Infants starting from
a position of distress with a corresponding higher
heart rate and agitated behavior have a greater
range of improvement available, which was illustrated
in these studies. However in this study all of
the infants were physiologically stable and asleep
(one hour postfeed), and therefore there was less
scope for change. The current results concur with
other investigations that report that premature infants
have been shown to have lower autonomic
responsiveness to external stimuli in certain sleep
states