We have all laughed at videos of little ducklings following inappropriate things around. Ducks and geese both imprint on the first moving object, that is larger than they are, that they see upon hatching. Imprinting is designed to ensure survival since the hatchling must rely on its mother for both food and protection.
Oxytocin is responsible for this behaviour. It might be alarming for you to know that oxytocin plays a similar role in bonding in humans. While siginificantly fewer people follow someone around all of the time, bonding is just as important in human social interactions and survival of the species as it is to the duckling.
Oxytocin, which is released in response to many social activities, is one of a cocktail of chemicals that are released when people interact with one another. Opioids, norepinephrine, vasopression and likely more, all seem to play a role.
Opioids that are released during relationships may be responsible for how awful we feel during a break up. We become addicted to them, in the same way that we become addicted to taking drugs, and consequently feel the same withdrawal and the associated pain when the relationship ends.
Oxytocin, on the other hand, is instrumental in the formation of social attachments and the reduction of fear, especially fear resulting from social interactions. Simply being with other people can create a certain amount of bonding, even if it is just a gathering. This mild effect may be totally offset by how much you dislike the people, however.
The more intimate the interaction, the more oxytocin is produced and it is produced in large quantities during childbirth, breastfeeding and coitus. It is not difficult to see how bonding can be very valuable during these activities ensuring a pair is created. This is in the best interest of the survival of our species since babies with loving parents are the most likely to thrive.
There are however, people that are not as affected by oxytocin and their personalities are associated with callous-unemotional traits. So, in a relationship with say, a narcissist, you get a hit of oxytocin and further bond and they do not have the same hormonal response. This immediately tips the power into their favour. They are not as bonded as you are.
Ironically, even in a bad relationship, the oxytocin that is produced, makes you feel “safer” even if you are not actually safer. In addition to that, oxytocin is responsible for the feeling that “our group is better than their group” and supports the practise of excluding others. This double wammy makes it very difficult for a person to be rational when they have pair bonded with an unfavourable person. Simply put, they feel safer with this person and they feel separate from other groups of people.
Threatening situations, even those created by your partner, may encourage the return to a secure base and the strengthening of social bonds, which are, provided by your partner. So, a vicious cycle ensues. You feel threatened and then you form a tighter bond with the person threatening you. We have all seen someone that chooses to stay with someone that is not good to them. It is nice to know that it is not just a lack of judgement.
There are two take away messages here. First, you should make sure that you really like someone before you become intimate with them because the hormones that you produce during intimate contact can make sober thought difficult. The second is that if we find ourselves in these terrible relationships, perhaps with a narcissist for instance, we should be gentle with ourselves. Our biology, in these cases, is working against our greater good, not unlike the duckling imprinting on a predator.