Explaining individual variation in paternal brain responses to infant cries

Abstract

Crying is the principal means by which newborn infants shape parental behavior to meet their needs. While this mechanism can be highly effective, infant crying can also be an aversive stimulus that leads to parental frustration and even abuse. Fathers have recently become more involved in direct caregiving activities in modern, developed nations, and fathers are more likely than mothers to physically abuse infants. In this study, we attempt to explain variation in the neural response to infant crying among human fathers, with the hope of identifying factors that are associated with a more or less sensitive response. We imaged brain function in 39 first-time fathers of newborn infants as they listened to both their own and a standardized unknown infant cry stimulus, as well as auditory control stimuli, and evaluated whether these neural responses were correlated with measured characteristics of fathers and infants that were hypothesized to modulate these responses. Fathers also provided subjective ratings of each cry stimulus on multiple dimensions. Fathers showed widespread activation to both own and unknown infant cries in neural systems involved in empathy and approach motivation. There was no significant difference in the neural response to the own vs. unknown infant cry, and many fathers were unable to distinguish between the two cries. Comparison of these results with previous studies in mothers revealed a high degree of similarity between first-time fathers and first-time mothers in the pattern of neural activation to newborn infant cries. Further comparisons suggested that younger infant age was associated with stronger paternal neural responses, perhaps due to hormonal or novelty effects. In our sample, older fathers found infant cries less aversive and had an attenuated response to infant crying in both the dorsal anterior cingulate cortex (dACC) and the anterior insula, suggesting that compared with younger fathers, older fathers may be better able to avoid the distress associated with empathic over-arousal in response to infant cries. A principal components analysis revealed that fathers with more negative emotional reactions to the unknown infant cry showed decreased activation in the thalamus and caudate nucleus, regions expected to promote positive parental behaviors, as well as increased activation in the hypothalamus and dorsal ACC, again suggesting that empathic over-arousal might result in negative emotional reactions to infant crying. In sum, our findings suggest that infant age, paternal age and paternal emotional reactions to infant crying all modulate the neural response of fathers to infant crying. By identifying neural correlates of variation in paternal subjective reactions to infant crying, these findings help lay the groundwork for evaluating the effectiveness of interventions designed to increase paternal sensitivity and compassion.

Bats distress vocalizations carry fast amplitude modulations that could represent an acoustic correlate of roughness

“…In humans, acoustic roughness is not specific to fearful screams. This feature also has been found in other harsh sounding vocalization types such as infant cries 3 . The same could be true for bats.…”

“…amplitude modulations (AMs) in the sounds uttered occurring at frequencies between 30-150 Hz 1,2 . In addition to naturalistic screaming, in humans, roughness is also found in infant cries 3 , in harsh sounds produced in musical compositions such as the opera and hard rock 4,5 , as well as in sounds used in artificial alarm systems 1 .…”

How stress can influence brain adaptations to motherhood

“…The anterior insula is a key region involved in emotional empathy and a mother’s ability to share the experience of her child’s distress. Therefore, while too little activation in this region can indicate a lack of emotional empathy, too much activation can lead to too-high levels of distress in a mother, which can in turn compromise the mother’s ability to respond to her child’s distress ( Li et al, 2018 , Musser et al, 2012 ).…”

Exploring the links between early life and young adulthood social experiences and men's later life psychobiology as fathers

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