Postsynaptic Integration
POSTSYNAPTIC INTEGRATION
Excitatory postsynaptic potentials (EPSPs)
- Depolarize the membrane.
- Makes the membrane less negative.
- Positive ions (ex. sodium) travel into the cell.
Inhibitory postsynaptic potentials (IPSPs)
- Hyperpolarize the membrane.
- Make the membrane more negative.
- Negative ions (ex. chloride) travel into the cell.
- Positive ions (ex. potassium) travel out of the cell.
SUMMATION
Definition
- Adding together of EPSPs or IPSPs to influence the activity of the postsynaptic neuron
Temporal summation
- Presynaptic neuron signals rapidly in succession.
- "successive summation"
Spatial summation
- Multiple presynaptic neurons stimulate the postsynaptic neuron simultaneously.
- "simultaneous summation"