05 Април 2006 00:06

А бе и за онази работа така разправят, учените де, ама я питай женорята...

05 Април 2006 00:42

Абе, има ли тук чувство за хумор
А?
Ако няма рецептата е съд, ДО ДУПКА и в СтрасТбург задължително-
та това е чист расизъм и непозволени ектраполации

05 Април 2006 01:34

Мдаа, а може ли да се опитомяват хора? И след колко поколения започват да въртят опашка и да скимтят като питомни кучета?

05 Април 2006 01:44

Или, както казва един мой познат: ЖЕНАТА НЕ Е КАТО ЧОВЕКА!!!

05 Април 2006 01:52

ЖЕНАТА е най-добрият приятел на ЧОВЕКА наистина

05 Април 2006 03:04

Всичко в тази статия е голата истина такава каквато е!!!Би могло само да се добави за нещо и за Циганските и Турските Мюсолмани за техните мозъци които са изследвани и научно е доказано че някой Мозъчни Гънки сред техните мозъци липсват и което се доказва защо сред техните общности няма известни Учени и хора на изкуството и културата!!!Само Чалга и Цигански кючеци се въртят из техните мозци което го имат за Култура според техните разбирания!!!

05 Април 2006 05:11

Ей, ало, подложена на въздействието на източник на топлина, водата става... топла, ОК. Това - по адрес на последния си брой сп. "Нейчър".
А за скъпата ни СЕГА - чичо Доктор или някой друг от професията да помогне - не е ли малко подозрителна и симптоматична тая обсесия на редакцията напоследък с големината на мозъка и дебелината на интелекта

05 Април 2006 05:35

Колкото е по малък мозака и набръчкан е по умен от големия и изшлаифан.

05 Април 2006 06:44

Моабети. Нищо засега не е доказано.........

05 Април 2006 08:02

1. ...изложбата "Тела". Тази изложба гостува и в Хюстън въпреки протестите на някои местни консерви. А протеста беше заради това, че телата и органите са на истински хора, т.е. не изкуствени. За мен поне, беше интересна.
2. Светло Пиво, този път се изказваш много ангро. Не всичко, но много работи са открити. 3. Yapayapa, имаш предвид, че ни управляват хора с предимно малки главета? Главите им са малки, но обръчите им били големи казват. И портмонетата им дебели. Иначе директно по темата: казвали са ми жени, че е по-важно да е интелигентен, т.е. дебел, когато влиза по първо направление и по-дълъг, но не чак толкова дебел, когато влиза през задния двор. А ако се поема устно важното било да е бил главест. Ако го изпира на ръка е било важно да е венозно разширен. Във всички случаи обаче предпочитали да има повече бяло вещество и по възможност да го фурга. Става въпрос за мозъка, нали така?

05 Април 2006 08:11

Абе, кой ти гледа мозъка на жената, я виж Кондолиза Райс, кви ги дъни, с по-малко мозък, ама държавен секретар на САЩ...То, ако всичко става с мозък, досега да се е оправил света, ама нейсе...

05 Април 2006 12:04

Това, че мъжете били опитомили жените, си е чиста химера. Хилядолетните усилията са напълно безполезни.
Сравнението на жените с домашните животни обаче не е без основание.
Точно като при повечено домашни любимци етологията на поведение
е отработена много добре с цел да улесни паразитното преживяване.

05 Април 2006 12:21

Верна е статията...мойта жена докато я опитомих колко пари хвърлих...
Обаче виждам, че резултата е нетраен и трябва да продължа с опитомямането...

05 Април 2006 16:27

>>><<<
Гнусна екстраполация, експериментите са с лисици и евентуално могхат да се прилагат към жени, но без да се набъркват домашните животни.....

05 Април 2006 17:24

Глупости - измежду всички живи същества (с едно две изключения) човекът има най-голям мозък!!!!
Не може размерът на мозъка да не оказва въздействие върху интелигентността при това положение - то не е случайно.
А що се каса е до жените и мъжете - не е много ясно.
размер на мозъка при мъжа - 1250 грама
при жената - 1100 грама
при горилата - 1000 грама
???????????????????????????

05 Април 2006 22:40

e тва е статията: News

Nature 440, 588-589 (30 March 2006) | doi:10.1038/440588b
Scans suggest IQ scores reflect brain structure

Jim Giles


Research results reignite intelligence controversy.

