Synaptic Transmission

• Neurotransmitters


  Chemical messengers either excitatory (stimulate) or inhibitory (make less likely) to develop action potential
• Process of Synaptic Transmission:

  • AP travels down axon, stimulating vesicles to merge with pre-synaptic membrane
  • Neurotransmitters are released into the cleft
  • Receptors on post-synaptic membrane attach with neurotransmitters changing tertiary structure of channel proteins
  • If threshold reaches, AP is formed
  • Neurotransmitters detach and return to pre-synapse through transport protein via reuptake
• Excitation


  Increased likelihood to reach AP, depolarising the post-synapse
• Inhibition


  Decreased likelihood of AP, hyperpolarising the post-synapse
• Summation


  Combined influences of neurotransmitters
• Uni-Directional


  AP only passed through Pre to Post