Showing posts with label Intelligence. Show all posts
Showing posts with label Intelligence. Show all posts

Friday, September 23, 2011

Improving general intelligence with pharmacological intervention

From the journal Intelligence:
Cognitive enhancing substances such as amphetamine and modafinil have become popular in recent years to improve acute cognitive performance particularly in environments in which enhanced cognition or intelligence is required. Nutraceutical nootropics, which are natural substances that have the ability to bring about acute or chronic changes in cognition have also been gaining popularity in a range of settings and applications including the workplace, driving and in the amelioration of age related cognitive decline. Huperzine A, Vinpocetine, Acetyl-l-carnitine, Rhodiola Rosea and Alpha-lipoic Acid are popular nutritional supplements that have shown promising benefits in improving a range of biological (e.g., blood flow, anti-inflammatory, anti-oxidant, and direct neurotransmitter effects) and cognitive processes from in vitro, animal and human clinical research. We report here the first human randomized clinical trial for cognition in which we administer a combination of Huperzine A, Vinpocetine, Acetyl-l-carnitine, R. Rosea and Alpha-lipoic acid (called Ceretrophin) vs placebo. Sixty participants (40 females and 20 males, with a mean age of 45.4 years, SD = 12.6) completed either the odd or even items from the Raven Advanced Progressive Matrices (APM) at baseline and the opposite odd or even items at week 4 after consuming either the combination nootropic or placebo. A significant study visit (time) × treatment condition interaction was found: F (1, 57) = 7.279, p = 0.009, partial η2 = .113, with paired samples t-tests revealing a significant improvement in mean APM score from baseline to retest (week 4) (t(34) = − 4.045, p < .001) for the Ceretrophin™ group. Improvements in APM scores could be attributed to the active intervention over the placebo, indicating that the treatment improved general intelligence. Implications for improving our understanding of the biological basis of intelligence and pharmacologically improving human cognition are discussed.

Sunday, August 28, 2011

Richard Lynn's second revised edition of Dysgenics

From a review in the journal Intelligence of Richard Lynn's second revised edition of Dysgenics:

The second edition contains two new chapters. The first of these documents the decline of the world's IQ arising from the high fertility of low IQ populations worldwide, compared with the low fertility in high IQ populations. Lynn calculates that the effect of this is that the world's genotypic IQ is deteriorating by 1.3 IQ points a generation. Thus, genetic deterioration of intelligence is taking place both within and across counties.

The second new chapter is concerned with the effects of immigration on the intelligence of the populations of the United States and Western Europe. Lynn argues that most of these immigrants have lower IQs than the host populations and, hence, that as their percentages in the host populations increase, the IQ of the populations will inevitably decline. For the United States he adopts the estimate of the Bureau of the Census that in the year 2050 non-Hispanic whites will be 45% of the population. He calculates that this will entail a decline of 4.4 IQ points of the American IQ over the fifty-year period from 2000 to 2050.

Lynn argues that immigration will also bring about a decline of intelligence throughout Western Europe during the course of the twenty-first century. For Britain, he adopts Coleman's (2010) estimate that the indigenous population will decline to 56% of the population by the year 2056, and the other 44% will consist of largely of South Asians and Africans from the Caribbean and sub-Saharan Africa. He calculates that this demographic change will entail a decline of 2.5 IQ points over the fifty-year period from 2006 to 2056. He calculates that similar declines will take place throughout continental Western Europe.

Looking further into the future, Lynn argues that the percentages of non-Europeans in the populations of the United States and Western Europe will inevitably continue to increase in the second half of the twenty-first century and beyond as a result of their continuing immigration and higher fertility. He argues that this will entail further declines in the IQs of the populations.
Some readers may be disappointed that Lynn does not spell out the geopolitical consequences of this, perhaps because he does not want to appear too controversial, but it must be questionable whether the world leadership of the United States and Western Europe in science, technology and economic development can be retained as the IQs of the populations fall and the populations come to resemble those of most of Latin America, in which European peoples are a minority.

