Question

Which of the following is an example of temporal summation?

a. simultaneous activation of an EPSP and an IPSP that therefore offset each other

b. EPSPs produced in rapid succession at one synapse on a dendrite

c. simultaneous activation of EPSPs at two or more synapses on a dendrite

Answer 1

Ans. b

Summation

It is the process by which neurons communicate with each other. There are two types of summation Spatial summation and Temporal summation. Temporal summation occurs only when the target neuron receives a repeatedly short interval input from a lone axon terminal. If the target neuron receives more inputs from different sources then the summation is called spatial summation

The neurons produce only limited responses, that is exciting or inhibiting. Excitation caused by Excitatory neurotransmitters and inhibition caused by Inhibitory neurotransmitters. The neurotransmitters are produced by the presynaptic neuron that cause desirable responses in the post synaptic neuron

EPSP- Excitatory post synaptic potential

EPSP is an electric charge occurs on the post synaptic membrane as a result of excitatory neurotransmitters. EPSP triggers the post synaptic membrane to an excitable state (cause depolarisation of post synaptic cell)

IPSP- inhibitory post synaptic potential

IPSP is an electric charge occurs on the post synaptic membrane as a result of inhibitory neurotransmitters. IPSP cause the post synaptic membrane less excitable  (cause hyperpolarisation of post synaptic cell)

For a temporal summation, the second EPSP should strike membrane of the neuron during the first.