A system for the non-invasive detection and distinction between obstructive and central apneas, comprising: a device that monitors circulatory pulse waveforms recorded from the person's body and monitors circulatory pulse systolic upstroke waveforms recorded from the person's body; wherein the device is configured to: normalize said circulatory pulse systolic upstroke waveforms such that a magnitude of a trough to peak amplitude of each such systolic upstroke is set to a predetermined value; determine at least one index of the upstroke to characterize the strength of the contraction of the heart during the systolic upstroke phase of a heart beat; determine the variability of said at least one index of the upstroke during a series of heart beats related to the influence exerted upon the heart's pumping action caused by intra thoracic pressure changes brought about by the patient's breathing cycle, or absence of an anticipated breathing cycle, of the person irrespective of vascular tone, determine the detection of and distinction between obstructive and central apneas based upon the at least one index of the upstroke that has been detected, wherein said detection and distinction are based on a high level of variability in the time series of upstroke index during sleep being indicative of the presence of obstructive sleep apnea, and a below-normal-breathing level or no changes in variability in the time series of upstroke index in the upstroke index during sleep being indicative of the presence of central sleep apnea. a device that monitors circulatory pulse waveforms recorded from the person's body and monitors circulatory pulse systolic upstroke waveforms recorded from the person's body; wherein the device is configured to: normalize said circulatory pulse systolic upstroke waveforms such that a magnitude of a trough to peak amplitude of each such systolic upstroke is set to a predetermined value; determine at least one index of the upstroke to characterize the strength of the contraction of the heart during the systolic upstroke phase of a heart beat; determine the variability of said at least one index of the upstroke during a series of heart beats related to the influence exerted upon the heart's pumping action caused by intra thoracic pressure changes brought about by the patient's breathing cycle, or absence of an anticipated breathing cycle, of the person irrespective of vascular tone, determine the detection of and distinction between obstructive and central apneas based upon the at least one index of the upstroke that has been detected, wherein said detection and distinction are based on a high level of variability in the time series of upstroke index during sleep being indicative of the presence of obstructive sleep apnea, and a below-normal-breathing level or no changes in variability in the time series of upstroke index in the upstroke index during sleep being indicative of the presence of central sleep apnea. normalize said circulatory pulse systolic upstroke waveforms such that a magnitude of a trough to peak amplitude of each such systolic upstroke is set to a predetermined value; determine at least one index of the upstroke to characterize the strength of the contraction of the heart during the systolic upstroke phase of a heart beat; determine the variability of said at least one index of the upstroke during a series of heart beats related to the influence exerted upon the heart's pumping action caused by intra thoracic pressure changes brought about by the patient's breathing cycle, or absence of an anticipated breathing cycle, of the person irrespective of vascular tone, determine the detection of and distinction between obstructive and central apneas based upon the at least one index of the upstroke that has been detected, wherein said detection and distinction are based on a high level of variability in the time series of upstroke index during sleep being indicative of the presence of obstructive sleep apnea, and a below-normal-breathing level or no changes in variability in the time series of upstroke index in the upstroke index during sleep being indicative of the presence of central sleep apnea.