Testosterone Promotes ‘Cuddling,’ Not Just Aggression - Neuroscience News

Summary: While more commonly associated with promoting aggressive behaviors, testosterone can also promote social affection and prosocial behaviors in males, a new study on gerbils finds.

“For what we believe is the first time, we’ve demonstrated that testosterone can directly promote nonsexual, prosocial behavior, in addition to aggression, in the same individual,” says Aubrey Kelly, Emory assistant professor of psychology and first author of the study.

Both scientists are trying to get at the question of how hormones work in the brain to allow an animal to rapidly change its behavior, depending on the social context.

Kelly and Thompson wondered if maybe testosterone might, in lockstep with being able to increase aggression toward intruders, also generally dampen prosocial behaviors.

“Instead, we were surprised that a male gerbil became even more cuddly and prosocial with his partner,” Kelly says.

The friendly behavior abruptly changed, however, when the original male subjects were given another injection of testosterone.

The researchers theorize that because the male subjects experienced a surge in testosterone while they were with their partners, it not only rapidly increased positive social responses toward them but also primed the males to act more prosocially in the future, even when the context changed and they were in the presence of another male.

However, the second testosterone injection then rapidly prompted them to switch their behavior to become more aggressive, as appropriate to the context of a male intruder.

“It appears that testosterone enhances context-appropriate behavior,” Kelly says.

Testosterone, then appears to help animals rapidly pivot between prosocial and antisocial responses as the social world changes.

“We know that systems of oxytocin and testosterone overlap in the brain but we don’t really understand why,” Kelly says.

Rather than just flipping an “on” or “off” button to modulate behaviors, hormones seem to play a more nuanced role, Kelly says.

“So, learning how hormones like testosterone help other animals adjust to rapidly changing social contexts will not only help us understand the biological nuts and bolts that affect their behavior, but also predict and ultimately understand how the same molecules in human brains help shape our own responses to the social world around us.”.

“Beyond sex and aggression: testosterone rapidly matches behavioral responses to social context and tries to predict the future” by Aubrey Kelly et al

Beyond sex and aggression: testosterone rapidly matches behavioral responses to social context and tries to predict the future

Although androgens are widely studied in the context of aggression, androgenic influences on prosocial behaviours have been less explored

We examined testosterone’s (T) influence on prosocial and aggressive responses in a positively valenced social context (interacting with a pairbond partner) and a negatively valenced context (interacting with an intruder) in socially monogamous Mongolian gerbils

T also had persistent effects on prosocial behaviour; males in which T initially increased prosocial responses towards a partner continued to exhibit elevated prosocial responses towards an intruder male days later until a second T injection rapidly eliminated those responses

Together, our results indicate that T can facilitate and inhibit prosocial behaviours depending on social context, that it can influence prosocial responses across rapid and prolonged time scales, and that it affects oxytocin signalling mechanisms that could mediate its context-dependent behavioural influences