Tuesday, August 16, 2011

Human ability, sex, and intelligence

An interesting article by Gil Greengross and Geoffrey Miller:
A good sense of humor is sexually attractive, perhaps because it reveals intelligence, creativity, and other ‘good genes’ or ‘good parent’ traits. If so, intelligence should predict humor production ability, which in turn should predict mating success. In this study, 400 university students (200 men and 200 women) completed measures of abstract reasoning (Raven's Advanced Progressive Matrices), verbal intelligence (the vocabulary subtest of the Multidimensional Aptitude Battery), humor production ability (rated funniness of captions written for three cartoons), and mating success (from the Sexual Behaviors and Beliefs Questionnaire). Structural equation models showed that general and verbal intelligence both predict humor production ability, which in turn predicts mating success, such as lifetime number of sexual partners. Also, males showed higher average humor production ability. These results suggest that the human sense of humor evolved at least partly through sexual selection as an intelligence-indicator.

Wednesday, July 14, 2010

GSS respondents were asked to rate the intelligence of various groups, giving them a score somewhere between untelligent (1) and intelligent (7). The mean ratings given by blacks and whites are shown above (sample size = 1,230). 

Blacks and whites agree that Jews are the smartest.  It's reassuring to see that people aren't completely clueless about reality. Blacks think Asians are smarter than whites, but whites think that they are a bit smarter. Blacks view themselves as being almost as smart of whites; whites disagree. Whites consider Hispanics to be less intelligent than blacks--that surprises me--it's possible that the fear of looking anti-black is being reflected here. The fact that whites don't give southern whites a score much higher than blacks might reveal the ease with which so many whites look down on their brothers in the South. Blacks also think they are smarter than southern whites.  

So, whites overestimate their IQs relative to Asians, while blacks do so basically with everyone. They do think whites are smarter, but by only a trivial amount.

Wednesday, May 06, 2009

Do blacks rate themselves as athletic? In a previous post, I showed that blacks give themselves higher ratings on intelligence than whites or Asians do. Could this be due to reference group comparisons? People compare themselves to others they know in order to assess themselves. Perhaps the typical black person does not know someone nearly as smart as the average Asian person, so the black sees himself as being comparatively intelligent.

But it doesn't work in a context where blacks are arguably superior. The General Social Survey asked 2,373 Americans how athletic they were. The researchers are not too bright and gave the highest score to the least athletic (5) and the lowest score to the most athletic (1), so what you see is the mean unathletic score:

Mean unathletic score

Blacks 2.97
Whites 3.14
Others 3.13

Blacks think they are more athletic (although the difference is not huge). If my theory were correct, an average black person would probably know a better athlete than the typical white guy and would thus rate himself as being less athletic. But blacks are not doing this. They give themselves high intelligence ratings, and they give themselves high athletic ratings. Regardless of objective realities, their self-assessments are generous. For some reason, blacks are more positive about themselves than other groups. As I often show on this blog, the facts simply do not support the idea that blacks live in a country where they are systematically mistreated, run down, belittled, or made to feel inferior.

Wasn't self-esteem such a neat theory? On paper, it seemed to work perfectly. Blacks have always been treated as inferiors; they underperform; it's because they internalize the inferior label and act accordingly. Pretty neat. As is often the case with liberal creativity, the idea falls apart as soon as you look at the facts. "What's wrong with those blacks? Why do they feel so good about themselves? Damn, another theory down the drain."

Monday, February 09, 2009

A couple points about abortion and achievement: One argument made in the comment section of the last point is that smart, pregnant girls give up bright futures if they don't get an abortion. It is certainly true than teen motherhood makes it harder to have a successful career. Not impossible, but harder.

