Effects of Proximate Cues of Diving Response on Human Heart Rate
Linda Bo Lim Lee
Tuesday AM Lab
ABSTRACT
The objective of this experiment was first, to demonstrate the existence of bradycardia reflex as a result of diving response in humans and second, to examine whether specific stimuli or proximate cues trigger this slowing of the heart rates. In order to simulate the dive, subjects’ faces were submerged into basins with 15°C water. The pulses of the students who were under various conditions such as apnea or cold water were obtained during their dives. The data were paired for each subject under different experimental conditions and statistical significance was examined. While the result from experiment revealed that both the contact with water and the coldness of water decreased the heart rate during a dive, due to lack of accuracy in one of the experiments, apnea was not found to be one of the cues of…show more content… The room temperature apnea, on the other hand, failed to support the effect of non-breathing on diving response. But due to the lack of precision of the data, the relationship between apnea and bradycardia cannot be simply determined without further examination. This experiment ultimately discovered that in addition to the deprivation of oxygen, which limits the oxygen supply to only the essential parts of the body, that the contact with cold water is also responsible for initiating the diving response (Hibert and Burch, 2003). The slowing down of the heart rate may, in fact, be attributed to the activation of the nerve system especially around the face due to sensation of cold water against the skin (Reyners et al. 2000). Therefore, the wetness and the coldness of the water were identified as the proximate cues of bradycardia