Scientists knew that oxytocin had
a role to play in strengthening the bond between mother and child. But
now they have found out that oxytocin also affects neural signals in the
brain of the mother and influences her social responses.
In an experiment conducted on laboratory mice with pups, scientists
discovered that when the little ones were separated from their mums,
they produced ultrasonic SOS calls. The mother mouse picked up these
signals to locate her pups. The mother mice responded similarly —
started looking for their pups — when the scientists played the pup
distress calls on speakers.
The scientists investigated how oxytocin is involved in this behavior.
The left auditory cortex
of the brain receives the sound signals. This part of the brain has a
large number of oxytocin receptors. The hormone levels increased in the
mother mice when they heard the distress calls of their pups. Oxytocin
not only made the mother mice respond to their pups but also inhibited
her brain’s ability to process other social signals.
In the above experiment, it was also found that female mice without pups did not respond to distress calls
made by pups of other mice. But when they were injected with oxytocin,
they responded to the distress calls by rushing to search for and rescue
the pups even though those were not their own.
This newly-discovered role of oxytocin is, however, not surprising.
After all, babies are helpless and unable to defend themselves if they
are separated from their mums. So it seems natural that nature intended
oxytocin to exert influence on mothers in this way.
Oxytocin and Our Responses to Social Stimuli
The oxytocin system is critical to the expression of three basic social bonds
— parental, filial, and romantic. According to one study, the levels of
oxytocin remain more or less stable in individuals over extended
periods of time and go on to play crucial role in the expression of
other types of social attachment behavior later in their lives.
Scientists also believe that oxytocin interacts with neural,
physical, and mental factors to develop unique expressions of social
cognition and empathy in
humans. For instance, scientists have discovered that the quality of
early-life parental care tends to influence the way children form
attachments in adulthood.
In 2005, an interesting study was conducted on two groups of
children. The kids in one group were raised by their biological parents.
The children in the other group were adopted, but they had been raised
in orphanages where they were deprived of the typical care-giving
environment that the children of the other group were raised in. The
oxyotcin levels in the children from both groups were monitored when
they were in contact with their mothers—biological or adopted. It was
found that the children who were raised by their biological parents
showed an increase in oxytocin levels while levels in the other group of
children remained constant. So it is evident that early-life social
experience influences the way individuals form relationships later on in
their lives.
The above findings led scientists to explore the connection between
oxytocin and social disorders that develop during childhood, like autism spectrum disorders.
And, to their surprise, they also found out that oxytocin plays a role
in managing the symptoms of certain mental illnesses like schizophrenia.
Oxytocin and Mental Illnesses
The “love hormone” oxytocin floods us with feel-good vibes. It has another beneficial face too.
According to a recent study, intranasal administration of oxytocin
can improve the ability of schizophrenia patients to recognize negative
emotions, like fear, in other people. It was found during the study that
schizophrenia patients whose baseline performance was below median
level showed greater improvement when they were administered oxytocin
compared to patients who were more capable.
These findings have already unleashed a slew of research into the
various aspects that need to be considered before administering oxytocin
for therapeutic purposes to patients suffering from mental illnesses.
For instance, one study suggests that the efficacy of intranasal
administration of oxytocin is dependent on gender, hormonal and genetic
profiles, and attachment history. Other scientists have investigated the
effects of different doses of oxytocin on patients.
These studies are crucial for finding out how long the effects of
oxytocin stays in laboratory patients because elevated levels of
oxytocin can also trigger anxiety.
The Adverse Effects of Oxytocin
The “love hormone” oxytocin has been found to have a disturbing
effect as well when present in more-than-normal amounts in the human
body. For instance, it was shown that oxytocin also influences the
memory. In an experiment conducted on laboratory mice, it was found that
under conditions of social stress oxytocin fires the lateral septum
region of the mouse brain, a region that intensifies memories. This
means that oxytocin turns a stressful experience into a long-standing
painful memory that can trigger anxiety and fear every time an
individual confronts similar stressors in future. Chronic anxiety and fear can also lead to depression.
In another study, it was found that women who reported
less-than-satisfactory quality of relationships with their partners and
longer periods of time in their lives spent without romantic attachments
had more oxytocin and the stress hormone cortisol than women who enjoyed more satisfying relationships.
These findings seem crucial considering that scientists are also
toying with the idea of using oxytocin to manage the anxiety symptoms.
It is evident that oxytocin is not only associated with good and happy
feelings.
The discovery of new faces of oxytocin presents intriguing avenues
for further study. These studies should help scientists and
psychiatrists better understand and accurately analyze why we behave the
way we do in specific social situations and with other human beings.
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