A neurostimulation system, comprising: an implantable medical device, IMD, comprising a neurostimulator coupled to an electrode assembly, said neurostimulator adapted to deliver a stimulation signal to a patient, said stimulation signal comprising an ON time and an OFF time; and a control system programmed to: deliver a plurality of stimulation signals at a first frequency, each stimulation signal having at least one parameter setting different than the parameter settings of the other stimulation signals in the plurality of stimulation signals for a range of parameter settings; monitor a heart rate of a patient implanted with the IMD during delivery to the patient of the plurality of stimulation signals at the first frequency across the range of parameter settings, wherein monitoring the heart rate comprises monitoring a baseline heart rate during the OFF time periods of the stimulation signal and monitoring a heart rate response during the ON time periods of the stimulation signal; identify a first subset of the plurality of stimulation signals with parameter settings within the range of parameter settings during which tachycardia is detected during the ON time periods of the stimulation signal, the tachycardia defined by a heart rate increase; identify a second subset of the plurality of stimulation signals with parameter settings within the range of parameter settings during which bradycardia is detected during the ON time periods of the stimulation signal, the bradycardia defined by a heart rate decrease greater than a threshold; and identify a neural fulcrum zone corresponding to a third subset of the plurality of stimulation signals with parameter settings within the range of parameter settings during which a transition heart rate response is detected during the ON time periods of the stimulation signal, said transition heart rate response between tachycardia and bradycardia showing no change from the base line heart rate or a decrease from the baseline heart rate of less than 5%. an implantable medical device, IMD, comprising a neurostimulator coupled to an electrode assembly, said neurostimulator adapted to deliver a stimulation signal to a patient, said stimulation signal comprising an ON time and an OFF time; and a control system programmed to: deliver a plurality of stimulation signals at a first frequency, each stimulation signal having at least one parameter setting different than the parameter settings of the other stimulation signals in the plurality of stimulation signals for a range of parameter settings; monitor a heart rate of a patient implanted with the IMD during delivery to the patient of the plurality of stimulation signals at the first frequency across the range of parameter settings, wherein monitoring the heart rate comprises monitoring a baseline heart rate during the OFF time periods of the stimulation signal and monitoring a heart rate response during the ON time periods of the stimulation signal; identify a first subset of the plurality of stimulation signals with parameter settings within the range of parameter settings during which tachycardia is detected during the ON time periods of the stimulation signal, the tachycardia defined by a heart rate increase; identify a second subset of the plurality of stimulation signals with parameter settings within the range of parameter settings during which bradycardia is detected during the ON time periods of the stimulation signal, the bradycardia defined by a heart rate decrease greater than a threshold; and identify a neural fulcrum zone corresponding to a third subset of the plurality of stimulation signals with parameter settings within the range of parameter settings during which a transition heart rate response is detected during the ON time periods of the stimulation signal, said transition heart rate response between tachycardia and bradycardia showing no change from the base line heart rate or a decrease from the baseline heart rate of less than 5%. deliver a plurality of stimulation signals at a first frequency, each stimulation signal having at least one parameter setting different than the parameter settings of the other stimulation signals in the plurality of stimulation signals for a range of parameter settings; monitor a heart rate of a patient implanted with the IMD during delivery to the patient of the plurality of stimulation signals at the first frequency across the range of parameter settings, wherein monitoring the heart rate comprises monitoring a baseline heart rate during the OFF time periods of the stimulation signal and monitoring a heart rate response during the ON time periods of the stimulation signal; identify a first subset of the plurality of stimulation signals with parameter settings within the range of parameter settings during which tachycardia is detected during the ON time periods of the stimulation signal, the tachycardia defined by a heart rate increase; identify a second subset of the plurality of stimulation signals with parameter settings within the range of parameter settings during which bradycardia is detected during the ON time periods of the stimulation signal, the bradycardia defined by a heart rate decrease greater than a threshold; and identify a neural fulcrum zone corresponding to a third subset of the plurality of stimulation signals with parameter settings within the range of parameter settings during which a transition heart rate response is detected during the ON time periods of the stimulation signal, said transition heart rate response between tachycardia and bradycardia showing no change from the base line heart rate or a decrease from the baseline heart rate of less than 5%.