One currently popular belief is that if children are going to grow up to become well-adjusted adults, both mom and dad must devote every waking moment to their development. The best research tells us that this is simply not true. If kids were randomly assigned another pair of parents, they would turn out pretty much the same. Research also tells us that day care is not bad for children. So, to all you young women contemplating an abortion, it might be harder, but you don't have to kill your child to get ahead. You might have to give up spending as much time with the little guy, but trust me, if you're the ambitious type you'll enjoy your children more if you're not with them all day. Drop the idea that Junior needs you that much.

Another reader comment was that an intelligent, pregnant teen can always have kids later. While this is true, one demography truism is the longer you wait, the fewer the children you have. I looked at GSS data and found that a delay of ten years translates into one fewer kid for women with the highest IQ (WORDSUM) scores.

I'm not concerned about an overall lack of kids: I'm worried that we're having too many unintelligent kids and not enough smart ones. At the same time, it makes sense for a society to put its female talent to use. While there is tension there, challenging the notion that kids need mom 24/7 can help us achieve both goals.

Saturday, March 31, 2007

Intelligence and mental illness: Let's examine the old idea that smart people are more likely to have mental problems. Nietzsche went crazy, right--among others? The GSS asked people if they have ever had a mental illness, and here are their mean IQs:

Mean IQs--Whites

Mental illness 109.9
No mental illness 101.3

Mean IQs--Blacks

Mental Illness 100.1
No mental illness 94.4

For blacks and whites, those reporting having had a mental illness have higher average IQs. Once again, the data presented on this blog have a way of supporting stereotypes. Now, some will inevitably claim that smart people will admit their illness while less intelligent people won't, but you must admit the differences are quite large.

Thursday, February 22, 2007

IQ and residential mobility: Using General Social Survey data on more than 27,000 whites, I calculated average IQs based on vocabulary tests scores for each region of the country the person lived in when age 16, and by their current region of residence. I wanted to learn more about the residential mobility patterns of smart vs. dumb people. Here I list the top 10 smartest groups, followed by the least intelligent:

Top ten IQs by residential status:

1. MTN-->NE,* 123
2. ESC-->NE, 119
3. WSC-->MA, 118
4. PAC-->NE, 116
5. WSC-->NE, 115
6. SA-->NE, 115
7. WNC-->NE, 115
8. ENC-->NE, 112
9. ESC-->MA, 112
10. WNC-->MA, 111

Bottom ten

1. ESC-->PAC, 94
2. ESC--ESC, 95
3. ESC-->WSC, 96
4. WSC-->ENC, 97
5. PAC-->ESC, 98
6. ENC-->ESC, 98
8. ESC-->ENC, 98
9. SA--SA, 98
10. WSC--WSC, 99

*The first acronym is where you lived when you were 16; the second is where you are now.

NE=New England
MA=Middle Atlantic
ENC=East North Central
WNC=West North Central
SA=South Atlantic
ESC=East South Central
WSC=West South Central

So, the smartest groups moved to New England or the Mid-Atlantic, and were likely to come from regions far from the Northeast and with little concentration of cognitive elites of their own. The least intelligent groups either were born in the South and stayed put there, or either moved from the South or to it. The East South Central region popped up many times among the bottom 10.

Tuesday, February 20, 2007

Even more on IQ and crime: The discussion on the relationship between intelligence and illegality has been interesting. One reason, apart from the GSS data, why I'm skeptical about the claim that IQ is a powerful determinant of criminal behavior is that it does not pass my basic test for any theory of crime: is it consistent with the two risk factors we are most certain about--gender and age. Males are much more criminal than females, but they are not more stupid. Youthfulness is one of the best predictors of street crime, but IQ doesn't grow with age, rather it drops off slowly.

I was also interested in calculating the correlation between IQ and thinking that cheating on taxes is wrong (1=not all, 4=very wrong). It turns out to be .11 for whites, consistent with other analyses I have seen: the correlation is reliable but weak.

Monday, February 19, 2007

Weird Al Yankovic: It seems that Weird Al Yankovic has figured out how a white guy can say in an acceptable way what race realists are marginalized for saying: that whites, on average, are smarter than blacks, and that blacks are more likely to be street criminals.

