The contagious aspect of yawning is a well-known phenomenon that exhibits variation in the human population. Despite the observed variation, few studies have addressed its intra-individual reliability or the factors modulating differences in the susceptibility of healthy volunteers. Due to its obvious biological basis and impairment in diseases like autism and schizophrenia, a better understand...

Contagious yawning has been reported for humans, dogs and several non-human primate species, and associated with empathy in humans and other primates. Still, the function, development and underlying mechanisms of contagious yawning remain unclear. Humans and dogs show a developmental increase in susceptibility to yawn contagion, with children showing an increase around the age of four, when als...

This paper discusses contagious effects of expectation in financial markets. We first review developments of Japanese financial markets towards the end of 1997 when a number of financial institutions collapsed. We then consider a simple model and study conditions under which contagious expectation triggers a financial crisis. Finally, based upon these, we derive some policy implications regardi...