The computer produces in Stan the physiological response that the drug would have produced in a patient with that medical condition.

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An additional test was set up to measure the physiological response of volunteers.

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At first she attributed this to the range of high harmonics used by Mozart, but her later research, which manipulated the frequency levels of various compositions, showed that frequencies alone were not responsible for this physiological response.

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Tipton, who conducts research on the human body's physiological and psychological response to adverse environments, found that it takes as few as five immersions in icy water for the body to develop a tolerance that can reduce the risk of cold-shock response by half.

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Nor does empathy suggest a physiological "reason" for yawning (after all, we yawn when alone), though Dr. Provine thinks that it may be "a response to and facilitator of change in behavioral or physiological state, " maybe synchronizing a group of people about to embark on a behavioral transition.

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Of great interest is the physiological pathway called the hypoxia-inducible factor, or HIF, which seems to trigger the body's response to low-oxygen levels in tissue.

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