The effect of tactile stimulation on heart rate (HR) in humans was investigated under three conditions: 1) Experimenter outside of room in which subject is sitting; 2) experimenter in the room with the subject; 3) experimenter in the room while touching the subject's right wrist. Nonsignificant increases in HR were observed when the experimenter entered the room (X = 0.64 beats per minute (bpm)). Conversely, large decreases occurred when the experimenter placed his hand on the subject's wrist (X = 9.16 bpm, p is less than 0.05). To determine if tactile stimulation alone accounts for these differences three comparisons were made in a second experiment: 1) Experimenter out of test room, subject touches own wrist; 2) experimenter in room standing near subject; 3) experimenter touching subject's wrist. Subjects showed slightly elevated HR during the self-touch condition (X = 1.26 bpm, not significant). Although no change was noted with the experimenter standing beside the subject, there were decreases, as in Experiment I, when the experimenter touched the subject's wrist (X = 1.75 bpm, p is less than 0.05). These results suggest that the observed decreases in HR were contingent upon another person's touch. While self-tactile stimulation produced a slight increase in HR, tactile stimulation by another caused bradycardia.
Psychological literature often conveys the impression that of the two divisions of the autonomic nervous system, the sympathetic system plays the only important role in the mobilization of bodily resources to meet a stress or emergency situation. This stems from Cannon's classical work (Bazett, 1956), which vividly portrays the difficulty a sympathectomized animal has in adjusting to disturbing stimuli and which simultaneously emphasizes the restorative and protective functions of the parasympathetic system. That the parasympathetic system plays a very important role in cardiac acceleration in dogs was first shown by Gasser and Meek (1914), who found that inhibition of the vagus nerves accounts for most of the heart rate (HR) acceleration occurring in exercise. The question arises of whether the vagus nerves play a similar role in the cardiac component of the orienting reflex (OR) and the CR. The present paper provides information concerning this question; we report the effects of atropine sulphate on the auditory OR and the defense CR.
METHOD
SubjectsSix mongrel dogs, one to t\vo 3'ears old, four males and two females, were trained to stand quietly in a conditioning stand. The stand was located in a soundshielded room isolating the 5s from the experimenters, recording equipment, and adventitious stimuli.
ProcedureOR training. Five of the six 5s were given several daily sessions consisting usually of 10 to 15 repetitions
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.