Effects of PURPLE Cry Intervention

Biological Bases of Individual Variation in Paternal Nurturance

The proposed study is designed to investigate whether the PURPLE Crying program attains efficacy by optimizing the neural response in the anterior insula, and augmenting activity in regions of the brain known to be important for emotion regulation.

The aim is to determine the effects of the PURPLE Cry Intervention by investigating the following:

• independent variables that may affect a father's neural response to infant cries
• effects of the PURPLE cry intervention, compared to a control intervention, on fathers' reported aversiveness and empathy in response to cry stimuli
• effects of the PURPLE cry intervention, compared to a control intervention, on fathers' neural response to unknown infant cries compared to a tone control
• effects of the PURPLE cry intervention, compared to a control intervention, on fathers' neural responses to own infant cries compared to unknown infant cries

The investigators hypothesize:

• prior to the PURPLE material, fathers' neural responses to infant cry stimuli will be modulated by the following variables: subjective self-reported emotional reaction to cry stimuli, hormone levels, sleep quality and quantity, sex of the infant, infant temperament, life stressors, parental expectations, personality (neuroticism), and father's own childhood experience
• fathers who receive the PURPLE material compared to those that receive the control intervention will report a larger decrease in aversiveness and a larger increase in empathy in response to cry stimuli
• fathers who receive the PURPLE material compared to those that receive the control intervention will show a larger decrease in activity in the anterior insula and amygdala in response to cry stimuli
• fathers who receive the PURPLE material compared to those that receive the control intervention will show a larger increase in activity in regions of the brain important for emotion regulation, such as the dorsolateral prefrontal cortex (PFC) and orbitofrontal PFC
• fathers' neural activity in the amygdala in response to their own infant's cry stimuli will be positively correlated with both their own and infant testosterone levels

40 biological fathers of children age 2 months or younger who are currently cohabitating with the child's mother will be scanned on two separate occasions. The optional second visit will occur after 2 months have passed since the first scan. In the first visit, fathers will receive two MRI scans, one before and one after completing one of the two interventions. Prior to the MRI scan, a blood sample will be collected for measurement of hormone levels. Fathers will be positioned in the MRI scanner where they will receive structural and functional MRI scans of their brain while they listen to auditory stimuli: unknown cries, own cries, and tone controls. Blood sample collection and intervention will not be conducted during the second visit.

Inclusion Criteria:

• biological fathers of children age 2 months or younger who are currently cohabitating with the child's mother
• fathers with normal or corrected-to-normal (with contact lenses) vision

Exclusion Criteria:

• history of head trauma, seizures or other neurological disorder
• psychiatric illness
• alcoholism or any other substance abuse
• serious medical illness
• claustrophobia
• ferrous metal in any part of body