Oxytocin is a hormone that is known to regulate empathy and social bonding in mammals, such as humans, dogs, and mice. Oxytocin is produced by special cells in the brain and released into the bloodstream or directly into other brain regions. Oxytocin can affect how we behave and feel in different situations, such as hugging, kissing, or helping. According to a study by Akinrinade et al., 2023, oxytocin is both necessary and sufficient for observer zebrafish to imitate the distressed behavior of conspecific demonstrators. This means that without oxytocin or its receptor, observer zebrafish did not show emotional contagion.