Synaptic transmission

• What reaches the presynaptic terminal to initiate synaptic transmission?

  Electrical impulses (action potentials)
• What triggers the release of neurotransmitters at the presynaptic terminal?

  Electrical impulses (action potentials)
• Name a neurotransmitter that is released during synaptic transmission.

  Serotonin
• What happens to neurotransmitters after they are released into the synaptic cleft?

  They diffuse across the synaptic cleft
• What do neurotransmitters combine with on the postsynaptic membrane?

  Receptors
• What are the two possible outcomes of neurotransmitter stimulation on the postsynaptic membrane?

  Excitation (depolarisation) or inhibition (hyperpolarisation)
• Why can neurons only transmit information in one direction at a synapse?

  Because synaptic vesicles are only present on the presynaptic membrane
• What is the role of receptors in synaptic transmission?

  They enable the signal to be passed to the next neuron
• How do neurotransmitters diffuse across the synaptic cleft?

  From high to low concentration
• What is serotonin believed to help regulate?

  Mood and social behavior, appetite and digestion, sleep, memory, and sexual desire
• What mental health condition is linked to low levels of serotonin?

  Depression
• What does dopamine affect?

  Emotions, movements, and sensations of pleasure and pain
• What condition is linked to depleted levels of dopamine?

  Parkinson’s disease
• What is linked to an excess of dopamine receptors?

  Schizophrenia
• What is norepinephrine important for?

  Attentiveness, emotions, sleeping, dreaming, and learning
• What role does norepinephrine play when released as a hormone into the blood?

  Causes blood vessels to contract and heart rate to increase
• What mood disorder is norepinephrine associated with?

  Manic depression