Thus, barroreceptors act as differential-sensors. The frequency during the rising systolic pressure is distinctly greater than that in the diastole. Arterial baroreceptor nerve fibers are buffer nerves concerned with short-term buffering of the blood pressure. The afferent signals are conducted to the nucleus of the solitary tract in the medulla. This nucleus is the site confluence for both baroreceptor and chemoreceptor signals.
Stimulation here inhibits sympathetic structures and enhances parasympathetic structures.
Thus, a rise in arterial pressure causes vasodilatation and a fall in heart rate, both of which contribute to a lowering of blood pressure. A primary fall in arterial pressure elicits vasoconstriction and a rise in heart rate, both of which contribute to a rising blood pressure. In summary, when the arterial pressure is increased, the sensors are stretched, signals are transmitted into the central nervous system. Feedback signals are sent back to reduce arterial pressure downward toward the normal level. This is a process of negative feedback .