The central nervous system presentation dawn part 1
Upcoming SlideShare
Loading in...5
×

Like this? Share it with your network

Share
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Be the first to comment
No Downloads

Views

Total Views
555
On Slideshare
555
From Embeds
0
Number of Embeds
0

Actions

Shares
Downloads
29
Comments
0
Likes
2

Embeds 0

No embeds

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
    No notes for slide

Transcript

  • 1. BY DAWN V TOMY M.PHAM., DEPT. OF PHARMACOLOGY, ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA. Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA. 1
  • 2. TITLES 1. STRUCTURE OF THE BRAIN. 2. STRUCTURE OF THE SPINAL CORD. 3. FUNCTIONS OF THE CEREBRUM. 4. FUNCTIONS OF THE CEREBELLUM. 5. FUNCTIONS OF THE VITAL CENTERS OF THE MEDULLA OBLONGATA. 6. CEREBRO SPINAL FLUID (CSF). 7. CEREBRAL VENTRICLES. 8. CRANIAL NERVES. 9. FUNCTIONS OF CRANIAL NERVES. 10. DISORDERS OF THE CNS. Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA. 2
  • 3. CENTRAL NERVOUS SYSTEM (CNS) 3 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 4. Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA. 4 INTRODUCTION • The central nervous system (CNS) consists of the brain and spinal cord. • The brainstem connects the brain to the spinal cord. • Brain communicate with the peripheral nervous system (PNS) through the spinal cord.
  • 5. ANATOMY OF THE BRAIN Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA. 5
  • 6. • The brain is situated in the cranial cavity formed by the cranial and facial bones. It is protected by the meninges. It is nourished and cushioned by the Cerebrospinal Fluid (CSF) formed in ventricles. Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA. 6
  • 7. A. STRUCTURE OF THE BRAIN. 7 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 8. Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA. 8 An adult brain weighs between 1.3 to 1.4 kg and has a volume of about 1200 cc.
  • 9. BRAIN 9 Major parts of the brain: •Cerebrum • Frontal lobes • Parietal lobes • Occipital lobes • Temporal lobes • Insula •Diencephalon •Epithalamus •Thalamus •Subthalamus and •Hypothalamus •Brainstem • Medulla oblongata •Pons •Midbrain •Cerebellum Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 10. 10 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 11. 11 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 12. B. FUNCTIONS OF THE BRAIN. 12 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 13. 13 • It helps to maintain homeostasis. • Interprets sensations. • Determines perception. • Stores memory. • Reasoning. • Makes decisions. • Coordinates muscular movements. • Regulates visceral activities. • Determines personality. FUNCTIONS OF THE BRAIN. Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 14. Brain Development 14 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 15. BLOOD FLOW. 15 Supply: Internal carotid and vertebral arteries. Return: Internal jugular veins (from head to heart) Interruption in blood flow to brain for 30 sec imparts neuronal function, if it is for 4 min it causes permanent damage, as brain does’t have glucose and oxygen store. Low level of glucose in brain leads to mental confusion, dizziness, convulsions and loss of consciousness. Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 16. BLOOD BRAIN BARRIER (BBB). 16 The endothelial cells of the brain capillaries along with thick basement membrane and astrocytes forms tight junctions which selectively passes substances from blood to brain. Glucose crosses BBB by means of active transport. Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 17. CSF AND CEREBRAL VENTRICLES. 17 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 18. Ventricles and Cerebrospinal Fluid 18 • There are four (4) ventricles • The ventricles are interconnected cavities within cerebral hemispheres and brain stem • The ventricles are continuous with the central canal of the spinal cord • They are filled with cerebrospinal fluid (CSF) • The four (4) ventricles are: • Lateral ventricles (2) • Known as the first and second ventricles • Third ventricle • Fourth ventricle • Interventricular foramen • Cerebral aqueduct Lateral ventricle Third ventricle Fourth ventricle (a) Interventricular foramen Cerebral aqueduct To central canal of spinal cord Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Third ventricle (b) Cerebral aqueduct To central canal of spinal cord Fourth ventricle Lateral ventricle Interventricular foramen Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 19. 19 A lateral ventricle is located in each hemisphere of the cerebrum. Anteriorly, the lateral ventricles are separated by a thin membrane, the septum pellucidum. The 3rd ventricle is a narrow cavity along the midline; superior to the hypothalamus and between the right and left halves of thalamus. The 4th ventricle lies between the brain stem and the cerebellum. The 4th ventricle is continous with the central canal of spinal cord. Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 20. 20 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 21. Formation of CSF in the ventricles. 21 CSF is produced in the choroid plexuses which are network of capillaries in the walls of the ventricles. The ependymal cells that cover the capillaries form cerebrospinal fluid from the blood plasma by filtration and secretion process. The ependymal cells joined by tight junctions in the choroid capillaries forms the blood-cerebrospinal fluid barrier permitting selective diffusion, thereby protecting the brain and spinal cord from potentially harmful blood-born substances. Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 22. Cerebrospinal Fluid 22 •Circulates in ventricles, central canal of spinal cord, and the subarachnoid space • Completely surrounds the brain and spinal cord • Excess or wasted CSF is absorbed by the arachnoid villi • It is a clear fluid similar to blood plasma • Volume is only about 120 ml. • Nutritive and protective function. • Helps maintain stable ion concentrations in the CNS. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Third ventricle Fourth ventricle Cerebral aqueduct Subarachnoid space Arachnoid mater Dura mater Pia mater Pia mater Central canal of spinal cord Subarachnoid space Filum terminale Arachnoid mater Dura mater Arachnoid granulations Choroid plexuses of third ventricle Blood-filled dural sinus Choroid plexus of fourth ventricle Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 23. 23 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 24. THE COMPOSITION OF CSF. 24 The composition of CSF: Total volume of CSF is 80 to 150mL in an adult. It contains Glucose, Proteins, Lactic acid, Urea, Cations (Na+, K+, Ca2+ and Mg2+) and Anions (Cl- and HCO3 -). It also contains WBCs. Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 25. 25 Functions of CSF: The CSF contributes to brain and spinal cord homeostasis in 3 ways. 1. Mechanical protection: It serves as shock absorbing medium that protects the delicate tissues of the brain and spinal cord from impacts by not letting them hit the bony walls of the cranial and vertebral cavities. The fluid also buoys the brain floating it in the cranial cavity. 2. Chemical protection: Provides an optimal chemical environment for accurate neuronal signalling. Ionic composition to be maintained in homeostasis as even slight changes in them can affect the production of action potentials and postsynaptic potentials. 3. Circulation: CSF is a medium for exchange of nutrients and waste products between the blood and nervous tissue. FUNCTIONS OF CSF Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 26. Meninges 26 • The meninges • Membranes of CNS • Protect the CNS • Three (3) layers: • Dura mater • “Tough mother” • Venous sinuses • Falx • Arachnoid mater • “Spiderweb-like” • Space contains cerebrospinal fluid (CSF) • Pia mater • “Faithful mother” • Encapsulates blood vessels Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Scalp Cranium Cerebrum Cerebellum Spinal cord Meninges Meninges Cerebrum (b)(a) Gray matter White matter Subarachnoid space Falx cerebri Pia mater Dura mater Bone of skull Subcutaneous tissue Skin Tentorium cerebelli Vertebra Dural sinus Arachnoid granulation Arachnoid mater Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 27. 27 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 28. 28 Protective covering of the brain: The cranium and the cranial meninges surround and protect the brain. The cranial meninges are continuous with spinal meninges. They are: 1. The outer dura mater (The cranial dura mater has 2 layers and spinal dura mater has only one). 2. The middle arachnoid mater and 3. The inner pia mater. The space between dura mater and arachnoid mater is known as subdural space and that between arachnoid mater and pia mater is knows as subarachnoid space which is filled with cerebrospinal fluid (CSF). Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 29. 29 The parts of brain are separated by 3 extensions of the dura mater. They are: 1. The falx cerebri which separate 2 hemispheres of cerebrum. 2. The falx cerebelli which seprate 2 hemispheres of cerebellum and 3. The tentorium cerebelli which separates the cerebrum from the cerebellum. Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 30. 30 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 31. Meninges of the Spinal Cord 31 Spinal cord Spinal cord Pia mater Arachnoid mater Dura mater Dorsal root Dorsal root Spinal nerve Epidural space (a) (b) Ventral root Dorsal root ganglion Thoracic vertebra Spinal nerve Dorsal root ganglion Subarachnoid space Dorsal branch (dorsal ramus) Ventral branch (ventral ramus) Ventral root Epidural space Body of vertebra Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 32. Major Parts of the Brain 32 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 33. STRUCTURE OF CEREBRUM. 