Comparative adaptive functions of vasopressin and oxytocin

Individual and species differences are commonly observed. These differences are adaptive and context-dependent. Early life experiences can epigenetically tune these systems (see text and Fig. 3).

Hypothesized FunctionsVasopressin – or AVPR ActivationOxytocin – or OXTR Activation
Life history strategies and reproductive investmentMore primitive – fasterMore modern – slower
Lower parental investment and more offspringGreater parental investment and fewer offspring
Responses to challenges defense strategiesMobilization (fight-flight)Immobilization without fear
Amplifying stress and fearStress coping and resilience
Reduced cooperationSocial cooperation
Reactive aggressionPositive social behaviors
Immobility with fearImmobilization without fear
Freezing or subordination?Parental and sexual behavior
Mild stressRelease of vasopressinInhibition of oxytocin?
Extreme acute stressRelease of vasopressinRelease of oxytocin
Chronic stressRelease of vasopressin?Inhibition (males?); release of oxytocin (females)
Autonomic nervous systemaSympathoadrenalParasympathetic (vagalb)
InflammationProinflammatory (primarily)Anti-inflammatory
PainIncreasing or reducing?Prevention or reducing
  • a Interactions between AVP and OXT and the autonomic nervous system support flexibility in behavioral, emotional states and allow different strategies for dealing with challenges with effects that may differ between males and females.

  • b The vagus nerve has more than one branch arising from different source nuclei in the brainstem. The more modern branch arises in the ventral-vagal complex and supports social behaviors and features that are unique to mammals, such as facial expression, social engagement, and language. The more primitive branch arises in DMX (i.e., 10th cranial nerve) and is associated with conservation of energy in response to extreme stressors or trauma (Porges, 2011).