBRUM• TEMPORAL LOBE – Hearing and speech is located in the   dominant hemisphere – Responsible for the interpretation ...
CEREBRUM• OCCIPITAL LOBE  – Vision and the visual interpretative area• CORPUS CALLOSUM  – Connects the two hemisphere’s an...
Neurological Anatomy• Cerebral Cortex  – Association areas: storage, analysis and    interpretation of sensory data    • S...
Neurological Anatomy• Integrative Areas  – Integrate information from multiple association areas    and direct complex mot...
Anatomy
CEREBRUM• BASAL GANGLION  – Exerts regulating,    controlling influences    on motor integration  – Numerous pathways    f...
DIENCEPHLON• THALAMUS  – Receives sensory    information for somatic    senses, taste, hearing, and    relays to cerebral ...
BRAIN STEM• MIDBRAIN  – Located between the Pons    and diencephalon  – Contains both motor and    sensory pathways  – Con...
Reticular Activating System
CEREBELLUM• CEREBELLUM  – Important in    synchronization of muscle    movement  – Monitors and makes    corrective moveme...
Neurological Anatomy: CSF• Produced by the choroid  plexus in the lateral, third  and fourth ventricles• Flow pathway   – ...
CSF• Allows passage of  nutrients between the  blood and extracellular  fluid of the brain• Reabsorbed by the  arachnoid v...
CSF• Cerebral Spinal Fluid  – Reabsorbed by the arachnoid villa secondary    to pressure gradient  – Arachnoid villa act a...
Hydrocephalus
MENINGES• Dura mater: tough outer meningeal  membrane that lies directly below the  skull. The epidural space lies between...
MENINGES• PIA MATER: is a vascular thin membrane  that covers the brain and the spinal cord  – Vessels pass between the pi...
Neurological Anatomy:Meninges
Spinal Cord• Spinal Cord Nerves  – Vertebrae     •   8 cervical     •   12 thoracic     •   5 lumbar     •   5 Sacral     ...
MOTOR SYSTEM• SPINAL CORD – Automatic reflex control – Thirty one pairs of spinal nerves with a   sensory and motor root –...
Spinal Cord View
SENSORY SYSTEM• Afferent transmission through posterior  (dorsal) horns of the spinal cord• Sensory tracts  – Spinothalami...
SENSORY TRACTS• POSTERIOR COLUMN  – Larger fibers that are myelinated with increased    degree of spatialization  – Carrie...
• Sensory Pathways•   Pain and temperature•   Cross at Cord level.•   Touch crosses at•   Medulla
Neuro Anatomy: Sensory Tracts
Neuro Anatomy: Sensory Tracts
MOTOR SYSTEM• MOTOR CORTEX – Initiation of the pyramidal tract in the large   Betz cells within the motor cortex – Impulse...
Motor pathways• Lower motor• Upper motor  – Pyramidal     • Fine discrete  – Extrapyramidal     • Coordination- cerebellar...
MOTOR TRACTS• CORTICOSPINAL -  PYRAMIDAL  – UMN Fibers pass from the    cell body of the Betz cell in    the motor cortex ...
MOTOR TRACTS• BASAL GANGLIA -  EXTRAPYRAMIDAL  – All tracts outside the    corticospinal system  – Controls body tone and ...
Motor Pathways• Most cross at Medulla in pyramid-shaped pathways.    – Some don’t crossSo whole tract is calledPyramidal t...
Neuro Anatomy: Motor Tracts
Cerebellar Function
Test Motor pathways• DTRs• Active range of motion     (include CN III, IV, VI, VII, XI, XII)• Gait• Romberg• Coordination
Blood Supply: CNS• General Concepts  – 20% of cardiac output per minute  – Blood supply controlled largely by changes in t...
Blood Supply: CNS• Circle of Willis  – Formed by posterior cerebral arteries,    posterior communicating arteries, interna...
Blood Supply: CNS
Blood Supply: CNS
Peripheral Nervous System•   Two Components    – Spinal and cranial nerves    – Autonomic Nervous system•   Spinal Nerves ...
Neurological Anatomy• Peripheral Nervous System  – All nervous tissue outside of the central nervous    system  – Importan...
Sensory System•   Smell•   Vision•   Hearing•   Taste•   Touch•   Pain•   Temperature•   Pressure•   Position•   Vibration
Testing the Sensory System•   Cranial nerves I, II, V, VII, VIII, IX, X•   Body sensory touch, pain, temperature•   DTRs• ...
Cranial Nerve: Olfactory
Cranial Nerve: Optic
Optic Nerve• The visual signalsof the right half ofboth eyes goesto left visual cortex
Cranial Nerve: Trigeminal
Cranial Nerve: Facial
Cranial Nerve: Acoustic
Cranial Nerve: Glossopharyngeal
Cranial Nerve: Vagus
• DermatomeDistribution
• Peripheral NerveDistribution
Lower Motor Neuron Pathway
Reflexes• Test sensory  perception• Sensory pathway• Sensory-motor  connection• Motor nuclei• Motor pathway• Muscle functi...
Autonomic system• Sympathetic• Parasympathetic•   Test largely by history•   Note skin temp, moisture,•   Vital signs•   P...
The End
Neurology s2010
Neurology s2010
Neurology s2010
Neurology s2010
Neurology s2010
Neurology s2010
Neurology s2010
Neurology s2010
Upcoming SlideShare
Loading in...5
×

Neurology s2010

862

Published on

Published in: Health & Medicine
0 Comments
1 Like
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total Views
862
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
37
Comments
0
Likes
1
Embeds 0
No embeds

No notes for slide
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • \n
  • Transcript of "Neurology s2010"

    1. 1. The Nervous System Mindy Milton, MPA, PA-C July 15, 2010
    2. 2. Neurological Anatomy• Neurons – Functional units of the nervous system • Fuel source is glucose • Does not require insulin for cellular uptake • Structure – Cell body: contains nucleus, neurofilaments, and neurotubules. Mitochondria active due to high energy needs, contain Nissl bodies that are responsible for the grey color of the neuron tissue – Dendrites: fine highly branched structures that are responsible for receiving information and transmitting to cell body – Axon: long projection that is capable of propagating an action potential
    3. 3. • Neurons – Neuronal structure • Anaxonic: small with no anatomical clues to identify dendrite from axon • Unipolar: single dendrite and axon that are essentially fused with cell body that lies off to the side • Bipolar: two distinct processes ie axon and dendrite • Multipolar: have two or more dendrites and a single axon
    4. 4. NEURON TYPES
    5. 5. Types of neuronal structure
    6. 6. Multipolar Neuron
    7. 7. Neuroglia OligodendrocytesAstrocyte EpendymalMicroglia Cellscells
    8. 8. Neurological Anatomy• Synapse – Definition: specialized site where the neuron communicates with another cell – Components • Pre-synaptic cell: neuron that sends the message • Post- synaptic cell: neuron or muscle cell that receives a message • Neurotransmitters: chemical substances that are released by the pre-synaptic cell and cause a change in electrical activity of the post-synaptic cell i.e stimulation of an impulse
    9. 9. SYNAPTIC TRANSMISSION
    10. 10. NEUROMUSCULAR JUNCTION• Anatomy: – Axon terminal contains large numbers of mitochondria that are important in the synthesis of acetylcholine – Acetylcholine is stored in multiple vesicles – Synaptic cleft: area between the axon and the muscle fiber – Sub neural cleft: invagination of the muscle fibers that increases surface area
    11. 11. Neurotransmitters These have either excitatory functions, inhibitory or both• Acetylcholine• Norepinephrine• Serotonin• Dopamine• Histamine• Gamma aminobutyric acid (GABA)• Glycine• Glutamate and Aspartate• Endorphin• Substance P
    12. 12. Cerebral Cortex• General Principles – Each cerebral cortex receives information from and sends motor commands to the opposite side of the body – Two hemispheres have different functions – Assignment of specific functions to a specific region of the brain is imprecise at this time
    13. 13. Neurological Anatomy
    14. 14. Pre-Frontal Function• Alertness and orientation• Mood• Attention• Perception• Memory• Thought content• Thought process• Insight• Judgment• Language
    15. 15. Examination of pre-frontal function• Observation of alertness, dress, hygiene, manor.• Coma scale, e.g. Glascow• General conversation and history-taking• Mental status examinations• Special scales, e.g., depression, alcohol
    16. 16. CEREBRUM• FRONTAL LOBE • PARIETAL LOBE – Contains somatic motor – Contains somatic sensory areas areas • Voluntary • Primary • Premotor area • Association • Eye fields – Important in the interpretation of sensory – Important in the control data of body movements – Loss is associated with – Loss is associated with difficulty recognizing inability to direct and objects, forms, or having a program movements sense of body parts
    17. 17. Homunculus
    18. 18. CEREBRUM• TEMPORAL LOBE – Hearing and speech is located in the dominant hemisphere – Responsible for the interpretation and understanding of speech – Major area of long term memory storage – “General Interpretative or Wernicke’s area” – Vestibular sense
    19. 19. CEREBRUM• OCCIPITAL LOBE – Vision and the visual interpretative area• CORPUS CALLOSUM – Connects the two hemisphere’s and helps coordinate activities between them. Transfers learned descrimination, experiences, and memories
    20. 20. Neurological Anatomy• Cerebral Cortex – Association areas: storage, analysis and interpretation of sensory data • Somatic association area • Visual association area • Auditory association area
