Explain how a primary sensory neuron transmits information about the intensity of a stimulus to a secondary sensory neuron at a chemical synapse (i. e. explain temporal summation of postsynaptic potentials).

Answer:Information, in the form of nerve impulses, reaches the spinal cord through sensory neurons of the PNS. These impulses are transmitted to the brain through the interneurons of the spinal cord ... The spinal cord is thus responsible for mediating all information flow between the body and the brain.