Choichiro Asano

Circadian pattern of stress response to affective cues of foot shock

Abstract Formation of gastric lesions, changes in body weight and changes in serum level of endogenous chemical substances in response to stressful stimuli were studied. To examine the influences of stressful events on bodily responses, the stimuli were introduced in the terms of affective communication by using a communication box. The “Sender” received physical stimuli of electric foot shocks and the “Responder” received affective information such as visual, auditory, and olfactory cues from “Sender” with no exposure to foot shock. The “Responder” exhibited significantly more severe gastric lesions than the “Sender.” The degree of susceptibility to the formation of gastric lesions and weight reduction increased when the stimuli were administered during the dark cycle. Changes in the level of endogenous chemical substances were not significant. The results indicated that a circadian rhythm can be detected in susceptibility to gastric lesions in response to indirect stimulus cues.