Oxytocin is often called the "love hormone," but a new study says that in people with anxious attachment it may make childhood memories more negative. The work was published in the journal Emotion.
Attachment is a style of forming close relationships that is laid down in childhood. Psychologists call it an internal working model: a set of beliefs about whether other people will be available and responsive. Anxiously attached people crave closeness but fear being abandoned and react especially sharply to threats in relationships. Avoidant people, by contrast, keep their distance so as not to be disappointed.
Oxytocin is a hormone and chemical messenger involved in childbirth, feeding and the formation of pair bonds. In experiments on mice and sheep it was necessary for recognizing offspring and conspecifics. Early experiments on humans gave it a reputation as a universal enhancer of trust and empathy. However, newer data support the social salience hypothesis: oxytocin works as an amplifier of emotions, highlighting social information regardless of its sign.
A team led by Melissa Chemirani and Jennifer Bartz of McGill University (Canada) conducted an experiment with 77 men and women. Each participant came twice: on one day they received oxytocin as a nasal spray, on the other a placebo (dummy). Neither the subjects nor the experimenters knew what exactly was administered on a given day. Such a design makes it possible to compare the reactions of the same person under two conditions.
After the drug began to act, participants were offered words related to attachment, for example "protect" or "get upset." Using these cues they had to recall specific childhood episodes connected with their mother. The researchers then selected one positive and one negative memory and asked them to talk about them aloud. Independent raters read the transcripts and assessed the emotional tone. In people with high attachment anxiety, oxytocin intensified negative and weakened positive descriptions of the mother compared with placebo.
In addition, the texts were analyzed by two computer programs that determine emotional tone. They partially agreed with the humans: anxiety influenced negative vocabulary. But in the software analysis the significant effect appeared in participants with low anxiety - in them oxytocin reduced the negative tone of memories. The programs found no differences in positive vocabulary.
In people with an avoidant style, oxytocin did not change the emotional content of memories about the mother. However, after the task they filled out a questionnaire about how willing they are to share personal things. Avoidant people were already less candid, and under the influence of oxytocin they became even more closed.
The authors caution: the results concern only memories about mothers, the sample was young and predominantly white and Asian, and the discrepancies between humans and programs point to the limitations of automatic text analysis. In addition, oxytocin is not a universal remedy for relationship problems: by intensifying existing fears, without the accompaniment of a specialist it can cause harm.