Chapter 2

• What is the basic structure of the brain?

  • brain has structure BUT is not a static organ; we are not born with a brain that remains unchanged for the rest of our lives
  • brain is a plastic organ; neural tissue has the ability to adapt to the world --> neural plasticity (example: learning)
• Navigating the brain- different orientation systems

  Brain-Body orientation: illustrates brain structure location from the frame of reference of the human face

  
• Navigating the brain- different orientation systems

  Spatial Orientation: illustrates brain structure location in relation to other body parts and body orientation

  
• Navigating the brain- different orientation systems

  Anatomic Orientation: illustrates the direction of a cut or section through the human brain from the perspective of a viewer

  
• Brain protection- meninges & cerebrospinal fluid (CSF)

  
• Blood supply for the brain- different views

  
• Cerebrovascular accident (CVA, ‘stroke’)

  Ischemic CVA (80%) = blockage of blood vessel by clot

  
• Cerebrovascular accident (CVA, ‘stroke’)

  Hemorrhagic CVA (20%) = Burst of vessel bleeding into the brain

  
• What are the main structures of the brain visible from the outside?

  1. Cerebrum
  2. Cerebellum ('little cerebrum')
  3. Brainstem

  
• The Cerebral Cortex – the brain’s outer “bark” layer

  
• Inside the brain - What is gray and white matter?

  Gray matter: nerve cells (no insulating layer)

  White matter: nerve fibers (insulating layer, fatty myelin)

  
• What is the ventricle system?

  4 interconnected cavities filled with cerebrospinal fluid (CSF)

  1st and 2nd = lateral ventricles -> one in each hemisphere

  Third ventricle -> diencephalon; between right and left thalamus

  Fourth ventricle -> between the cerebellum and the pons

  
• What is the presumed function of the ventricle system?

  maintaining brain metabolism, excretion of metabolic waste, cushion the brain
• How can we organise the human nervous system?

  1. Anatomica Organisation
  2. Functional Organisation
• Central and peripheral nervous system - image

  
• Anatomic organisation of the human nervous system

  
• Functional organisation of the human nervous system

  
• Ontogenetic organization of the human nervous system (evolution of brain development)

  
• In Brain and Behavior, we discuss brain anatomy from the bottom up: 1. Spinal cord 2. Brainstem 3. Forebrain

  !! The higher a structure is located physically, the ‘higher’ its function. (higher in sense of more complex, more integrated)
• Spinal cord, Brainstem, Forebrain

  
• Brain tissue consists of 2 types of nerve cells. What are the types?

  • Neurons: major brain functions
  • glial cells: support cells (lit.glue)
• What do Neurons look like and how are they also called?

  --> pyramidal cell

  
• What do glial cells look like & what are they?

  --> astrocyte

  
• Through what are cells connected?

  Nerve fibers (axons)
• What is a bundle of nerve fibers called?

  • tract (within the CNS)
  • nerve (outside of the CNS)

  
• The spinal cord (part of CNS)- image

  
• What is the matter inside the spinal cord?

  gray matter --> nerve cells

  contrary to brain tissue, there: gray matter = outside
• What is on the outer side of the spinal cord?

  white matter --> nerve fibers (tracts)

  contrary to brain tissue: there, white matter = inside
• What does a herniated disk (of the spinal cord) looks like comapred to normal anatomy?

  Herniated disk: compressed spinal nerve

  
• What are the 5 spinal cord segments?

  1. Cervical
  2. Thoracic
  3. Lumbar
  4. Sacral
  5. Coccygeal
• What is a dermatome?

  body segment
• each dermatome (body segment) has two spinal (peripheral) nerves. What are they?

  a sensory nerve (afferent) to send information from skin, joints, and muscles to the spinal cord

  a motor nerve (efferent) to control muscle movements in that particular body segment
• What is the functional organisation of the spinal nerves?

  image:

  
• How are the spinal cord segments arranged along the spinal cord?

  image-left side

  
• Directional flow of neural information -Afferent:

  towards a structure (“input”)

  --> Sensory pathways are afferent (incoming)
• Directional flow of neural information- Efferent:

  away from a structure (“output”)

  Motor pathways are efferent (outgoing)
• What is the order of the directional flow of neural information?

  First input, then output

  First afferent, then efferent

  Mnemonics:

  First a then e (alphabetically)

  a = arriving = afferent

  e = exit = efferent
• How does the directional flow of neural information look like?

  image:

  
• Spinal nerves – Law of Bell and Magendie: How does it look like-step by step?

  !! spinal nerves are located on the left and right side of the spinal cord (bilateral pairs)

  here: only right side of spinal cord shown

  
• Spinal nerves – Law of Bell and Magendie: What does the dorsal/ posterior root do or what is it responsible for?

  • sensory (afferent)
  • pain, temperature, touch