Synaptic Transmission

• What is the biological structure discussed in this material?

  Synapse
• Why is the synapse important in biological psychology?

  It helps understand information transmission and drug effects
• What is synaptic transmission?

  • Process of information passing between neurons
  • Involves electrical impulses and neurotransmitters
  • Critical for brain function and psychoactive drug effects
• What is the gap between two neurons called?

  Synaptic cleft
• How do electrical impulses travel through neurons?

  As action potentials
• What must happen for information to cross the synaptic cleft?

  It must be transmitted as chemical messages
• What are the chemicals called that transmit information across the synapse?

  Neurotransmitters
• What happens when an action potential reaches the axon terminal?

  Vesicles merge and release neurotransmitters
• How thick is the synaptic cleft?

  20 to 40 nanometers
• What do the receptors on the postsynaptic neuron do?

  Detect the presence of neurotransmitters
• What is the role of transport proteins in the presynaptic neuron?

  They take neurotransmitters back into the cell
• What is the process of summation in synaptic transmission?

  • Effects of excitatory and inhibitory neurotransmitters
  • Added and subtracted to determine overall effect
  • Determines if a new action potential forms
• What happens during depolarization in the postsynaptic cell?

  Positively charged sodium ions enter the cell
• What effect do excitatory neurotransmitters have on the postsynaptic neuron?

  They make the electrical charge more positive
• What do inhibitory neurotransmitters do to the postsynaptic neuron?

  They hyperpolarize the neuron, making it more negative
• What is the typical firing rate of a neuron?

  5 to 50 times a second
• What do SSRIs do in the brain?

  They block serotonin reabsorption, increasing levels
• How does cocaine affect neurotransmitter transmission?

  It blocks dopamine reabsorption, increasing its signal
• What is the significance of synapses in brain function?

  • Fundamental for consciousness and memory
  • Enable complex interactions between neurons
  • Essential for all brain activities
• How many neurons are estimated to be in the human brain?

  About 100 billion neurons
• How many synaptic connections can a single neuron have?

  Up to 15,000 synaptic connections
• How many synapses does an average 20-year-old male have?

  About 170 trillion synapses
• How long would it take to count 100 synapses per second?

  Just under 5,500 years
• What is the comparison made between synapses and stars in the Milky Way?

  • Estimated 250 billion stars in the Milky Way
  • Equivalent to around 680 Milky Way galaxies worth of synapses
• What is the main takeaway about the brain's complexity?

  It is a powerful machine due to synapse interactions