Mod 7

• 3 main parts of neurological system

  brain, spinal cord, cellular structures (cranial, spinal nerves)
• Central nervous system (CNS)


  Brain, spinal cord, automatic, involuntary, encased in bone
• Sympathetic


  Fight or flight
• Parasympathetic


  Counterbalances sympathetic, coming down from sympathetic
• Functions of nervous system

  • Perceive, discriminate sensory stimulus, express emotions, respiration, heartbeat, organizes, regulates behavior, thinking, remembering
• Types of nerves

  • Automatic, somatic
• Glial cells

  Support, protect nerve cells
• Types of glial cells


  • Astrocytes, oligodendroglia, ependymal, microglia
• Astrocytes


  Loosely woven, most widely distributed, fibroblasts produce fibers that are either excitatory (tell next neuron to fire) or inhibitory (stop next neuron from firing), structural matrix holds everything up
• Oligodendroglia


  Form myelin sheath
• Ependymal

  Create cerebral spinal fluid (CSF) to cushion brain
• Microglia


  Scavengers, cleaners, remove waste, help with immune response
• Neurons


  Basic functional unit of CNS, need a lot of support to do anything
• Axons


  • Long projections, often myelinated, go down to terminal bouton
• Terminal boutons


  Attach to a muscle/gland, act on it, excitatory or inhibitory
• Thicker myelin diameter


  Faster the axon
• Multipolar neuron


  Motor neurons activating muscles to move, has many dendrites coming off with one long axon, higher cognitive function
• Bipolar neuron


  Cell body with two poles, one pole is a single dendrite receiving information, the other is an axon coming off
• Interneurons

  Short, unmyelinated, faster
• Neurotransmitters


  Released from terminal boutons, cross synaptic cleft, bind to receptive site, cause next behavior on other side
• Hyperpolarization


  Next neuron won't fire, makes it super negative
• Depolarization


  Next neuron fires, makes it positive
• Excitation


  Creates glutamate in CNS, ach in PNS
• Inhibition

  Creates GABA
• Neurotransmitter release

  1. Presynaptic release

  2. Postsynaptic inactivation
• Chemical process


  1. Chemical enters neuron

  2. Changes its resting potential

  3. Depolarization of cell

  4. Gates open

  5. Na+ charge comes in

  6. Ca channels open

  7. Release neurotransmitter
• Cerebrum

  Higher level functions, sensorimotor integration, perception
• Basal ganglia

  Regulates efferent motor system, base of brain, inhibitory area, regulate muscle tone, ongoing movements, inhibits
• Thalamus

  biggest relay center for all sensory information
• Dura mater

  Most superficial, adheres to skull, spinal column all the way down to sacrum, tough mother, very strong
• Arachnoid

  Filled with CSF to cushion brain
• Pia mater


  Adheres to all nooks and crannies of brain, loving mother, very thin
• Meningitis

  Inflammation of brain, infection of meninges, swells, goes down on to the skull where all our higher cortical functions are
• Types of ventricles

  • Lateral, third, fourth
• Lateral ventricles

  Support two hemispheres
• Third ventricle

  Choroid plexus where CSF is produced
• Fourth ventricle

  Keeps brainstem and cerebellum cushioned from each other
• Cerebral spinal fluid (CSF)

  Regulation of intracranial pressure, cleanses, nourishes CNS, shock absorber, produced in choroid plexus, reabsorbed through venous system
• Brainstem

  Stores vegetative functions, heartbeat, digestion, swallowing, 3 parts: midbrain, pons, medulla oblongata
• Broca's area


  Can't speak after brain damage, expressive