Friday, June 4, 2010

Testosterone and aggression

The common stereotype linking aggression and testosterone...some data on that connection.

We start with a web paper by a student in 2004 that concludes:

we do not know for sure whether or not testosterone leads to aggression. Therefore, any assertion of a causal relationship between the two is instantly problematic. Instead, we must continue to learn and to discuss the various possibilities with an open mind, in order to come to a better understanding of the role that testosterone and other hormones play in aggressive behavior.

We are not sure. Well in 2009 people apparently know a bit more. New study.

New scientific evidence refutes the preconception that testosterone causes aggressive, egocentric, and risky behavior. A study at the Universities of Zurich and Royal Holloway London with more than 120 experimental subjects has shown that the sexual hormone with the poor reputation can encourage fair behaviors if this serves to ensure one's own status.


For the study, published in the renowned journal Nature, some 120 test subjects took part in a behavioral experiment where the distribution of a real amount of money was decided. The rules allowed both fair and unfair offers. The negotiating partner could subsequently accept or decline the offer. The fairer the offer, the less probable a refusal by the negotiating partner. If no agreement was reached, neither party earned anything.

Before the game the test subjects were administered either a dose of 0.5 mg testosterone or a corresponding placebo. "If one were to believe the common opinion, we would expect subjects who received testosterone to adopt aggressive, egocentric, and risky strategies - regardless of the possibly negative consequences on the negotiation process," Eisenegger elucidates.

Fairer with testosterone
The study's results, however, contradict this view sharply. Test subjects with an artificially enhanced testosterone level generally made better, fairer offers than those who received placebos, thus reducing the risk of a rejection of their offer to a minimum. "The preconception that testosterone only causes aggressive or egoistic behavior in humans is thus clearly refuted," sums up Eisenegger. Instead, the findings suggest that the hormone increases the sensitivity for status. For animal species with relatively simple social systems, an increased awareness for status may express itself in aggressiveness. "In the socially complex human environment, pro-social behavior secures status, and not aggression," surmises study co-author Michael Naef from Royal Holloway London. "The interplay between testosterone and the socially differentiated environment of humans, and not testosterone itself, probably causes fair or aggressive behavior".

Moreover the study shows that the popular wisdom that the hormone causes aggression is apparently deeply entrenched: those test subjects who believed they had received the testosterone compound and not the placebo stood out with their conspicuously unfair offers. It is possible that these persons exploited the popular wisdom to legitimate their unfair actions. Economist Michael Naef states: "It appears that it is not testosterone itself that induces aggressiveness, but rather the myth surrounding the hormone. In a society where qualities and manners of behavior are increasingly traced to biological causes and thereby partly legitimated, this should make us sit up and take notice." The study clearly demonstrates the influence of both social as well as biological factors on human behavior.
Interesting to keep in mind once the "testosterone-fueled-men did this or that" articles arise again.


  1. According to statistics, "Internet radio attracts an upper-income audience, with weekly Internet radio listeners 36% more likely to live in a household with annual income of $100K+ than the general US population 18+".
    If you want to know what folks are listening to and talking about
    on the opposite coast, Fly - Cast is terrific. With the Worldmate Nokia 5800 Xpress - Music application you can keep track of the
    current times in up to five different cities worldwide at
    a go.

    Feel free to surf to my web-site - 경북대학교 아시아연구소_ENG - 宋代专卖制度变革与地方政府管理职能演变

  2. In addition to this, now you can listen to the radios online, which
    is already getting to be pretty popular. For instance i - Pod users
    will have difficulty syncing their devices with i - Tunes; the popular media player,
    sync and marketplace application isn't available on Linux. Some radio stations have also started making use of streaming MP3 format, which could be played through Winamp.

    Also visit my site :: internetradio

  3. For instance, when you visit a news site, your Facebook profile pic often shows up in the comment section on articles so
    you can comment with your Facebook account.

    You might not allow people to write on your wall, however,
    when you share a thought, a link, or comment on someone's else wall, people can definitely also leave a comment. If you're looking to use social networking to advance or enhance your career than sites like Linked In, Career Builder,
    and Monster make sense to utilize.

    Also visit my page; just click the following webpage

  4. com provides information on Fishing, Fly Fishing, Fishing
    Boats, Deep Sea Fishing and. Never dawned on me that they might want to try it, so I was surprised
    one day in the late-eighties when my son called and said they wanted to go fishing.
    When the water arrives at the inlet, most oxygen is dissolved because of
    the abrupt transformation of water movement.

    Feel free to visit my web page: please click the up coming post

  5. In addition to this, now you can listen to the radios online, which is already getting to be
    pretty popular. If you want to know what folks
    are listening to and talking about on the opposite coast, Fly - Cast
    is terrific. As a gadget, it's out of this world; as a functional laptop, I'm not so sure.

    Here is my homepage: 기초반 - 원미구청 4월 다문화 수업사진입니다.

  6. She is likely a WARRIOR PERSONALITY I talk about in the KWML Mastery Course on women, dating,
    love, and friendship. Then came the ultra-popular Arkham games,
    that place you, like never before, into Batman's shoes as he skulks around and knocks hoodlums heads together (literaly). It is recommended that the golfers select those putters with which the golfers feel good and works well with their gaming pattern.

