Andrew Huberman· PhD
are some neurons nerve cells are what we call motor neurons in the sense that they control the contraction of muscles sometimes for walking other neurons control the movements of your fingers scientists call those digits other ones your toes they also control the beating of your heart although that's a slightly different mechanism and slightly different type of tissue than is involved in generating motor movements of your limbs these are neurons that we call motor neurons because their goal or their purpose I should say they don't really know what their their goal or purpose is but what they do is they make sure that muscles contract so that certain things happen in your body like your heart beats or you move your limbs you lift your eyelids or your eyebrows rather and so on and so forth other types of neurons are what we call Sensory neurons they communicate the same way that motor neurons do that is they fire what we call Action potentials which are just electrical signals they release neurotransmitters like any other neuron but they respond to certain events in the environment or the environment within the body but they are not responsible for generating muscular contractions so we call these Sensory neurons some Sensory neurons sense light touch other Sensory neurons sense firm touch other sensory neurons sense pain other Sensory neurons sense light brushing on the skin in fact you have Sensory neurons believe it or not that respond specifically to the light brushing of a hand across your skin any region of your body and if that particular region of your body happens to have hair on it and you stroke the skin in the direction that the hairs lay down we experience that as pleasurable whereas if you stroke in the direction opposite to the the way the hairs lay down we experience that as not pleasurable so these Sensory neurons respond in some cases for instance within the auditory system they respond to sound waves and your eye they respond to photons of light sometimes photons of light of particular wavelengths that we think of as red green blue and so on Sensory neurons don't move muscles they respond to things in the environment and they exist within us so we have Sensory neurons that sense for instance pressure within our head or pressure within our gut how full or empty our gut is pain within our tissues like our liver or or any kind of other internal organ so we've got motor neurons Sensory neurons and then the last kind of neuron is what we call modulatory neurons