Neurobiological Bases of Paternal Nurturance

James K. Rilling, PhD35 enrolled

Overview

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.

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.

Study Type

INTERVENTIONAL

Allocation

Eligibility

Sex: ALLMin age: 18 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * above 18 * biological fathers of 1-3 year old infants who are currently cohabitating with the child's mother * normal or corrected-to-normal vision of 20/40 Exclusion Criteria: * current or past history of mental illness * active medical or neurological disorder * current or past history of alcohol or drug dependence * claustrophobic (at the discretion of the PI with subject consultation) * history of seizures or other neurological disorder * history of hypertension, cardiovascular disease, nephritis, diabetes or other endocrine diseases or malignancy * ferrous metal in any part of the body * history of asthma or migraine headaches (can be included at the discretion of the study physician or nurse practitioner if episodes are infrequent and no active problems at time of study, not medicated) * history of head trauma or psychiatric illness, as well as those who are receiving or have received over the past year, medication with known psychoactive effects (included at the discretion of the PI as these are exclusion criteria due to data quality concerns and not safety concerns; head trauma should be minimal enough deemed by the PI)

Outcomes

Primary Outcomes

Mean Percent Signal Change in Ventral Tegmental Area (VTA)

The effect of the drug will be assessed by determining changes in brain activation to own child pictures versus adult pictures (O-A) between OT treatment and placebo treatments (OT-PL) from functional magnetic resonance imaging (fMRI). Changes will be assessed in the OT group only per protocol.