Patients with low oxytocin might also have low empathy as a result of their medical condition.
Oxytocin is a hormone produced in the hypothalamus, which is a very small part of the brain that controls many of our bodily functions, including our appetite, thirst, sleep, mood, and libido.
The hormone is secreted and stored by the pituitary gland, a pea-sized organ at the base of our brain that regulates many vital bodily functions, such as metabolism, physical growth, sexual maturation, and reproduction.
Oxytocin has earned the nickname "the love hormone" because we secrete it when we form bonds with our romantic partner, our children, and even our pets.
It is released during sex and childbirth to aid and facilitate reproduction. It is also secreted when we stare into the eyes of our loved ones, or when we hug them.
The "love hormone" has been shown to regulate social behavior, as it increases feelings of trust and prompts pro-social and moral behavior. Oxytocin reduces aggression and stress levels.
New research strengthens the link between empathy and oxytocin, by examining how patients with low oxytocin levels respond to empathy tasks.
Oxytocin increases empathy
Oxytocin levels have been previously linked to empathy. Some studies have suggested that increasing oxytocin improves cognitive empathy and helps with social adaptation in patients with autism spectrum disorder (ASD).
A study of 13 participants with autism found that after inhaling oxytocin, patients displayed stronger interactions with the most socially cooperative peers and reported greater feelings of trust.
Other studies have shown that oxytocin also increases emotional empathy and enhances socially reinforced learning in healthy men.
In fact, oxytocin might selectively help us remember things we learned in a positive social environment, and forget what we learned in a highly stressful learning context.
Reduced empathy in neurology patients with low oxytocin
Researchers from the University of Cardiff in the United Kingdom looked at patients with medical conditions that might have impaired their oxytocin production.
The conditions researched were cranial diabetes insipidus (CDI) and hypopituitarism (HP). In CDI, the body produces reduced levels of arginine vasopressin, which is a hormone similar to oxytocin and also produced in the hypothalamus.
In HP, the pituitary gland does not produce enough hormones.
The researchers' hypothesis was twofold: first, oxytocin levels were expected to be lower in patients with CDI and HP. Second, it was predicted that lower levels of oxytocin would decrease empathy in these patients.
Led by Katie Daughters, from the Neuroscience and Mental Health Research Institute at the University of Cardiff, the research team examined a total of 55 individuals, of whom 20 had CDI, 20 had HP, and 15 were healthy controls.
Daughters and colleagues took saliva samples from the participants both before and after the empathy tests, which consisted of the "Reading the Mind in the Eyes" task and the "Facial Expression Recognition" task.
These tests revealed lower levels of oxytocin in both CDI and HP patients, but not low enough to be statistically relevant.
However, both CDI and HP patients performed significantly worse in empathy tests than their healthy counterparts.
CDI and HP patients performed much worse in both identifying high-intensity facial expressions and "reading someone's mind" in their gaze. The participants' ability to recognize facial expressions was accurately predicted by their oxytocin levels.
Patients with the lowest oxytocin levels also performed the poorest in the facial expression recognition task.
The study was presented as a conference abstract by Daughters and team at the Society for Endocrinology annual conference in the U.K.
Further studies needed to confirm findings
As Daughters points out, "this is the first study which looks at low oxytocin as a result of medical, as opposed to psychological, disorders."
"If replicated," Daughters continues, "the results from our patient groups suggest it is also important to consider medical conditions carrying a risk of low oxytocin levels."
Daughters suggests introducing testing practices that would check for oxytocin levels in certain patients.
"Patients who have undergone pituitary surgery, and in particular those who have acquired CDI as a consequence, may present with lower oxytocin levels. This could impact on their emotional behavior, and in turn, affect their psychological well-being. Perhaps we should be considering the introduction of oxytocin level checks in these cases."
The authors hope their research will encourage new, similar studies that will reinforce their findings.