Wednesday, 9 November 2005

Brains, Gender, Humour, Pain, and possibly Depression

A piece from the BBC from 2003 I hadn't noticed before :
Men and women's brains respond to pain differently, researchers have found.

Scans showed parts of women's brains linked to emotion were stimulated when they felt pain.

But the researchers, from the University of California Los Angeles (UCLA) found that, in men's brains analytical areas showed greater activity.
The UCLA researchers carried out positron emission tomography (PET) brain scans of 26 women and 24 men, while they experienced a small amount of pain.

Although there were some areas of the brain which were stimulated in both men and women, differences were seen between the sexes.

The female brain showed greater activity in limbic regions, which are emotion-based centres. In men, the cognitive regions, or analytical centres, showed greater activity.
Dr Bruce Naliboff, clinical professor of psychiatry and biobehavioral sciences, at UCLA, added: "The reason for the two different brain responses may date back to primitive days, when the roles of men and women were more distinct."

He suggested the gender differences may have evolved as part of a more general difference in stress responses between men and women.

Men's cognitive areas may be more highly triggered because they would have had to make "fight-or-flight" decisions, while women would have reacted to threats by thinking about how they could protect their children.
Interesting. My own panic reaction is to become icy calm, to analyse, and to think about how best to protect the ones I love, regardless of my own safety. It's only afterwards I collapse in a screaming heap.

And now this one, again from the BBC :
Scientists have uncovered hard evidence of a gender divide when it comes to appreciating humour.

A Stanford University team monitored brain activity when men and women looked at funny cartoons.

They found areas of the brain involved in language processing, memory and generating reward feelings were more likely to be activated in women.

It is hoped the Proceedings of the National Academy of Sciences study may provide insights into depression.
Lead researcher Professor Allan Reiss said: "The results help explain previous findings suggesting women and men differ in how humour is used and appreciated."

The prefrontal cortex, which is involved in language processing and memory, is known to play a role in humour appreciation.

And the Stanford team has shown that the mesolimbic reward centre - responsible for generating the positive feelings associated with events such as monetary gain - is also activated by humour.

The latest study used sophisticated scans to monitor the brains of 10 men and 10 women as they watched 70 black-and-white cartoons.

The researchers found similarities between the way that male and female brains respond to humour.

But some brain regions were activated more in women, including both the left prefrontal cortex and the mesolimbic reward centre.

The researchers say their findings suggest women place a greater emphasis on the language of humour, possibly employing a more analytical approach.

They also believe that the women in the study were less likely to expect the cartoons to be funny - so when they were, their pleasure centre lit up with greater intensity than their male counterparts.

Professor Reiss said: "Women appeared to have less expectation of a reward, which in this case was the punch line of the cartoon.

"So when they got to the joke's punch line, they were more pleased about it."

The researchers also found that the funnier the cartoon, the more the reward centre was activated in women.

That was not the case in men who seemed to "expect" the cartoons to be funny from the start.

Professor Reiss said the finding that women's reward centres might be more sensitive to emotional stimuli, if confirmed by follow-up studies, might explain why they appear to be more vulnerable to depression.

Professor Tonmoy Sharma, of the Clinical Neuroscience Research Centre in Dartford, Kent, said it was certainly the case that women were more likely to become depressed.

However, he told the BBC News website: "I would agree that women are much more analytical in terms of humour, but to extrapolate from this study, and draw conclusions about clinical depression is probably a step too far."
On a related note, there's a previous post of mine on gender-based differences in the brain, and depression.

I'd feel a lot more confident about the results and conclusions if the sample sizes weren't just in double digits.

An even more interesting thought occurs: how do transsexuals react? Do their brain functions correspond more closely with those of their self-dentified gender, or those of others sharing the same body morphology? There are certainly enough for a decent sample size. From Professor Emerita Lynn Conway :
Adding up the numbers of surgeries over these decades, we find that there are roughly 30,000 to 40,000 post-op transsexual women in the U. S. Of course some surgeries done by U.S. surgeons are on foreigners (perhaps 15%?). And some who've undergone SRS have passed away by now. However, the majority of post-op transsexuals had SRS within the past 15 years, and a high percentage of them are still living. TS's in the smaller group who underwent SRS in the 60's to mid-80's were mostly young - in their twenties and early thirties, and thus most of those women are also still alive. Even accounting for mortalities, Lynn estimates that the number of post-ops in the US is greater than 32,000.
Lynn estimates at least 3 to 5 times as many people suffer intense MtF transsexualism as those who have already undergone SRS. The reasons are obvious: Many transsexual people are unaware of the options and treatments for resolving the condition, and suffer in silence thinking there is no hope.
Tell me about it.
Many are terrified to "come out" and seek help for fear of social stigmatization. Many more are incapable of paying the high medical costs for transition. Thus there must be on the order of 100,000 to 200,000 UNTREATED cases of intense transsexualism in the U.S.
Based on personal experience - I believe her. In April this year, I wouldn't have appeared on the scope. I valued my marriage and my family far more than I valued myself, and anyway, it was impossible. It would have taken a miracle. I was born male, I would die male. Full stop, end of story.

The trouble is... no-one wants to do research on the subject. It's Taboo. It's also been hopelessly politicised. To some, it's a matter of Faith that it's a psychiatric condition. To others, it's seen as a "Lifestyle Choice" under persecution by the NeoCon Fascist BushHitler Zionazis. The Right doesn't want any research which would encourage such sicko freaks in their delusion. Many decent rightists' views on the subject are accurately expressed here
There is no such thing as a transsexual. There is no such thing as a man in a woman's body or a woman in a man's body. There are, however, some very sick people whose deep mental illness deserves our compassion and care. Any man who wants to have his genitalia surgically removed and some grotesque imitation of a female organ put in its place requires years of therapy and medication. Or, frankly, needs to put in a hard week's work fifty times a year so that he stops concocting neurotic nightmares and gets on with leading a meaningful life.
By the way, I've had some exceeding courteous e-mail correspondence with the author of that one, he's a thoroughly decent human being.

The Left distrusts Science, they're more comfortable with Pyramidology, Chakras, Spiritual healing and so on. Anything that might conceivably show that Transsexuality is a Psychiatric illness is forbidden. Because what next, a reversion to the old days where Homosexuality was a Psychiatric Illness? As for physical differences between the way that the different genders think, that is so politically incorrect, it's unnacceptable. What next, removing Female Sufferage?

Personally, if I'm Delusional, I'd really like to know that, OK? The evidence against that proposition, poor though it is, I find convincing: Transsexuality is a congenital abnormality, cause unknown, that results in a Female-pattern brain in a male body, or a Male-pattern brain in a female one. It's becoming pretty clear as we do more research that there are genuine differences in the way Men and Women think, and that these are related to cellular response to chemicals, neural arrangements, and even gross brain structures. That a minor hiccup could occur during brain development in the womb, perhaps caused by a hormonal glitch, or environmental factors such as administration of diethylstilboestrol during pregnancy seems very plausible. The more we know about gender differences in the brain, the more it seems that the existence of some degree of biologically caused transsexuality in the population is inevitable.

However... I'm not exactly objective here. I have too big an emotional stake in the issue to consider myself unbiased.

Then there's the peculiarity that some people with transsexuality have their body change underneath them, without treatment. Difficult to explain, that. But rare enough for it to be ignored, right?

No comments: