If five action potentials arrive at the same synapse in very close succession, which of the following would occur?

A) The direction of the action potential is reversed.
B) Temporal summation occurs.
C) Spatial summation occurs.
D) Hyperpolarization occurs.
E) Depolarization always occurs.

Temporal summation occurs when multiple action potentials arrive at a synapse in quick succession, effectively summing their effects to possibly trigger a new action potential in the postsynaptic neuron. Spatial summation, on the other hand, involves simultaneous inputs from multiple locations. The direction of the action potential is not reversed, and whether hyperpolarization or depolarization occurs depends on the type of neurotransmitters released, not the frequency of action potentials.