33 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 34. Structure of the Cerebrum 34 • Corpus callosum • Connects cerebral hemispheres (a commissure) • Gyri • Bumps or convolutions • Sulci • Grooves in gray matter • Central sulcus • Fissures • Longitudinal: separates the cerebral hemispheres • Transverse: separates cerebrum from cerebellum • Lateral fissure (sulcus) of Sylvius Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Central sulcus Gyrus Sulcus Frontal lobe Lateral fissure of sylvius Parietal lobe Occipital lobe Central sulcus Parietal lobe Occipital lobe (a) (b) (c) Parietal lobe Central sulcus Occipital lobeFrontal lobe Insula Temporal lobe Longitudinal fissure Transverse fissure Cerebellar hemisphere Retracted temporal lobe Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 35. Lobes of the Cerebrum 35 • Five (5) lobes bilaterally: • Frontal lobe • Parietal lobe • Temporal lobe • Occipital lobe • Insula aka „Island of Reil‟ Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. (c) Parietal lobe Central sulcus Occipital lobe Frontal lobe Insula Retracted temporal lobe Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 36. 36 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 37. 37 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 38. Functions of the Cerebral Lobes 38 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 39. Functional Regions of the Cerebral Cortex 39 • Cerebral cortex • Thin layer of gray matter that constitutes the outermost portion of cerebrum • Contains 75% of all neurons in the nervous system Frontal eye field Central sulcus Parietal lobe Occipital lobe Cerebellum Brainstem Interpretation of auditory patterns Lateral sulcus Auditory area Sensory areas involved with cutaneous and other senses Sensory speech area ( Wernicke’s area) Combining visual images, visual recognition of objects Visual area Temporal lobe Motor speech area (Broca’s area) Motor areas involved with the control of voluntary muscles Concentration, planning, problem solving Front lobe Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 40. Motor Areas (pre-central sulcus) 40 Frontal eye field Central sulcus Parietal lobe Occipital lobe Cerebellum Brainstem Interpretation of auditory patterns Lateral sulcus Auditory area Sensory areas involved with cutaneous and other senses Sensory speech area ( Wernicke’s area) Combining visual images, visual recognition of objects Visual area Temporal lobe Motor speech area (Broca’s area) Motor areas involved with the control of voluntary muscles Concentration, planning, problem solving Front lobe • Primary motor areas • Frontal lobes • Control voluntary muscles • Broca‟s area • Anterior to primary motor cortex • Usually in left hemisphere • Controls muscles needed for speech • Frontal eye field • Above Broca‟s area • Controls voluntary movements of eyes and eyelids Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 41. Motor Areas 41 Parietal lobe Sensory area Central sulcus Motor area Frontal lobe Swallowing Forearm Arm Pelvis Thigh Leg Lips Forearm Arm Neck Pelvis Thigh Leg Genitals (a) Motor area (b) Sensory area Longitudinal fissure Salivation Vocalization Mastication Facial expression Thumb, fingers, and hand Trunk Foot and toes Tongue and pharynx Teeth and gums Upper face Hand, fingers, and thumb Trunk Foot and toes Longitudinal fissure Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 42. Sensory Areas (post-central sulcus) 42 • Cutaneous sensory area • Parietal lobe • Interprets sensations on skin • Visual area • Occipital lobe • Interprets vision • Auditory area • Temporal lobe • Interprets hearing • Sensory area for taste • Near base of the central sulcus • Sensory area for smell • Arises from centers deep within the cerebrum Frontal eye field Central sulcus Parietal lobe Occipital lobe Cerebellum Brainstem Interpretation of auditory patterns Lateral sulcus Auditory area Sensory areas involved with cutaneous and other senses Sensory speech area ( Wernicke’s area) Combining visual images, visual recognition of objects Visual area Temporal lobe Motor speech area (Broca’s area) Motor areas involved with the control of voluntary muscles Concentration, planning, problem solving Front lobe Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 43. Sensory Areas 43 Parietal lobe Sensory area Central sulcus Motor area Frontal lobe Swallowing Forearm Arm Pelvis Thigh Leg Lips Forearm Arm Neck Pelvis Thigh Leg Genitals (a) Motor area (b) Sensory area Longitudinal fissure Salivation Vocalization