The Role of Oxytocin: A Review

The aim of this paper is to provide a critical
review of the role of oxytocin. Oxytocin is a
neuropeptide hormone produced in the
hypothalamus, stored in, and released from, the
posterior pituitary gland (neurohypophysis).
Secretion of oxytocin is a neuro-endocrine
response. The actions of oxytocin are mediated
by specific, high affinity oxytocin receptors.
Oxytocin is a very interesting hormone that has
both peripheral (hormonal) actions, and actions
in the brain and central nervous system. This
presentation will provide a critical review of
evidence to date and highlight relevant areas
emerging that will be of interest to
psychologists. Briefly, its peripheral actions are
as follows. Oxytocin is best known for its role in
female reproduction. It is released in large
amounts during parturition resulting in uterine
contraction. This facilitates the birth process,
control of bleeding and involution of the uterus.
Oxytocin has a key role in the ejection of milk
from the breast during lactation (let down
reflex). Furthermore, oxytocin may be involved
in sexual response in humans. The relationship
between oxytocin and sexual response remains
unclear. Meanwhile, its actions on the central
nervous systems are as follows. Once secreted,
oxytocin cannot re-enter the brain because of
the blood-brain barrier. Instead, the behavioural
effects of oxytocin are thought to reflect release
from centrally projecting oxytocin neurons,
different from those that project to the pituitary
gland, or which are collaterals from them.
Oxytocin has been implicated in non-social
behaviours such as pain perception, anxiety
learning and feeding. More recently there has
been increasing interest in the role oxytocin may
play in other behaviours such as social memory
and attachment, sexual and maternal behaviour,
aggression, human bonding and trust. It has
been suggested that oxytocin expression may be
involved human disorders characterized by
aberrant social interactions, such as autism and
schizophrenia. The trust-inducing property of
oxytocin may emerge as a controversial topic. It
has been suggested that the trust-inducing
properties of oxytocin may help those who
suffer from social anxieties and mood disorders
while there is another school of thought that this
potent hormone has the potential for misuse in
the wrong hands.