Researchers say that a remarkable data set on the developing brain adds to the idea that IQ is a meaningful concept in neuroscience. The study, which is published on page 676 of this issue, suggests that performance in IQ tests is associated with changes in the brain during adolescence.
Unfortunately we are unable to provide accessible alternative text for this. If you require assistance to access this image, or to obtain a text description, please contact npg@nature.com



Children who perform differently in IQ tests show different patterns of brain development.

Claims that IQ is a valid measure of intelligence tend to attract angry responses, in part because of studies that have attempted to link group differences in IQ with race. In their 1994 book The Bell Curve, political scientist Charles Murray and psychologist Richard Herrnstein argued that the lower-income status of some US ethnic minorities was linked to below-average IQ scores among those groups. These were in turn attributed to mainly genetic factors.

Before that, Harvard University entomologist Edward Wilson provoked outrage with work that proposed evolutionary explanations for human behaviour and individual differences in intelligence; critics called the work racist. And this month, the journal Intelligence printed an editorial note defending its policy regarding the publication of controversial papers. The note comes after a study linking IQ and skin colour (D. I. Templer and H. Arikawa Intelligence 34, 121–139; 2006), published online last November, prompted a string of complaints from scientists.

Yet researchers studying IQ say the social climate is becoming more receptive to such studies, in part because it is now widely agreed that cognitive abilities are shaped by environmental factors as well as genetic ones.

The latest result, from a team led by Philip Shaw at the National Institute of Mental Health in Bethesda, Maryland, adds to the debate by linking IQ with changes in the brain over time, rather than fixed attributes such as brain size. "It's not that brainy children have more grey matter," says Shaw. "The story of intelligence is in the trajectory of brain development."

Shaw's team tracked a group of more than 300 children as they aged from 6 to 19, running them through a series of cognitive tests — IQ is determined by combining scores from tests of a range of verbal and non-verbal abilities. The team also measured the size of brain structures using magnetic resonance imaging at roughly two-year intervals: more than half the children had at least two scans, and around a third were scanned three or more times.

When the researchers split the children into three groups according to their initial IQ scores, they noticed a characteristic pattern of changes in the brains of the group with the highest scores. The thickness of the cortex — the outer layer of the brain that controls high-level functions such as memory — started off thinner than that of the other groups, but rapidly gained depth until it was thicker than normal during the early teens. All three groups converged, with the children having cortexes of roughly equal thickness by age 19. The strongest effect was seen in the prefrontal cortex, which controls planning and reasoning.

"My first impression was 'wow, this is amazing," says Jeremy Gray, a psychologist at Yale University in New Haven, Connecticut. He notes that it is difficult to persuade children and parents to return for scans over a long period of time, so imaging studies are usually limited to tens, rather than hundreds, of subjects.

Shaw's study raises questions that could prompt further research. His team did not look at what could be causing the changes in cortical thickness, for example; the group points out that several mechanisms — including the formation and elimination of connections between brain cells — could be responsible. Also unknown is how genetic and environmental factors contribute to the change.

The study is likely to prompt discussion of the possible social applications of such results, but these are limited. The trend identified by Shaw was significant when results from all the subjects were combined, but would probably be too small to predict how an individual child is likely to fare in school, for example.

There are also likely to be queries about whether the research should have been conducted in the first place. IQ is a good predictor of performance at school and in the workplace. For some neuroscientists, this makes the physiological factors that contribute to IQ worth studying, in order to probe how intelligence works. "There's good evidence from functional imaging studies that very demanding tasks activate the prefrontal cortex, and that activity correlates with IQ," says Shaw. "We're getting at some common processing resource."

05 Април 2006 22:44

e тва е една друга ако някои се интересува
News and Views

Nature 438, 31-32 (3 November 2005) | doi:10.1038/438031a
Intelligence: A gender bender

Steve Blinkhorn1

Abstract

The conclusion of a number-crunching exercise on various data sets is that male university students have significantly higher IQs than their female counterparts. But the methodology used is deeply flawed.

