Examining How Infant Interactions Influence Men’s Hormones, Affect, and Aggression Using the Michigan Infant Nurturance Simulation Paradigm

Abstract

Interacting with infants changes affect and hormones in adult men; do these interactions and their effects also influence aggressive responding? In the present study, we tested 96 men in the Michigan Infant Nurturance Simulation Paradigm (MINSP) using a simulated infant (SI). Men provided saliva samples and responded to baseline questionnaires about health and affect, and then engaged in one of four randomly assigned conditions: neutral, audio cries (taped from infants), SI-R (responsive: (where the SI could be nurtured in ways that ended its crying), and SIN (nonresponsive: where the SI could be nurtured, but its crying could not be ended). After this, they viewed a neutral film video as a time filler, and then engaged in an aggressive responding task. Our results showed that hearing audio cries increased testosterone relative to baseline and the other conditions, and that the SI conditions increased negative affect relative to the other conditions. We found that the audio cries condition elicited more aggressive responding than the other conditions, but only marginally so. However, the hormonal changes were not associated with different patterns of aggressive responding. Results are discussed in light of biopsyschosocial pathways from nurturant and challenging infant interactions to psychological, hormonal, and behavioral outcomes.