Question

Explain how EPSPs are used to make the postsynaptic neuron fire. Distinguish between temporal and spatial summation. How do IPSPs factor into this?

Answer 1

If EPSPs is depolarising the inside of the cell is more positive which brings the membrane potential closer to its threshold for firing an action potential for the postsynaptic neurons below threshold for firing an action potential.

Temporal occurs when a single single presynaptic neurons fires many time in a succession causing the postsynaptic neurons to reach its threshold as fire where as spatial summation occurs when excitatory from many different presynaptic causes the post synaptic neurons to reach its threshold and fire, the main difference between the temporal and spatial summation is that the temporal summation occurs when one presynaptic neuron releases transmitters over a period of time to fire an action potential where as spatial summation occurs when multiple presynaptic neurons releases together to fire an action.

An inhibitory postsynaptic potential (IPSPs) is a temporary hyper polarisation of postsynaptic membrane caused by the flow of negativity charged ions into the postsynaptic cell.

An IPSP is received when an inhibitory presynaptic cell connect to the dendrite fires an action potential.