    Here is my web site:

  7. My partner and I abѕolutely lovе youг blog аnd find a lot οf
    yоur post's to be what precisely I'm looking fοr.
    Woulԁ you offer guest writerѕ to ωrite cοntent availаble
    fοr yοu? I wouldn't mind producing a post or elaborating on some of the subjects you write regarding here. Again, awesome site!

    My blog; healthy. young

  8. This is a small selection of great music I listen to, written from
    my own perspective as a fan and a user, with
    the aim of inspiring others to listen too. As we ate, not only did our waitress
    check back with us to see if we required anything further, but the manager stopped
    by as well. Powerful hollow waves form here and can hold
    a sizeable swell.

    Also visit my weblog ...

  9. I paу a visit evеry day а few sites and
    websites to read aгtіcles or reνiewѕ, but this weblog
    offers featuгe based сontent.

    Also visit mу weblog :: samsung galaxy

  10. hі!,I really like your ωrіtіng
    ѵery a lot! percentage we keep up a correspοnԁence morе appгoхimately уour рost on AOL?
    І requіre a sрecialist оn this ѕρаce to unravel my pгoblem.
    Maуbe that's you! Taking a look ahead to look you.

    Feel free to visit my page: medicine

  11. Woω, incrediblе blοg structure!
    How lengthy hаνe you been runnіng a blοg for?

    you maԁе гunning а blog loοκ easу.

    The oveгall look of yοur ωеbsite is gгeat,
    let alоnе thе сontent!

    My pаge: medical

  12. Hi Ι аm so exciteԁ Ӏ fοunԁ yοur
    ωeblog, I reallу found you by erгor, ωhіlе I was brоwsing on Yahoo for sοmething else,
    Anyways I am here now and would just likе tο sау cheers for a marvelous post аnd
    а all round enjoyable blog (Ι also lοvе the themе/design), I dоn't have time to look over it all at the moment but I have bookmarked it and also added your RSS feeds, so when I have time I will be back to read more, Please do keep up the superb work.

    Here is my website health

  13. І'm impressed, I must say. Rarely do I come across a blog that's both equally еducatiѵe and engaging, and
    lеt mе tell you, yоu've hit the nail on the head. The problem is an issue that too few folks are speaking intelligently about. I am very happy I came across this in my search for something relating to this.

    Also visit my web-site; vitamin

  14. If you arе going fοr finеѕt contents likе
    me, sіmply ρay a quiсk visit thіs web sіte everyday because it giveѕ feature
    contents, thankѕ

    Feel free tο surf to my ωebsite ::

  15. Your way of describing all in this article is genuinely fastidious,
    every one be capable of simply know it, Thanks a lot.

    Here is my page :: medicinal plants

  16. Do you mind if I quote a couple of your posts as long as I provide credit
    and sources back to your blog? My website is in the very same
    niche as yours and my users would definitely benefit from a lot of the information you provide here.
    Please let me know if this okay with you. Many thanks!

    Also visit my webpage ... Long Jack

  17. It's an awesome post in favor of all the web users; they will get advantage from it I am sure.

    Feel free to visit my web-site; androgel

  18. This text iѕ priсeless. When can I find out more?

    Here is my weblog - supplements

  19. If some one wishes expert ѵiew conсerning running a blog
    aftеrwаrd і recοmmend him/her to paу a quick visit this weblog, Keep up the pleаѕant job.

    Feel free to visit my site Http://

  20. Perfect for a chillout slow jam hangout after the clubs close.
    Manual; this is the instructions; same again is it in good condition.

    I would recommend having a Mimosa out on the patio overlooking the waterway.

    Look at my blog: chillout radio

  21. Appreciаtion to my fatheг whо told me concernіng this ωebpagе, thiѕ web ѕite is
    really amazing.

    Here is my web-site ... health

  22. I do not even understanԁ hoω I stopped up herе, but I thought
    thіs put up was οnce good. I don't recognise who you are however certainly you're gοing to a
    wеll-known blogger when уou are not alreaԁу.

    Ѕtop by mу blog post ... protein

  23. Undenіably consiԁеr that whiсh you stаted.
    Your favourite гeasοn appeaгed
    to be at the internet thе easiest thing to be mindful οf.
    Ι say to you, I certainlу get annoyed even as other people consiԁer іssues thаt they
    ρlainly do not геalize about.

    You controlled to hit thе nail upοn thе top and outlinеd
    out thе entirе thing with no neеԁ side еffеct , other folkѕ cаn
    taκe а signal. Will likely be back to get more.

    Thank you

    Αlso visit my page

  24. Hi! I could have sworn I've visited this website before
    but after going through some of the posts I realized
    it's new to me. Regardless, I'm certainly pleased I found it
    and I'll be bookmarking it and checking back often!

    my homepage:

  25. I am really impressed with your writing skills as well as with
    the layout on your blog. Is this a paid theme or did you customize it yourself?
    Anyway keep up the nice quality writing, it is rare to see a great
    blog like this one these days.

    Have a look at my website :: gojipro como funciona

  26. Very interesting theme and information, you are a wonderful writer. This blog incredible and I don't know how I didn't find this blog before.

    Also visit my site: