Weve come to the mainstay University Hospital to talk to dr michels its man a german specialist in the treatment of diseases that affect men hes also an expert on whole mines. Feeding out just astro is responsible for the development of a number of layoffs sickle characteristics including hair patterns on the head of it also determines beard growth affects muscles and a mans overall personality a system thats a much more complex or long term some people might think. Most testosterone is produced in the testes but a small amount comes from the adrenal cortex. This specific sources of testosterone of the light excels the hormones that are responsible for developing male characteristics in the body called androgens the most important antigen is testosterone. Levels of testosterone rise dramatically during puberty and then remain at a high level. But researchers have also found significant short term increases in this home and immediately after birth. Its hard to say why that happens but it seems to be a part of the maturation process in the brain and in the male reproductive system does better than most. Christian of all lives and brawn at the age of 20 he discovered that he had 2 little testosterone in his body doctors later determined that the cells in his brain were not sending up the proper production signals the cause of the problem wasnt clear. At 1st both had a hard time even describing the symptoms it took a long time for doctors to come up with a proper diagnosis. As far. As cancer realizing that something was wrong was a gradual process but it didnt happen overnight they kept feeling worse and worse i had no energy at all and no sex drive either spec mannish just one but i could feel something just wasnt right it was could feel that i was diagnosed with depression. Or when i realized that something was seriously wrong with make us all how to of course from a look up i went. Home was a medical student at the time and a bodybuilder he kept a close eye on his metabolism and testosterone levels. So it was a fluke but i couldnt figure out what was going on i got along well with my family and had a girlfriend i was doing well at school and then i figured out that this might have something to do with a testosterone deficiency in my vicinity interest of swan so i had some tests done and the levels turned out to be about 0 thats a bit low isnt a sense of any. How much testosterone demand actually need. To average men have at least 8. 00 to 12. 00 normals per liter of testosterone to anything below that represents a deficiency but the amount also depends on genetics a single misinformed if you need to convince testosterone levels are much lower food about 5 to 10 percent that ive met says they use the testosterone to synthesize estrogen to the primary female sex or along with. That synthesis is carried out by an enzyme called aromatase it can be found in cells in several parts of the body including the brain adrenal glands ovaries and testes. In the face of such testosterone levels christian fold chose a potentially risky form of medical treatment. That had. Needed hormone replacement therapy after other possible causes like vitamin d. Deficiency have been ruled out. One of the side effects of hormone replacement therapy is that it suppresses sperm production which can cause in particular. Mo here to cope with testosterone is naturally produced in the testicles but the process begins in the brain reciprocally in the hypothalamus sign and. Hides it links the bodys nervous system to the endurance system who the pituitary gland. The pitcher trade land is divided into 2 sections the anterior portion produces 2 key hormones l. H. And s. And each l. H. Is responsible for stimulating the production of testosterone in the testes. S. H. Contributes to the production of spam. These 2 hormones report back to the brain on within the body is producing enough testosterone and sperm. The brain adjusts the amounts of each as necessary. And it has to store testosterone replacement therapy suppresses the hormones in the pituitary gland that are responsible for sperm production and its like a Birth Control pills and a pillar for one month. And among other but if a man is testosterone deficient and wants to have children we have to take a different approach. Long testosterone can have serious effects on the body that can too much of its own mind make men overly aggressive. This is leon home of france the center for cognitive neuroscience says. Dreyer is a Research Director here. Has been studying the influence of testosterone on Human Behavior and hes found little evidence that to start strong stocks aggression in men. Should. Be a vector that testosterone has on Human Behavior is by no means clear but there is some indirect evidence that you know in the example high levels of testosterone have been found in some Prison Inmates who have committed serious crimes these are you more and we did a study which indicated that patients who were given testosterone injections if you could become more aggressive still in the fix you know you call to show. Your testosterone can also actually improve social behavior to. Some group or neutral it does seem to. So at this point theres little hard evidence pointing to a link between increased levels of testosterone and aggressive behavior. d dreyer conducted an experiment to try to prove or disprove these claims his 1st task was to measure the testosterone levels in the participants blood. Testosterone is a fat soluble hormone so it can pass through the membranes of cells bind with hormone receptors and then produce changes in the cell structure. Testosterone can be identified and measured in various bodily fluids. Including saliva urine and blood. Before the experiment begins one group of participants is injected with testosterone the other group is given a placebo. d to switch to an iron group and we try to determine whether the increase in testosterone levels would contribute to a change in behavior as you as graph shows that both groups started out with approximately the same level of testosterone was to actually look at the short that is then we gave one group of testosterone as jack shows its own severe mix and recorded the increase in the level of this