Palagi, E., Leone, A., Mancini, G. and Ferrari, P.F. (2009) Contagious yawning in gelada baboons as a possible expression of empathy. Proceedings of the National Academy of Sciences of the United States of America, 106, 19262-19267. doi:10.1073/pnas.0910891106

has been cited by the following article:

• TITLE: Is yawning a tool for wakefulness or for sleep?

  AUTHORS: Dmitry Arbuck

  KEYWORDS: Yawning; Wakefulness; Chest Breathing; Chest Inhaling

  JOURNAL NAME: Open Journal of Psychiatry, Vol.3 No.1, January 29, 2013

  ABSTRACT: Numerous theories as to why we yawn have been advanced, but yawning appears to be a complex phenomenon that is difficult to study. The physiology of yawning with its sharp chest inhalation, along with its contagious nature, can be explained by an arousal theory, that is, yawning promotes vigilance and alertness within a group that overrides a drive to sleep. Other theories of yawning, such as brain thermoregulation, are not necessarily excluded by the arousal theory but may be the results of yawning rather than its cause.