skin when it was repeated several times. Columbia University’s Nobelist in the brain sciences, Eric Kandel studied the neural mechanisms of habituation as a primitive, accessible and fundamental example of learning, the association of a nonresponse to a usually evocative stimulus, in Aplysia californica. The sea snails learned not to respond to a local irritation with a gill-withdrawal response when exposed to it many times. They learned to stop paying attention to the perturbation. The background noise appears to disappear after a little time in the Mall. Though his exploration of its synaptic mechanisms involved the neural circuit of the gill-withdrawal reflex in the marine snail, its generality and human relevance is well established. Hundreds of papers can be found reporting the results of studies of habituation in normal humans under all kinds of circumstances as well as in psychopathological conditions. That it samples something both fundamental and persistent is suggested by studies in children by one of Kandel’s students, Michael Lewis. He found that the rate of habituation of a startle response to a bright light in one-year-old human infants predicted success in many kinds of learning and other cognitive functions when the children were tested again at the age of four. Pavlov’s experiments studied habituation of the classically conditioned salivary response to meat powder- coupled bell sounds in dogs in which the bell was followed by nothing, not only led to inhibition of the salivary response with unreinforced trial repetition but generalization of the inhibitory state such that dogs were observed to freeze in motionless catatonic states for hours. In the language of our statistical measures, the fixation of the dog’s behavior would manifest minimal entropy in the form of H7 = Hu = 0 and the lowest complexity values for AC and srs. Entheogenic agents like LSD or mescaline inhibit the process of habituation and fixation, maximizing the entropy of behavioral