Chapter 04: Anatomy of the Nervous System


Published on

The construction of the Central Nervous System and the Brain.

  • Be the first to comment

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide

Chapter 04: Anatomy of the Nervous System

  1. 1. Anatomy of the Nervous System
  2. 2. Categories of Brain Research <ul><li>Examining the Effects of Brain Damage </li></ul><ul><li>Examining the Effects of Stimulating Some Part of the Brain </li></ul><ul><li>Recording What Happens in the Brain During Some Kind of Behavior </li></ul><ul><li>Correlating Brain Anatomy with Behavior </li></ul>
  3. 3. Effects of Brain Damage <ul><li>Broca Discovered An Area Associated with Speech Production </li></ul><ul><li>No 2 People Have the Same Kind of Damage </li></ul><ul><li>Methods: </li></ul><ul><li>Working with Brain Damaged People </li></ul><ul><li>Temporarily inactivating part of the brain & studying behavior </li></ul><ul><li>Implanting electrodes into animal brains or injecting chemicals </li></ul>
  4. 4. Effects of Brain Stimulation <ul><li>With Animals, Electrodes can be Implanted </li></ul><ul><li>With Humans, Magnetic Fields on the Scalp will Stimulate </li></ul><ul><li>Stimulation can also be caused by Injecting a Chemical that Stimulates a Particular Receptor </li></ul>
  5. 5. Recording Brain Activity <ul><li>Positron Emission Tomography (PET) </li></ul><ul><li>Regional Cerebral Blood Flow (rCBF) </li></ul><ul><li>Functional Magnetic Resonance Imagery (fMRI) </li></ul><ul><li>Problem with non-invasive methods is interpreting the images </li></ul>
  6. 6. The Organization of the Nervous System Nervous System Central Nervous System (Processes, interprets & Stores information; issues Orders to muscles, Glands, organs) Peripheral Nervous System (Transmits information to & from the CNS) Brain Spinal Cord ( Bridge between the brain & peripheral nerves) Somatic Nervous System (Controls skeletal muscles) Autonomic Nervous System (Regulates glands, blood Vessels, & internal organs) Sympathetic Nervous System (Mobilizes body for action, Energy output) Parasympathetic Nervous System (Conserves energy, Maintains quiet state)
  7. 7. Anatomical Terms <ul><li>Dorsal Ventral Anterior </li></ul><ul><li>Posterior Superior Inferior </li></ul><ul><li>Lateral Medial Proximal </li></ul><ul><li>Distal Ipsilateral Contralateral </li></ul><ul><li>Coronal Plane Saggital Plane Horizontal Plane </li></ul><ul><li>Lamina Column Tract </li></ul><ul><li>Nerve Ganglion Gyrus </li></ul><ul><li>Sulcus Fissure </li></ul>
  8. 8. The Spinal Cord <ul><li>Part of the CNS </li></ul><ul><li>Communicates with the sense organs & muscle below the level of the head </li></ul><ul><li>Sends & receives sensory information to the brain & receives commands from the head </li></ul><ul><li>Bell-Magendie Law </li></ul><ul><li>Dorsal roots enter the spinal cord carrying information from the sensory organs </li></ul><ul><li>Ventral roots exit the spinal cord carrying motor information to the muscles & glands </li></ul><ul><li>Dorsal Root Ganglia </li></ul><ul><li>Gray Matter </li></ul><ul><li>White Matter </li></ul>
  9. 9. Autonomic Nervous System <ul><li>2 Divisions: </li></ul><ul><li>Sympathetic Nervous System </li></ul><ul><li>“ Fight-or-flight” system that prepares the body for action </li></ul><ul><li>Parasympathetic Nervous System </li></ul><ul><li>Brings the body back to normal after an emergency </li></ul><ul><li>Also known as Craniosacral System because it consists of cranial nerves & nerves from the sacral spinal cord </li></ul>
  10. 10. The Brain
  11. 12. 1 st Major Division <ul><li>Hindbrain </li></ul><ul><li>Medulla, Pons, Reticular Formation & Cerebellum </li></ul><ul><li>Medulla controls breathing, heart rate, vomiting, coughing & other vital reflexes through the cranial nerves </li></ul><ul><li>Pons job is sensorimotor control and with the medulla deals with blood pressure, temperature, heart rate, and breathing </li></ul><ul><li>Cerebellum controls speech production, learning skills, walking, unconscious movements, & coordinates reflexes </li></ul><ul><li>Reticular Formation is involved in alertness, sleep & wakefulness, & is a censor of incoming information </li></ul>
  12. 13. 2 nd Major Division <ul><li>Midbrain </li></ul><ul><li>Tectum, Tegmentum & the Substantia Nigra </li></ul><ul><li>Tectum is made up of the Superior & Inferior Colliculus, both involved in processing sensory information </li></ul><ul><li>Tegmentum includes part of the Reticular Formation, part of the Substantia Nigra & the Red Nucleus which processes rewarding stimuli & sensorimotor control </li></ul><ul><li>Substantia Nigra contains dopamine neurons in the reward circuit & which deteriorate in Parkinson’s </li></ul>