White and Nerdy (a rap song)

You see me mowin' my front lawn
I know they're all thinkin' I'm so
White and nerdy

Think I'm just too white and nerdy
Think I'm just too white and nerdy
Can't you see I'm white and nerdy
Look at me I'm white and nerdy
I wanna roll with the gangstas
But so far they all think I'm too
White and nerdy

Think I'm just too white and nerdy
Think I'm just too white and nerdy
I'm just too white and nerdy
Really, really white and nerdy

First in my class here at MIT
Got skills, I'm a champion at D&D
M.C. Escher, that's my favorite M.C.
Keep you're 40, I'll just have an Earl Grey tea
My rims never spin, to the contrary
You'll find that they're quite stationary
All of my action figures are cherry
Stephen Hawking's in my library

My MySpace page is all totally pimped out
Got people beggin' for my top eight spaces
Yo, I know pi to a thousand places
Ain't got no grills but I still wear braces
I order all of my sandwiches with mayonnaise
I'm a wiz at Minesweeper, I could play for days
Once you've see my sweet moves, you're gonna stay amazed
My fingers movin' so fast I'll set the place ablaze

There's no killer app I haven't run (run)
At Pascal, well I'm number one (one)
Do vector calculus just for fun
I ain't got a gat, but I got a soldering gun (what?)
Happy Days is my favorite theme song
I could sure kick your butt in a game of ping pong
I'll ace any trivia quiz you bring on
I'm fluent in JavaScript as well as Klingon

Here's the part I sing on...

You see me roll on my Segway
I know in my heart they think I'm
White and nerdy

Think I'm just too white and nerdy
Think I'm just too white and nerdy
Can't you see I'm white and nerdy
Look at me I'm white and nerdy

I'd like to roll with the gangstas
Although it's apparent I'm too
White and nerdy

Think I'm just too white and nerdy
Think I'm just too white and nerdy
I'm just too white and nerdy
How'd I get so white and nerdy

I been browsin', inspectin' X-Men comics
You know I collect 'em
The pens in my pocket, I must protect them
My ergonomic keyboard never leaves me bored
Shoppin' online for deals on some writable media
I edit Wikipedia
I memorized Holy Grail really well
I can recite it right now and have you R-O-T-F-L-O-L

I got a business doing websites (websites)
When my friends need some code, who do they call?
I do HTML for 'em all
Even made a homepage for my dog, yo
I got myself a fanny pack
They were havin' a sale down at The Gap
Spend my nights with a role of bubble wrap
Pop, pop - hope no one sees me gettin' freaky

I'm nerdy in the extreme
Whiter than sour cream
I was in AV club and glee club
And even the chess team
Only question I ever thought was hard
Was "Do I like Kirk or do I like Picard?"

Spend every weekend at the Renaissance Faire
Got my name on my underwear
They see me strollin', they're laughin'
And rollin' their eyes cause I'm so
White and nerdy

Just because I'm white and nerdy
Just because I'm white and nerdy
All because I'm white and nerdy
Holy cow, I'm white and nerdy

I wanna bowl with the gangstas
But oh well, it's obvious I'm
White and nerdy

Think I'm just too white and nerdy
Think I'm just too white and nerdy
I'm just too white and nerdy
Look at me I'm white and nerdy

Sunday, February 18, 2007

More on IQ and crime: In the earlier post, Tex wrote in the comments section that IQ-crime correlation is curvilinear: really smart people and the mentally retarded are the least criminal. Here's the percent ever arrested for each number out of ten answered correctly on the GSS vocab test (for whites only):

Percent ever arrested by vocabulary score

Ten 7.8
Nine 10.0
Eight 9.7
Seven 9.4
Six 10.3
Five 12.9
Four 12.8
Three 12.2
Zero-Two 11.4

We don't see much of drop in arrest among the dullest group (I imagine really slow people were not interviewed) but the smartest group is noticeable less likely to have ever been booked and fingerprinted. What happens if we estimate a logistic regression on the modal category--a score of 5--through the top group? This eliminates the curvilinearity problem (although it does restrict the range). The estimated coefficient is .085, with a p-value of .012. But IQ still explains less than 1% of the variation in arrest. Although it violates assumptions to use Pearson correlations, researchers do it all the time, so for people more familiar with that statistic, it is .04 in this analysis, and also .04 for the full range of IQ. I'm not impressed.