hormone all. Now the test subjects are going to take part in a game exercise called ultimatum the game is frequently used in Behavior Research its designed to test whether a person is generous all selfish one of the players is given a sum of money and is required to share part of it with the other if the 2nd player accepts the offer the deal goes ahead as planned but if he rejects it neither player gets any money. At this point we observed no difference between the player whod been given testosterone and the one who hasnt is still into a city. Now the rules of the game are going to change a bit the players will be able to use the money to reward fair behavior or punish unfair behavior and this is where driver and his colleagues observed a difference between the player who got an extra dose of testosterone and the one who didnt. See obesity in his crew so true its a subtle difference and we confirmed it only in the 2nd stage of the experiment what can you with. The group administered with extra testosterone imposed a more severe punishment when they believed that they had been given enough money not in the same time they also reacted more positively when given more money than expected he did you know. We observed a big difference in the behavior of the 2 groups. So can testosterone also stimulate generosity in men the researchers was surprised by the results but the situation is more complex than that dre a says this is subconscious motivation at work. So much of young. This man aman and shows clearly that and so you can improve your social status if you cooperate with people or engage in other kinds of positive social behavior. Also more so while testosterone can influence aggression commitments which it also plays a role in the ability to act with generosity so thats good news in those 3. Dry eye has been looking for more evidence to support his theory on the influence of testosterone so hes been studying brain activity. The order to this is to a focus. Testosterone based behavior can improve a man social status and that process could be linked to various mechanisms in the brain its going to particularly a group of neural structures known as the reward system to mark. Improved social status generates a sense of wellbeing like a reward that may explain the boasting trait commonly associated with excessive manly behavior. You know its about something one of 2 guys theres always a motivation behind generosity you know if someone sees you being generous theyre more likely to think highly of you for example that men will probably be more generous if they know that they are being observed by women. Simply by them she dont buy them cubes this indicates another link between testosterone and generous behavior. This is to oprahs really was nothing that was to. So testosterone may be responsible for positive and negative behavior in both cases this behavior seems to be directed at preserving or even improving social status. Psychologist pronto mehta is an associate professor at University College in london. His research focuses on how hormones particularly testosterone influence Human Behavior. The evidence for that myth that testosterone is directly related to masculine traits like aggression has not borne out in the data so there are plenty of results suggesting that testosterone is either weekly or unrelated to aggressive behavior at all in humans including human males so the field is still trying to unpack these kinds of the facts to understand when testosterone might be related to other behaviors like helping and prosocial behavior as well the metal has carried out an experiment that involves the ultimatum game similar to the one we saw early on. Its actually a way to look at 2 kinds of behaviors one is trust to what extent is the 1st mover trusting and 2 to look at reciprocity of trust if someone is hyper trusting is the 2nd mover going to reciprocate that trust. As in the experiment carried out by sean claw dreyer one player was given an extra dose of testosterone the other player was given a placebo. The experiment will measure the level of trust between the 2 the player administered testosterone could use his money to make sure that the other player also profits that will the 2nd player give back some of his winnings as a gesture of gratitude or would he keep it all for himself. We found 2 interesting facts 1st is consistent with the stereotype testosterone reduce trust in the 1st mover so that is somewhat consistent with the stereotype being related to. Competitiveness and threat and the environment may be. Mobilizing more selfish social behaviors rates are going to keep money. Next the player has reversed their roles. In both tests the player with the extra testosterone shares his winnings with the other this is an example of prosocial behavior. We know that reciprocity even cooperate of situations where its going to garner status and what we found is it has altered boosted routes across city and were arguing that in a cooperate of environment its again a superstition prosocial behaviors that you claim status and so though in those situations saturn actually might prosocial. Matter is convinced that to stop steroid implies a much more complex role in Human Behavior than research has previously thought for example we can promote socially positive behavior but theres always a motivating factor behind that behavior. You can imagine when we think about our leaders and people in positions of power they have expertise knowledge and experience that theyre going to relate to their subordinates thats part of being a good leader thats also part of some definitions of power where youre helping others as a way to influence others in some ways so you could think of it as process but its also in some definitions an exertion of power. But concepts such as masculinity status and power are perceived differently in various cultures around the world will the test results differ from one country to the next. So of my laboratories and one in someone elses laboratory in germany someone elses laboratory the effects of testosterone on the human body at the same regardless of culture and geography when Christian Vall found out that he was infertile he started looking for solutions. But my mother took me to see a urologist only and he told her that i would never have children or that i could have a super would have sex life so my mom didnt think it was funny so i started reading up on my condition it is in the stream of lives of folks or. Is there a medical solution to infertility caused by testosterone deficiency. Doctors its my office somehow. When im. Out and licensed and one of the things we can do for men who suffer from this problem is to give them injections of going out on truckin hormones so they have a gun during which you can see how p. C. Form of treatment has been used for years even decades where you had seemed and comes. The good not a trope ans include l h which is responsible for the production of testosterone in the testes and if s. H. Which contributes to the production of sperm. The treatment was successful for christian of all for his body was able to produce testosterone and fish are sperm for a short period of time he had the sperm frozen for later use. Based on what stood out so if i had listened to what the doctors told me at 1st it would have ended right there but now i can have children 100. 00. 1 of the szell ties is a professor of psychology at Friedrich Alexander university in ellen his Research Work focuses on how testosterone affects the body specifically bone growth. One can be that would not go on doing some effective from. Just asteroids and extradite its counterpart in females and contribute significantly to bone strength and density action from Prenatal Development to maturity of your own destiny incumbents in the. Clear example during the 1st 3 months of pregnancy testosterone causes the ring fingers of the male foetus to grow longer than the index fingers in the sling fingers. Showtimes notes that in general womens index fingers are longer than they ring fingers in many its just the opposite. Here you can see that in this image of a mans hand. In the extreme is clearly shorter than the ring finger that. Because. Testosterone clearly has an influence on bone growth even in the early stages of pregnancy it might also be responsible for the Early Development of the socalled power motive. Shawn so this is as a scientist so im interested in finding out where that motive comes from i suspect that its origins can be found in biology is that were out. Here is conducting an experiment in which the participants write a fantasy narrative this may help them to determine whether they are motivated by power. Or the power motive is a common human characteristic that involves one persons efforts to have an impact on the behavior of others this motivation does not necessarily manifest itself a conscious attitudes or the beliefs that we have about ourselves our Research Indicates that the way we perceive ourselves actually has little to do with what makes us tick and what influences our spontaneous behaviors. Which for. This part of the experiment involves a series of 10 tests and finding out how the participants respond to victory or defeat. The test results can be manipulated one participant can win up to 8 of the 10 rounds. The researchers want to find out whether any changes take place in the test subjects hormone levels. To that we found that the power motive plays a role in the response to winning or losing. Those who won this had higher levels of testosterone than those who lost to them for the. And if one of the participants is not motivated by power but wins it has no effect on the amount of testosterone in his system. We cant say that winning or losing is exclusively responsible for changes in testosterone levels we have to take into account factors such as the individuals personality and motivation the fortunes of. Those factors are shaped by testosterone during fetal Brain Development. But does it all come down to testosterone and its influence in determining for example male finkle length and the development of the power motive. Women have only 10 percent of the testosterone levels found in men does that mean that they are less motivated by power. By play theres evidence that indicates that there is a connection between the length of womens fingers and the power motive complex business i was not so its a complex situation that will require a lot more research. Scientists have learned more in recent years about female sex hormones but the relationship between women in power has not been widely studied. The field has focused on male reproductive system and males for the past 100 years and has largely ignored collective looking at female sex hormones in the context of status and leadership and this is. This is a large gap in the literature to date. Weve come to the university of cambridge to talk to clinical psychologist simon baron cohen. Part of his research focuses on how gender affects Human Behavior in general and the brain in particular. Weve been looking sex differences in the mind between males and females on average and one of tests that we use is where you have to find a shape thats hidden in a design as quickly as you can and we find that on average man are faster at finding this target hidden in the overall design. Baron cohen and his colleagues conducted behavioral studies of children and. Since they started by testing hormone levels in numerous samples of amniotic fluid the liquid that helps protect the fetus in the womb. Weve measured the testosterone during a pregnancy in the womb in the amniotic fluid so this is the baby in the womb and some women during pregnancy have a clinical procedure called amniocentesis where a needle goes into that fluid to take up some of the fluid and we can measure testosterone in the fluid and babys very in terms of how much of the home and they are exposed to so boys share more and more testosterone than girls in the new york influence. In the early stages of Fetal Development the genitalia show no signs of gender distinction but after approximately the 7th week of gestation a gene on the y. Chromosome can activate a process that results in the development of testicles lyta testosterone plays a role in the development of masculine characteristics in several parts of the male fetus including the brain. While looking at these long term the facts of the hormones presumably mediated