Biopsyc exam 1

• The nervous system consists of two parts, the central nervous system (CNS) and peripheral nervous system (PNS).
• The PNS is divided into somatic and autonomic divisions.
• The three types of neurons are...

  sensory, motor, interneurons
• Dendrites do what?

  Detect signals
• Axon hillock is the trigger zone


  It starts a signal within the cell
• Terminals are the end goal


  They release neurotransmitters
• The membrane has selective permeability

  • Channels/pumps (ions)
• Leak, voltage or ligand-gated

  • Leak-gated is just always open
  • Voltage-gated only opens up if a certain voltage is reached
  • Ligand-gated only opens up if a ligand binds to it
• The 4 major ions are..

  1. Na+ → Sodium
  2. K+ → Potassium
  3. Cl- → Chloride
  4. Ca+ → Calcium
• Resting potential

  -70 mV
• What is action potential?

  • Neurons firing
  • -55 mV
• Action potential steps

  1. Presynaptic neurons release neurotransmitter, which binds to receptors on postsynaptic neuron
  2. Na+ enters through ligand-gated channels on dendrites
  3. @ -55mv → Voltage-gated Na+ channels open at axon hillock allowing Na+ inside
  4. @ +40mv → Na+ channel closes, voltage-gated K+ channels open so K+ can leave cell
  5. Lots of K+ leaves the cell causing a refractory period
  6. Return to resting state
• Glial cells

  Support

  • Myelin - Insulates neurons
  • Schwan cells (PNS)
  • Oligodendrocyte
  • Microglial cell - Eat everything (i.e. neurons that have died)
  • Ependymal cells - Produce a specific fluid in your nervous system (cerebral spinal fluid; CSF)
  • Astrocyte - Deliver nutrients to cells
• Myelin:

  • Gaps
  • Nodes of Ranvier
  • 1000th of mm
  • Faster signaling
• The synapse:

  • Connection between neurons
  • Gaps
  • Neurotransmitters
• Graded potentials:

  • Type of incoming signal
  • EPSP → Excitatory post synaptic potential
  • Move closer to threshold level
  • Sodium comes in!
  • IPSP → Inhibitory post synaptic potential
  • Moves further away from threshold level
  • Chloride comes in!!
• What are the two types of summation?

  1. Spatial summation
  2. Signal from different locations
  3. 2. Temporal summation
  4. B. Signal coming from short time apart
• What are the 4 lobes of the forebrain? What do they do?

  1. Frontal: decision-making, spoken language, motor, personality
  2. Temporal: Auditory
  3. Parietal: Touch / Proprioception: Know where you are compared to space even with eyes closed
  4. Occipital: Visual
• What are the two parts of the autonomic system?

  1. Parasympathetic
  2. Rest & digest
  3. 2. Sympathetic
  4. Fight or flight
• Somatic system:

  • Sensation
  • Motor
  • Voluntary
• What is biopsychology?

  Studies how the brain and nervous system influence human behavior
• What are the 3 brain imaging techniques?

  1. MRI: Structure of the brain
  2. fMRI: Function of the brain
  3. EEG: Electrical activity
• Descartes

  • Hydraulic model
  • Fluid made up of animal spirits
• Camillo Golgi

  • Staining: Highlights cells; turning them black
  • Allowed for evidence of neuron doctrine
  • Neuron doctrine: belief that our nervous system isn’t just one long strand of cells but maybe it’s composed of discrete, independent cells that communicate with each other
• Franz Gall

  • Phrenology: Shape of your skull can indicate certain things about you and your behavior
• What is localization?

  Certain areas of the brain carry out specific information
• Karl Lashley

  • Equipotentiality: All areas of the brain are equally able to perform a task