Hormonal and behavioral changes in young adult heterosexual men during competition for a female partner: hormonal and behavioral analyses
Abstract
Men modify their behavior during interaction with a desired partner and in competition with other male suitors. For example, para-verbal behavior - deeper voice, and nonverbal behavior - more dominant posture and gestures communicate high status.
Male hormonal profiles are also expected to change in the context of mate competition - specifically, increases in testosterone (T) and cortisol (C). To test this, we developed a scenario where young adult men (aged between 16 and 18 y.o.) competed over a potential romantic date with a female - 10 young adult women (aged between 15 and 17 y.o.).
Each male recorded a short (~1 minute) introductory video, which was later used for analyses of nonverbal behavior. Participants were then exposed to situation a) win (chosen by female) and b) loss (rejection in favor of a rival).
Hormonal analyses (T and C from saliva assays) as well as vocal displays (pitch and intensity) were measured following each situation and compared to pretest baseline levels. Nonverbal displays were analyzed using InterAct software; behavior was coded for length and frequency.
Preliminary results appear to show the modulation of male voices with respect to the competition situations -lower pitch voice following the win situation and higher pitched voice after rejection. There appears to be an effect of vocal intensity - male voices are louder following the win situation and quieter after rejection.
We also found that nonverbal displays associated with dominance correlated with T levels. C levels correlated with friendly nonverbal displays but did not relate to nonverbal displays associated with dominance or stress.
These results suggest that there may be specific behavioral and hormonal patterns associated with courtship situations; dominance displays unsurprisingly relate to testosterone but friendly displays were unexpectedly related to cortisol. Ethical issues will be discussed.