  13. 14. 3 rd Major Division <ul><li>Forebrain </li></ul><ul><li>Cerebral Cortex & several Subcortical Areas </li></ul><ul><li>Limbic System consists of the Thalamus, Hypothalamus, Amygdala, Hippocampus & Olfactory Bulbs </li></ul><ul><li>Basal Forebrain includes the Nucleus Basalis & is key in arousal </li></ul><ul><li>Basal Ganglia includes the Caudate, Putamen, & Globus Pallidus & deterioriates in Parkinson’s & Huntington’s Diseases </li></ul><ul><li>Pituitary Gland is an endocrine gland that is involved secreting vasopressin and oxytocin </li></ul>
  14. 15. The Ventricles <ul><li>Central Canal </li></ul><ul><li>Fluid-filled channel in the center of the spinal cord </li></ul><ul><li>Cerebrospinal Fluid </li></ul><ul><li>Clear fluid found in the ventricles & central canal formed by the choroid plexus cells in the ventricles </li></ul><ul><li>Meninges </li></ul><ul><li>Thin membranes surrounding the brain & spinal cord </li></ul><ul><li>Hydrocephalus </li></ul><ul><li>Obstruction & accumulation of CSF in the ventricles or subarachnoid space </li></ul>
  15. 16. Cerebral Cortex <ul><li>Consists of the 2 Hemispheres </li></ul><ul><li>Divided into 4 Lobes </li></ul><ul><li>Occipital </li></ul><ul><li>Parietal </li></ul><ul><li>Temporal </li></ul><ul><li>Frontal </li></ul>
  16. 17. Forebrain <ul><li>Each Hemisphere Receives Contralateral Sensory Information & Controls Contralateral Motor Movement </li></ul><ul><li>Cerebral Cortex is the Cellular Layers on the Outer Surface of the Cerebral Hemispheres </li></ul>
  17. 18. Organization of the Cerebral Cortex <ul><li>Laminae </li></ul><ul><li>Up to 6 distinct Laminae or layers </li></ul><ul><li>Columns </li></ul><ul><li>Cells in Cerebral Cortex also arranged in Columns </li></ul><ul><li>Columns lie perpendicular to Laminae </li></ul>
  18. 19. Hemispheric Communications <ul><li>Corpus Callosum </li></ul><ul><li>Main communications route between the hemispheres </li></ul><ul><li>Anterior Commissure </li></ul><ul><li>2 nd bundle of axons that allows communications between the hemispheres </li></ul>>
  19. 20. Lobes of the Brain <ul><li>Occipital Lobe </li></ul><ul><li>Part of the visual pathway system </li></ul><ul><li>The Primary Visual Cortex (Striate Cortex) is the most posterior of the Occipital Lobe </li></ul><ul><li>Destruction of any part of the Striate Cortex produces cortical blindness </li></ul><
  20. 21. Lobes of the Brain <ul><li>Parietal Lobe </li></ul><ul><li>Between the Occipital Lobe and the Central Sulcus </li></ul><ul><li>Primary target for touch sensations & information from muscle-stretch receptors & joint receptors </li></ul><ul><li>Monitors all information about the eye, head, & body positions as it passes it on to the brain areas that control movement </li></ul>^
  21. 22. Lobes of the Brain <ul><li>Temporal Lobe </li></ul><ul><li>Primary target for auditory information </li></ul><ul><li>In humans, involved in the comprehension of spoken language & contributes to complex aspects of vision, including facial recognition & perception of movement </li></ul><ul><li>Kluver-Bucy Syndrome: after temporal lobe damage, lack of fear or anxiety responding </li></ul><
  22. 23. Lobes of the Brain <ul><li>Frontal Lobe </li></ul><ul><li>Contains the Primary Motor Cortex & Prefrontal Cortex </li></ul><ul><li>Precentral Gyrus (Primary Motor Cortex) is specialized for fine motor movements, primarily on the contralateral side of the body </li></ul><ul><li>Prefrontal Cortex forms a large part of the brain </li></ul><ul><li>It receives information from all the senses </li></ul>>
  23. 24. Lobes of the Brain <ul><li>Viewing Prefrontal Functions </li></ul><ul><li>Important in Working Memory </li></ul><ul><li>Damage to Prefrontal Cortex affects time-delayed memory tasks </li></ul><ul><li>Important for Context-Dependent Behaviors (State Dependent vs. Context Dependent) </li></ul>
  24. 25. Prefrontal Lobotomy <ul><li>Pretty Much Abandoned at Present </li></ul><ul><li>Prefrontal damage produces loss of social inhibitions & impulsive acting out </li></ul><ul><li>Disconnecting the prefrontal cortex from most of the brain to control psychological disorders </li></ul><ul><li>Usually resulted in loss of the ability to plan, take initiative, memory disorders, distractibility, & loss of emotional expression </li></ul><ul><li>Today, drugs are in use </li></ul>
  25. 26. The Binding Problem <ul><li>How do Visual, Auditory, & other areas of the brain influence one another to produce a combined perception of a single object? </li></ul><ul><li>Early on, it was thought the Association Areas were used for processing & linking information from several sensory modalities </li></ul><ul><li>Binding may depend on simultaneous activity in various areas of the brain </li></ul>