The development of cardiorespirography with data processing enables to perform polygraphic recordings. However the standardized results supplied by this new generation of equipment cannot be used directly and need to be validated and analized by the clinician. The confrontation of the cardiac and respiratory curves allows a semiological analysis of the cardiac and respiratory functions and of their relationships in the various syndromic contexts encountered in the neonate (bradycardia and other cardiac arythmia, central or obstructive apnea, thoracic hypoampliation, periodic breathing).