    21. 21. Neurological Anatomy• Integrative Areas – Integrate information from multiple association areas and direct complex motor activity – General Interpretive Area: (Wernike’s Area) • Present in the left hemisphere • Receives information from all of the sensory association areas • Provides the ability to interpret what is seen and heard, coordinates access to complex visual and auditory memories – Broca’s area: • Motor neurons in the general interpretative area that coordinate the activity of the respiratory, pharyngeal, and muscles of the tongue, cheeks, and jaws
    22. 22. Anatomy
    23. 23. CEREBRUM• BASAL GANGLION – Exerts regulating, controlling influences on motor integration – Numerous pathways from the motor cortex – Dopamine and GABA found here and are responsible for inhibition of tone
    24. 24. DIENCEPHLON• THALAMUS – Receives sensory information for somatic senses, taste, hearing, and relays to cerebral cortex – System of connecting nuclei• HYPOTHALAMUS – Temperature regulation, thirst center, ADH release – Behavior: affective nature of sensory stimuli – Hormonal control
    25. 25. BRAIN STEM• MIDBRAIN – Located between the Pons and diencephalon – Contains both motor and sensory pathways – Contains the nuclei for the third and fourth cranial nerves• MEDULLA – Located between the Pons and spinal cord – Center for vegetative functions – Cranial nerve tracts for 8,9,10,11,12
    26. 26. Reticular Activating System
    27. 27. CEREBELLUM• CEREBELLUM – Important in synchronization of muscle movement – Monitors and makes corrective movements – Receives information from the motor and sensory cortex, and peripheral sensory receptors – Serves as feedback regulator – “Damping” of movement
    28. 28. Neurological Anatomy: CSF• Produced by the choroid plexus in the lateral, third and fourth ventricles• Flow pathway – Lateral ventricle – Foramen of Monroe – Third ventricle – Aqueduct of Sylvius – Fourth ventricle – Foramina of Luschka, Foramen of Magendi
    29. 29. CSF• Allows passage of nutrients between the blood and extracellular fluid of the brain• Reabsorbed by the arachnoid villi• Blood brain barrier: selective ability for substances to enter the brain through the capillaries of the choroid plexus.
    30. 30. CSF• Cerebral Spinal Fluid – Reabsorbed by the arachnoid villa secondary to pressure gradient – Arachnoid villa act as one way valve that moves CSF fluid out into blood – Obstruction of flow of CSF fluid will increase pressure within cranial cavity. – Hydrocephalus is the result of increased CSF
    31. 31. Hydrocephalus
    32. 32. MENINGES• Dura mater: tough outer meningeal membrane that lies directly below the skull. The epidural space lies between the dura and the skull• Arachnoid: middle meningeal membrane with tissue arranged in a web like fashion. Cross the subdural space and reabsorb CSF
    33. 33. MENINGES• PIA MATER: is a vascular thin membrane that covers the brain and the spinal cord – Vessels pass between the pia and the arachnoid through the subarachnoid space
    34. 34. Neurological Anatomy:Meninges
    35. 35. Spinal Cord• Spinal Cord Nerves – Vertebrae • 8 cervical • 12 thoracic • 5 lumbar • 5 Sacral • 1 coccygeal – Divided into sensory and motor pathways
    36. 36. MOTOR SYSTEM• SPINAL CORD – Automatic reflex control – Thirty one pairs of spinal nerves with a sensory and motor root – Anterior Horn cells are large myelinated motor neurons that terminate on skeletal muscle
    37. 37. Spinal Cord View
    38. 38. SENSORY SYSTEM• Afferent transmission through posterior (dorsal) horns of the spinal cord• Sensory tracts – Spinothalamic • Small myelinated/non-myelinated fibers • Poorly localized sensation of crude touch, pain, temperature • Fibers synapse quickly on entering the spinal cord and cross over to the opposite side
    39. 39. SENSORY TRACTS• POSTERIOR COLUMN – Larger fibers that are myelinated with increased degree of spatialization – Carries fibers for touch requiring localization, vibratory sense, and position sense – Travels up same side of cord and synapses with second order neuron that travels to thalamus – Well spatialized: organized for increased ease of sensory interpretation and localization
    40. 40. • Sensory Pathways• Pain and temperature• Cross at Cord level.• Touch crosses at• Medulla
    41. 41. Neuro Anatomy: Sensory Tracts
    42. 42. Neuro Anatomy: Sensory Tracts