Mastication Facial expression Thumb, fingers, and hand Trunk Foot and toes Tongue and pharynx Teeth and gums Upper face Hand, fingers, and thumb Trunk Foot and toes Longitudinal fissure Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 44. Association Areas 44 • Regions that are not primary motor or primary sensory areas • Widespread throughout the cerebral cortex • Analyze and interpret sensory experiences • Provide memory, reasoning, verbalization, judgment, emotions Frontal eye field Central sulcus Parietal lobe Occipital lobe Cerebellum Brainstem Interpretation of auditory patterns Lateral sulcus Auditory area Sensory areas involved with cutaneous and other senses Sensory speech area ( Wernicke’s area) Combining visual images, visual recognition of objects Visual area Temporal lobe Motor speech area (Broca’s area) Motor areas involved with the control of voluntary muscles Concentration, planning, problem solving Front lobe Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 45. Association Areas 45 • Frontal lobe association areas • Concentrating • Planning • Complex problem solving • Parietal lobe association areas • Understanding speech • Choosing words to express thought • Temporal lobe association areas • Interpret complex sensory experiences • Store memories of visual scenes, music, and complex patterns • Occipital lobe association areas • Analyze and combine visual images with other sensory experiences Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 46. Hemisphere Dominance 46 • The left hemisphere is dominant in most individuals • Dominant hemisphere controls: • Speech • Writing • Reading • Verbal skills • Analytical skills • Computational skills • Nondominant hemisphere controls: • Nonverbal tasks • Motor tasks • Understanding and interpreting musical and visual patterns • Provides emotional and intuitive thought processes Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 47. Memory 47 • Short term memory • Working memory • Closed neuronal circuit • Circuit is stimulated over and over • When impulse flow ceases, memory does also unless it enters long-term memory via memory consolidation • Long term memory • Changes structure or function of neurons • Enhances synaptic transmission Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 48. FUNCTIONS OF CEREBRUM. 48 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 49. Functions of the Cerebrum 49 • Interpreting impulses • Initiating voluntary movements • Storing information as memory • Retrieving stored information • Reasoning • Seat of intelligence and personality Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 50. STRUCTURE OF BASAL NUCLEI 50 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 51. Basal Nuclei /Basal Ganglia 51 • Masses of gray matter • Deep within cerebral hemispheres • Caudate nucleus, putamen, and globus pallidus • Produce dopamine • Control certain muscular activities • Primarily by inhibiting motor functions Thalamus Hypothalamus Brainstem Putamen Cerebellum Spinal cord Longitudinal fissure Right cerebral hemisphere Caudate nucleus Globus pallidus Basal nuclei Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 52. STRUCTURE OF DIENCEPHALON 52 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 53. Diencephalon 53 • Between cerebral hemispheres and above the brainstem • Surrounds the third ventricle • Thalamus • Epithalamus • Hypothalamus • Optic tracts • Optic chiasm • Infundibulum • Posterior pituitary • Mammillary bodies • Pineal gland Pyramidal tract Pons Optic nerve Optic chiasma Thalamus Spinal cord Pituitary gland Pineal gland Optic tract Mammillary body (a) (b) Olive Corpora quadrigemina Cerebral peduncles Superior colliculus Inferior colliculus Third ventricle Fourth ventricle Cerebellar peduncles Medulla oblongata Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 54. Diencephalon 54 • Thalamus • Gateway for sensory impulses heading to cerebral cortex • Receives all sensory impulses (except smell) • Channels impulses to appropriate part of cerebral cortex for interpretation • Hypothalamus • Maintains homeostasis by regulating visceral activities • Links nervous and endocrine systems (hence some say the neuroendocrine system Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 55. Diencephalon 55 • Consists of: • Portions of frontal lobe • Portions of temporal lobe • Hypothalamus • Thalamus • Basal nuclei • Other deep nuclei • Functions: • Controls emotions • Produces feelings • Interprets sensory impulses The Limbic System Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 56. 56 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA. Functions of the Diencephalon.
  • 57. THE STRUCTURE OF BRAIN STEM 57 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 58. Brainstem 58 Three parts: 1. Medulla Oblongata 2. Pons 3. Midbrain Spinal cord Thalamus Hypothalamus Diencephalon Pons Midbrain Corpus callosum Corpora quadrigemina Cerebral aqueduct Reticular formation Medulla oblongata Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 59. Medulla Oblongata 59 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Pyramidal tract Pons Optic nerve Optic chiasma Thalamus Spinal cord Pituitary gland Pineal gland Optic tract Mammillary body (a) (b) Olive Corpora quadrigemina Cerebral peduncles Superior colliculus Inferior colliculus Third ventricle Fourth ventricle Cerebellar peduncles Medulla oblongata • Enlarged continuation of spinal cord • Conducts ascending and descending impulses between brain and spinal cord • Contains cardiac, vasomotor, and respiratory control centers • Contains various nonvital reflex control centers (coughing, sneezing, swallowing, and vomiting) Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 60. 60 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 61. Pons 61 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Pyramidal tract Pons Optic nerve Optic chiasma Thalamus Spinal cord Pituitary gland Pineal gland Optic tract Mammillary body (a) (b) Olive Corpora quadrigemina Cerebral peduncles Superior colliculus Inferior colliculus Third ventricle Fourth ventricle Cerebellar peduncles Medulla oblongata • Rounded bulge on underside of brainstem • Between medulla oblongata and midbrain • Helps regulate rate and depth of breathing • Relays nerve impulses to and from medulla oblongata and cerebellum Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 62. Midbrain 62 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Pyramidal tract Pons Optic nerve Optic chiasma Thalamus Spinal cord Pituitary gland Pineal gland Optic tract Mammillary body (a) (b) Olive Corpora quadrigemina Cerebral peduncles Superior colliculus Inferior colliculus Third ventricle Fourth ventricle Cerebellar peduncles Medulla oblongata • Between diencephalon and pons • Contains bundles of fibers that join lower parts of brainstem and spinal cord with higher part of brain • Cerebral aqueduct • Cerebral peduncles (bundles of nerve fibers) • Corpora quadrigemina (centers for visual and auditory reflexes) Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 63. 63 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 64. 64 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 65. FUNCTIONS OF VITAL CENTERS OF MEDULLA OBLONGATA 65 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 66. 66 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 67. 67 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 68. Reticular Formation 68 • Complex network of nerve fibers scattered throughout the brain stem • Extends into the diencephalon • Connects to centers of hypothalamus, basal nuclei, cerebellum, and cerebrum • Filters incoming sensory information • Arouses cerebral cortex into state of wakefulness Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Spinal cord Thalamus Hypothalamus Diencephalon Pons Midbrain Corpus callosum Corpora quadrigemina Cerebral aqueduct Reticular formation Medulla oblongata Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 69. Types of Sleep 69 • Slow wave • Non-REM sleep • Person is tired • Decreasing activity of reticular system • Restful • Dreamless • Reduced blood pressure and respiratory rate • Ranges from light to heavy • Alternates with REM sleep • Rapid Eye Movement (REM) • Paradoxical sleep • Some areas of brain active • Heart and respiratory rates irregular • Dreaming occurs Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 70. STRUCTURE OF CEREBELLUM 70 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 71. Cerebellum 71 • Inferior to occipital lobes • Posterior to pons and medulla oblongata • Two hemispheres • Vermis connects hemispheres • Cerebellar cortex (gray matter) • Arbor vitae (white matter) • Cerebellar peduncles (nerve fiber tracts) • Dentate nucleus (largest nucleus in cerebellum) • Integrates sensory information concerning position of body parts • Coordinates skeletal muscle activity • Maintains posture Thalamus Superior peduncle Middle peduncle Inferior peduncle Pons Medulla oblongata Cerebellum Corpus callosum Longitudinal fissure Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 72. 72 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 73. FUNCTIONS OF CEREBELLUM. 73 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 74. 