"Finding bad reasons for what we believe on instinct" is how the philosopher F. H. Bradley famously defined metaphysics1. Meta-analysis — the deployment of statistical methods on a range of other people's research results to draw stronger conclusions than any individual study can bear — is in jeopardy of coming into that kind of disrepute when it is treated in the manner of a paper just published in the British Journal of Psychology2.
Unfortunately we are unable to provide accessible alternative text for this. If you require assistance to access this image, or to obtain a text description, please contact npg@nature.com


The paper is by Paul Irwing and Richard Lynn, and was widely trailed in the British press at the end of August. It claims to show an average IQ advantage of 4.6 points in favour of males among university students — about one-third of the standard deviation of IQ in the population as a whole, which by convention is set at 15. If this were true, it would really matter, in a way that resonates with the recent controversy at Harvard University concerning the representation of women in science3. It would also overturn a consensus of more than 50 years' standing, that the only sex difference in IQ is a possible slightly greater variance among males.

The prospect of further controversy focused on gender politics and the shortfalls of IQ tests does not seem remote. But the real discussion should concern whether this paper stands up to scrutiny. It does not.

The authors chose to investigate sex differences in scores on two versions of Raven's matrices, the standard and the advanced. These are great survivors among intelligence tests, being still widely used in the same form around 60 years after they were developed. Their particular claims to fame arise from the fact that the content is entirely diagrammatic (and so, according to some, less culturally biased), and from the results of factor analyses that suggest the ability they tap is close to pure g, variously called general intelligence, fluid intelligence or the ability to learn.

Irwing and Lynn searched the literature for studies on university students that reported average scores by gender. They found 22, with sample sizes ranging from 30 to more than 9, 000, publication dates from 1964 to 2004, and locations as various as Egypt, India, Mexico, Belgium, Australia and the United States — but curiously nothing from Britain where the tests were developed. For the most part, the purposes of the studies identified were not to investigate sex differences.

The number-crunching phase of the meta-analysis — weighting differences by sample size — resulted in an estimated difference of 0.15 standard deviations in favour of males. There are technical reasons for supposing that even this is an overestimate, but the authors go on to find reasons for not accepting this result. First, they exclude the largest study of all, an explicit 'norming' exercise in Mexico that accounts for almost 45% of the data, on the grounds that it is an 'outlier', with a difference of only 0.07 of a standard deviation — males answering on average only 0.4 more items correctly out of 60.

Abandoning the principle of weighting results by sample size, Irwing and Lynn then take the median of the estimated differences (0.31), and multiply it by the general-population standard deviation of IQ (15.0) to get the estimate of a 4.6-point IQ advantage for males. Before going on to speculate on the neurology underlying the female inferiority that they claim to have demonstrated, they propose that this result is "strong corroboration" of other meta-analytical results they have obtained for the general population.

It is nothing of the sort. The ten studies with estimated differences above the median cover a total of only 2, 591 participants, whereas the ten studies with differences below the median account for 15, 735 participants — the four largest differences come from samples of 111, 173, 124 and 300, the four smallest from samples of 844, 172, 9, 048 and 1, 316. Choosing to use the median is a flawed and suspect tactic.

But even going along with Irwing and Lynn's approach produces a different outcome if more plausible parameters are chosen. Whatever the standard deviation of IQ among university students, it is highly unlikely to be as large as 15, the conventional figure for the population as a whole. Raven's matrices, by design, tend not to produce normal (gaussian) distributions. An estimated standard deviation of 10 IQ points among students would ensure that there are not too many genuinely mentally defective undergraduates, even if some of them do have learning difficulties. This suggests a mean difference of up to around 1.5 IQ points — 10 times 0.15 (the figure weighted by sample size). Were a perfect study possible, with proper attention to sampling and motivational issues, I would expect even that to turn out to be an overestimate.

Raven's matrices have been widely used for decades, and it is likely that the 'file-drawer' effect is at work here — studies with no significant or substantial results never find their way into a journal, with no reporting of separate statistics for each gender when there is no difference. My own file drawer turned out to contain an analysis of data from 752 applicants for places on one degree course during the 1970s, tested on the advanced matrices, which were designed for the top 20% of the population. This yielded an advantage of 0.07 standard deviations for females. The sample is larger than all but five of those found by Irwing and Lynn. Should it be included in a meta-analysis? Of course not: the data were collected for another purpose and, without attention to purpose and context, meta-analysis is just numerical manipulation for its own sake.

Where there are sex differences to be found, detailed study of the internal workings of the test tends to show why. That's not based on instinct, but on my professional experience in designing gender-fair tests. Meta-analysis is not a substitute for properly designed research, and sex differences in average IQ, if they exist, are too small to be interesting.