Saturday, February 17, 2007

Smart people are only slightly less criminal: Plato thought that if people broke the law, they did it out of lack of understanding, since men naturally and rationally pursue happiness, and crime only brings misery. He would have predicted a strong inverse correlation between IQ and criminality, but the General Social Survey disagrees with him. I used logistic regression to estimate the relationship between a person's score on a vocabulary test and whether they have ever been arrested (1 for yes, 2 for no). The coefficient for whites is .052, and it's .054 for blacks. In English, what that means is that IQ explains not even close to one percent of criminality. Maybe Plato wanted to see a virtue in people like himself that just isn't there.

Thursday, February 15, 2007

Looking again at southern intelligence: I was watching a 1993 video about juveniles and the death penalty and said to myself, "All these deathrow teens are dumb white Southerners," and it got me curious again about the idea that whites from that part of the country ain't so bright. When I looked at educational levels in an earlier post, the Southeast was low, but the West South Central Division (Arkansas, Oklahoma, Louisiana, Texas) was not. The General Social Survey (GSS) showed us previously that education and IQ are only moderately correlated, so let's look at the GSS's measure of intelligence--the number of vocabulary words out of 10 answered correctly. I list the divisional means from highest to lowest for whites only:

Mean vocabulary score

New England 6.65
Pacific 6.53
Middle Atlantic 6.52
Mountain 6.48
West North Central 6.33

USA 6.25

East North Central 6.14
South Atlantic 6.07
West South Central 6.00
East South Central 5.42

The stereotype is confirmed: the lowest three divisions are all southern. But the East North Central division (IL, IN, MI, OH, WI) is also below average. The Mountain states in someways feel like the South, but as we saw with data on Mormons, folks in that region are not dumb.

So what's the reason for low Southern averages, especially in Alabama, Mississippi, Tennessee, and Kentucky? A history of inbreeding? And folks from down there, don't get sensitive: we recognize that you have your Faulkners.

Sunday, February 11, 2007

Agnostics are the most intelligent: If you ask me to say the first thing that pops into my head when I am asked about who's the smartest in terms of believing in God, I would answer atheists. But it turns out that I'm wrong. According to the General Social Survey, agnostics are the smartest:

Mean vocabulary score


Doesn't believe 6.52
No way to find out 7.24
Some higher power 6.96
Believes sometimes 6.02
Believes but doubts 6.42
Knows God exists 6.05


Doesn't believe 4.60
No way to find out 4.36
Some higher power 5.65
Believes sometimes 4.47
Believes but doubts 4.98
Knows God exists 4.90

I'm focusing on the white numbers when I draw my conclusions since sample sizes are small for blacks. Atheists don't even come in second: "some higher power" does. Those who know God exists are by far the largest group, but the numbers here tell us that uncertainty (or vagueness, as in "some higher power") increases with IQ. (I, myself, don't believe on Tuesdays, Thursdays, and Saturdays).

Tuesday, December 05, 2006

Are smart people crazier? A reader asked if I would look to see if smarter people are more likely to be mentally ill. (Please, if you ever want me to see what the numbers say about anything, just ask). Using General Social Survey data, the mean vocabulary score for those ever having a mental problem is 7.25 (the range is from 1 to 10). For those reporting no problem, the average is 5.98: smarter people are definitely at risk. Surprisingly, the gap narrows for actually receiving help: the average of those who have sought counseling is 6.69; 6.18 for those who never have.

Myself, I must be smart as hell 'cuz I'm one crazy bastard.