74 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 75. STRUCTURE AND FUNCTION OF SPINAL CORD. 75 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 76. Spinal Cord 76 • Slender column of nervous tissue continuous with brain and brainstem • Extends downward through vertebral canal • Begins at the foramen magnum and terminates at the first and second lumbar vertebrae (L1/L2) interspace Brainstem Spinal cord (a) (b) Foramen magnum Cervical enlargement Vertebral canal Lumbar enlargement Conus medullaris Cauda equina Filum terminale Conus medullaris Lumbar enlargement Cervical enlargement Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 77. Structure of the Spinal Cord 77 White matter Gray matter Lateral funiculus Posterior funiculus Gray commissure Central canal (a) Posterior horn Dorsal root of spinal nerve Dorsal root ganglion Ventral root of spinal nerve Anterior horn Anterior median fissure Portion of spinal nerve Anterior funiculus Posterior median sulcus Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 78. Tracts of the Spinal Cord 78 • Ascending tracts conduct sensory impulses to the brain • Descending tracts conduct motor impulses from the brain to motor neurons reaching muscles and glands Posterior spinocerebellar tract Lateral corticospinal tract Lateral reticulospinal tract Rubrospinal tract Anterior spinocerebellar tract Lateral spinothalamic tract Anterior reticulospinal tract Medial reticulospinal tract Fasciculus cuneatus Fasciculus gracilis Dorsal column Anterior spinothalamic tract Anterolateral system Anterior corticospinal tract Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 79. Ascending Tracts 79 • Major ascending (sensory) spinal cord tracts: • Fasciculus gracilis and fasciculus cuneatus • Spinothalamic tracts • Lateral and anterior • Spinocerebellar tracts • Posterior and anterior Midbrain Pons Medulla Thalamus Sensory cortex of cerebrum Cerebrum (frontal section) Brainstem (transverse sections) Spinal cord (transverse section) Sensory fibers cross over Spinothalamic tract Fasciculus Cuneatus tract Sensory impulse from skin temperature or pain receptors Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 80. Descending Tracts 80 • Major descending (motor) spinal cord tracts: • Corticospinal tracts • Lateral and anterior • Reticulospinal tracts • Lateral, anterior and medial • Rubrospinal tract Midbrain Pons Brainstem (transverse sections) Spinal cord (transverse section) Motor cortex of cerebrum Cerebrum (frontal section) Corticospinal tract Medulla oblongata Motor fibers cross over Motor impulse to Skeletal muscle Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 81. Nerve Tracts of the Spinal Cord 81 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 82. Functions of Spinal Cord 82 • Center for spinal reflexes • Conduit (pathway) for nerve impulses to and from the brain and brainstem Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 83. Reflex Arcs 83 • Reflexes are automatic, subconscious responses to stimuli within or outside the body • Simple reflex arc (sensory – motor) • Most common reflex arc (sensory – association – motor) Receptor (a) Sensory or afferent neuron Motor or efferent neuron Central Nervous System Effector (muscle or gland) Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 84. Reflex Arcs 84 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 85. General Components of a Spinal Reflex 85 Receptor Sensory neuron Motor neuron White matter Gray matter Spinal cord DorsalInterneuron 4 5 3 2 1 (b) Cell body of sensory neuron Effector (muscle or gland) Central canal Ventral Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 86. Reflex Behavior 86 • Example is the knee-jerk reflex • Simple monosynaptic reflex • Helps maintain an upright postureCopyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Spinal cord Patella Patellar ligamentDirection of impulse Axon of sensory neuron Cell body of sensory neuron Cell body of motor neuron Axon of motor neuron Effector (quadriceps femoris muscle group) Receptor associated with dendrites of sensory neuron Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 87. Reflex Behavior 87 • Example is a withdrawal reflex (flexor reflex) • Prevents or limits tissue damage Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Interneuron Spinal cord Axon of sensory neuron Cell body of sensory neuron Dendrite of sensory neuron Pain receptor in skin Direction of impulse Cell body of motor neuron Axon of motor neuron Effector (flexor muscle contracts and withdraws part being stimulated) Tack Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 88. Reflex Arc 88 • Example crossed extensor reflex • Crossing of sensory impulses within the reflex center to produce an opposite effect Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. =Stimulation = Inhibition Interneuron Flexor contracts Sensory neuron + + + – – – Motor neurons Extensor contracts Flexor relaxes Motor neurons Extensor relaxes Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 89. 89 Wednesday, April 02, 2014ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.
  • 90. Wednesday, April 02, 2014 90 ST.JOSEPH’S COLLEGE OF PHARMACY, CHERTHALA.