Neurons

• What are neurons?


  Specialised cells that conduct electrical impulses through the body
• What are the three types of neurons mentioned?

  • Sensory Neuron
  • Motor Neuron
  • Relay Neuron
• What is the function of sensory neurons?


  They transmit messages from sense receptors to the brain or spinal cord
• What do motor neurons do?


  They transmit messages from the brain and spinal cord to the muscles and glands
• What is the role of relay neurons?


  They allow sensory and motor neurons to communicate with each other
• Where do relay neurons lie?


  Wholly within the brain and spinal cord
• What is synaptic transmission?


  • How neurons communicate with one another
  • Involves transmitting chemicals called neurotransmitters
  • Occurs across a small gap called the synaptic cleft
• What happens when one neuron wants to send a signal to another?


  It transmits neurotransmitters into the synaptic cleft
• What do neurotransmitters do in synaptic transmission?


  They travel across the gap and bind to the receiving neuron
• What are excitatory neurotransmitters?


  They increase the likelihood that an electrical impulse will be triggered in the postsynaptic neuron
• What are inhibitory neurotransmitters?


  They decrease the likelihood that an electrical impulse will be triggered in the postsynaptic neuron
• How do antidepressants affect neurotransmitters in a synapse?


  • They increase levels of certain neurotransmitters (like serotonin)
  • They block the reabsorption (or reuptake) of neurotransmitters
  • They make more neurotransmitters available in the synapse
• What is the effect of antidepressants on mood?


  They help improve mood and reduce symptoms of depression
• How do antidepressants facilitate signal transmission between neurons?


  By increasing neurotransmitter availability in the synapse