    43. 43. MOTOR SYSTEM• MOTOR CORTEX – Initiation of the pyramidal tract in the large Betz cells within the motor cortex – Impulses sent down to the motor tracts with collateral messages to the cerebellum, basal ganglia, and reticular activating system
    44. 44. Motor pathways• Lower motor• Upper motor – Pyramidal • Fine discrete – Extrapyramidal • Coordination- cerebellar • Tone- mid-brain
    45. 45. MOTOR TRACTS• CORTICOSPINAL - PYRAMIDAL – UMN Fibers pass from the cell body of the Betz cell in the motor cortex through the brain stem down the opposite side of the cord – Responsible for fine discrete motor movement – Synapse with inter-neurons or anterior horn cells in the spinal cord – Necessary for voluntary movement – Excitatory in nature
    46. 46. MOTOR TRACTS• BASAL GANGLIA - EXTRAPYRAMIDAL – All tracts outside the corticospinal system – Controls body tone and gross body movements• Cerebellum – Sensory and motor input – Controls posture and coordination
    47. 47. Motor Pathways• Most cross at Medulla in pyramid-shaped pathways. – Some don’t crossSo whole tract is calledPyramidal tract.
    48. 48. Neuro Anatomy: Motor Tracts
    49. 49. Cerebellar Function
    50. 50. Test Motor pathways• DTRs• Active range of motion (include CN III, IV, VI, VII, XI, XII)• Gait• Romberg• Coordination
    51. 51. Blood Supply: CNS• General Concepts – 20% of cardiac output per minute – Blood supply controlled largely by changes in the level of carbon dioxide• Arterial Blood Flow – Internal carotids enter through the skull, branch into the anterior and middle cerebral arteries – Vertebral arteries: originate from the subclavian, enter the skull through the foramen magnum, join to form the basilar artery, that will then divide and form the posterior cerebral arteries
    52. 52. Blood Supply: CNS• Circle of Willis – Formed by posterior cerebral arteries, posterior communicating arteries, internal carotid arteries, anterior cerebral arteries, and anterior communicating arteries – Ring shaped anastomosis allows for protection of blood flow interruption from the vertebral or carotid arteries
    53. 53. Blood Supply: CNS
    54. 54. Blood Supply: CNS
    55. 55. Peripheral Nervous System• Two Components – Spinal and cranial nerves – Autonomic Nervous system• Spinal Nerves – Mixed nerves as they contain both sensory and motor neurons – Divide and form posterior and anterior rami – Anterior rami then form plexuses • Brachial plexus: C 5-8 and T1 innervates the nerves of the arm, wrist, and hand • Lumbar plexus: L2-4 and sacral plexus: L5-S5 innervate the anterior and posterior portions of the lower body – Posterior rami form dermatomes that are distributed to specific areas of the body – Cranial Nerves: Most are mixed nerves that arrive from nuclei in the brain or brain stem
    56. 56. Neurological Anatomy• Peripheral Nervous System – All nervous tissue outside of the central nervous system – Important in the delivery of sensory data to the CNS and transmission of motor commands from the CNS – Two divisions • Afferent: brings sensory data into CNS • Efferent: transmits motor information from CNS – Somatic nervous system: skeletal muscles – Autonomic nervous system: visceral motor system
    57. 57. Sensory System• Smell• Vision• Hearing• Taste• Touch• Pain• Temperature• Pressure• Position• Vibration
    58. 58. Testing the Sensory System• Cranial nerves I, II, V, VII, VIII, IX, X• Body sensory touch, pain, temperature• DTRs• Vibratory• Position• Romberg
    59. 59. Cranial Nerve: Olfactory
    60. 60. Cranial Nerve: Optic
    61. 61. Optic Nerve• The visual signalsof the right half ofboth eyes goesto left visual cortex
    62. 62. Cranial Nerve: Trigeminal
    63. 63. Cranial Nerve: Facial
    64. 64. Cranial Nerve: Acoustic
    65. 65. Cranial Nerve: Glossopharyngeal
    66. 66. Cranial Nerve: Vagus
    67. 67. • DermatomeDistribution
    68. 68. • Peripheral NerveDistribution
    69. 69. Lower Motor Neuron Pathway
    70. 70. Reflexes• Test sensory perception• Sensory pathway• Sensory-motor connection• Motor nuclei• Motor pathway• Muscle function• Neurotransmitters.• Flexible joint
    71. 71. Autonomic system• Sympathetic• Parasympathetic• Test largely by history• Note skin temp, moisture,• Vital signs• Pupillary response to light, accommodation
    72. 72. The End
    1. A particular slide catching your eye?

      Clipping is a handy way to collect important slides you want to go back to later.

    ×