How Do Neurons Become Excited?

Neurons become excited in response to a stimulus. Sensory neurons are sensitive to specific stimuli in their surrounding environment. For example, sensory neurons found in human skin are sensitive to touch, pain, and change in temperature outside of the body. Meanwhile, sensory neurons located inside the body are sensitive to pain and changes in temperature inside the body. Sensory receptors in the ears, eyes, nose, and mouth register sound, light, smell, and taste, respectively. Once these neurons are excited by a stimulus, the excitability or impulse moves along that neuron toward the brain, where it is interpreted. Our brain initiates impulses as well. Some of these impulses travel throughout the brain for thinking processes and memory recall. Or these impulses may travel away from the brain toward destinations outside the central nervous system such as skeletal muscle, the heart, and other organs.