  The cries of several full term newborns, recorded during blood sampling, were
analyzed. Spectrograms showed the appearance of irregular patterns related to
the pain assessed using the method of the DAN scale. In particular, the
appearance of Noise concentration Patterns (NP) in spectrograms was related to
the increase of the pain suffered by the newborns. In this scenario, pain
constitutes a bifurcation parameter for the vocal folds dynamic, inducing a
Ruelle-Takens-Newhouse chaotic transition.
