Conditions: Healthy
Keywords: Paternal nurturance Oxytocin Vasopressin fMRI Neurobiology
Allocation: RANDOMIZED | Intervention model: CROSSOVER
Enrollment: 35
Healthy volunteers: yes

Brief summary:
The overall goal of this project is to identify the genetic, hormonal, and neurobiological influences on paternal nurturing behavior and to determine if fathers' neural responses to infants can be modulated by neuropeptides known to play a role in parenting in experimental animal models.

The aim is to determine if pharmacological manipulation of central oxytocin (OT) and vasopressin (AVP) levels influences the neural response to viewing pictures of one's own infant or to hearing cry stimuli. In a double-blind procedure, fathers with 1-3 year old children will be scanned on two separate occasions; once under the influence of OT/AVP and once under the influence of placebo. Fathers will be randomized to either OT or AVP, and order of administration of drug and placebo will counterbalanced across subjects. Fathers will be scanned while viewing pictures of their own and an unknown child and while listening to unknown infant cry stimuli.

The investigators hypothesize:

* OT will augment the ventral tegmental area (VTA), ventral striatum and medial orbitofrontal cortex (mOFC) response to viewing pictures of one's own child, and will augment the primary auditory cortex (AI) response of fathers to infant cries.
* AVP will augment the lateral septum response to viewing own child pictures.

Detailed description:
30 fathers of children aged 1-3 will participate in two functional imaging sequence (fMRI) sessions, once under the influence of OT/AVP, and once under the influence of placebo. Fathers will be restricted to men who are living with their biological child and an adult partner (male or female) that they are in a committed relationship with. All fathers will receive two fMRI scans on two different occasions, separated by 2-10 days. 15 fathers will be randomized to intranasal OT, the other 15 will be randomized to intranasal AVP. Within each drug group, the order of administration of drug and placebo will counterbalanced across subjects, such that 15 will receive OT/AVP first, and 15 will receive OT/AVP second. During the fMRI scans, fathers will view pictures of their own and unknown children, as well as unknown adults. Afterwards, while still in the scanner, they will listen to infant cry and control stimuli. After exiting the scanner, fathers will again listen to the cry stimuli and will rate their emotional reaction to the cry stimuli on the following dimensions using a 7 point likert scale: irritated, sympathetic, alarmed, angry, upset, compassionate, distressed, annoyed, and tender.

Arms:
arm 1: The OT + placebo group will self-administer no more than 1 ml solution of oxytocin or placebo in each nostril; five (5) sprays per each nostril, for a total of ten (10) sprays. The order of administration of drug and placebo will counterbalanced across subjects, such that half will receive OT first, and half will receive OT second. arm 2: The AVP + placebo group will self-administer no more than 1 ml solution of vasopressin or placebo in each nostril; five (5) sprays per each nostril, for a total of ten (10) sprays. The order of administration of drug and placebo will counterbalanced across subjects, such that half will receive AVP first, and half will receive AVP second.

Interventions: intervention 1: Oxytocin intervention 2: Vasopressin intervention 3: Placebo
Intervention descriptions: intervention 1: 1 ml solution in each nostril; five (5) sprays per each nostril, for a total of ten (10) sprays intervention 2: 1 ml solution in each nostril; five (5) sprays per each nostril, for a total of ten (10) sprays intervention 3: 1 ml solution in each nostril; five (5) sprays per each nostril, for a total of ten (10) sprays

Protocol document: