From Sarah, by email

Dear Carole, Please can you help me with an embarrassing problem which I can't seem to control that annoys my boyfriend (and my previous one too).

I'm in love with him, and he with me; we've been together for four

years. But I talk more than him and can't seem to stop myself, especially when I'm excited or happy, when he's just trying to quietly enjoy the moment.

It doesn't help that he's Hungarian. I have learned a few basics of his native language, but am nowhere near fluent and can't hold a conversation in Hungarian.

Do you have any advice to help me control my talking when I'm excited or happy?

Ask Carole: Chimpanzee wearing spectacles Photograph: Public Domain

Carole replies:

Evolutionary theorists have argued that the evolution of female sociability is linked to the development of the primate neocortex.1 This is the part of the brain responsible for language, sensory perception and self-awareness, among other cognitive abilities. (Neocortical abnormality is associated with autism and impaired communication skills.) The neocortex is proportionally larger in primates than in other mammals, larger in the apes than in monkeys and significantly bigger in humans.2

In addition, information transfer points between the brain's two hemispheres are larger in human females, thus facilitating rapid inter-hemispheric processing of linguistic and empathic information.3

It is thought that social evolution in primates has been female-driven and that females are selected for group co-operation.4 The idea is that those of our female primate ancestors who were communicative and co-operative breeders left behind higher numbers of descendants than those who did not communicate and co-operate.5

By around six months human infants start to babble and, depending on the sociability of the individual, this spontaneous chattiness may continue into adulthood. This is more likely to happen in females than males. Innate sex differences in brain architecture may give females the edge in social communication, though the difference is unrelated to measures of general social intelligence.

All of this research indicates that you, Sarah, and your ancestors have evolved to be chatty, babbling females. When primates become excited their vocalisations increase and you are no different. When you are in the company of like-minded female friends that isn't a problem. You can talk as much as you want, jump backwards and forwards between themes and sub-themes, and concurrently narrate multiple storylines. Your friends will happily reciprocate and no one will lose the plot.

But your hard-wired chattiness annoys the men in your life – men not hard-wired for empathic chattiness. You have reached a point now where you want to please your partner by controlling your spontaneous vocalisations. You are willing and perhaps able to adapt to his requirement for silence.

But here's your dilemma.

Many female primates only commune with males during sex, the rest of the time being spent in the company of females and infants. Males are often found sitting alone. By contrast, humans have developed a monogamous culture in which males and females spend social time together. Frequently men wish the females in their lives behaved more like males and women wish the men in their lives could get in touch with their feminine side.

Your personality type is most probably more socially flexible than your partner's, so it may be easier for you to quieten down than for your partner to reciprocate your need for constant chatter.

But at what cost? For an evolved, advanced social animal to deny this large part of herrself and metaphorically gag herself could lead to depression. Empathic humans have an innate requirement for companionship, shared experience and to listen and explore all points of view.6 It is a therapeutic necessity for babbling humans to be able to exchange chatter, and to analyse the crucial information held therein, rather than to experience emotional highs and lows in isolation.

As you are in love with your current boyfriend, however, you will not want to find a new, chattier male. Perhaps, instead, when you cannot be in the physical company of girlfriends you could simply phone or message them? That way you could continue to live out your excited, babbling happiness and your desire to share that happiness with others without irritating your partner.

You might also try purging your excited thoughts by writing them down.

Just don't forget that you have a duty to know your evolved self and keep yourself happy.

References

1. Lindenfors et al (2007) Primate brain architecture and selection in relation to sex. BMC Biology; 5: 20.

2. Dunbar, R I M (2007) Male and female brain evolution is subject to contrasting selection pressures in primates. BMC Biology; 5: 21.

3. Baron-Cohen, S (2003) The Essential Difference: Men, Women and the Extreme Male Brain. Penguin Press.

4. Lindenfors, P et al (2004) Females drive primate social evolution. Proceedings of the Royal Society B; 271(Suppl 3): S101–S103.

5. Hrdy, S (2009) Mothers and Others: The Evolutionary Origins of Mutual Understanding. Belknap Press.

6. Decety, J, Sommerville, J A (2003) Shared representations between self and other: a social cognitive neuroscience view. Trends in Cognitive Sciences. 7; 12: 527-533.

- This article was corrected on 27 July 2010. Reference 1 gave the wrong journal title for Lindenfors et al. This has now been corrected to BMC Biology.