Gender differences and environmental inputs

In the comments section of my first post, commenter JB remarks

It is hard to fathom that well-to-do black women neglect to take doctor-recommended prenatal vitamins (which include magnesium). And that’s when vitamins are most important, no?

To which I reply:

I’d be willing to accept that genetic differences related to biochemical processing may also potentiate any environmental affects related to vitamin processing and blood-lead levels. Perhaps blacks simply have more difficulty utilizing vitamins and maintaining them in their bloodstream or removing toxins like lead for that matter?

My overall premise is that: Different groups may be more sensitive to certain environmental inputs than others.

While sex differences are more pronounced than racial differences, below I show a study on the effects of “social stressors” on pubertal and adult mice. Female mice exposed to pubertal or adult stress show significantly more sensitivity to amphetamines and nicotine, while males did not:

The present findings indicate that chronic social stressors alter HPA stress responses and locomotor responses to psychostimulants in females, and not in males, depending upon the age at which the animals underwent the social stressors procedure: Females stressed in adolescence showed enhanced behavioral sensitivity amphetamine, and females stressed in adulthood showed heightened corticosterone release in response to a new stressor.

[McCormick CM, Robarts D, Kopeikina K, et al. Long-lasting, sex- and age-specific effects of social stressors on corticosterone responses to restraint and on locomotor responses to psychostimulants in rats. Horm Behav. 2005;48:64-74.]

Human studies also show females are very negatively affected by stress in ways that males are not. This has societal implications as females will very soon outnumber males among medical school matriculates.

In contrast, prenatal exposure to nicotine appears to affect the blood pressure of male mice, but not female mice:

Prenatal nicotine had no effect on baseline BP but significantly increased Ang II–stimulated BP in male but not female offspring. The baroreflex sensitivity was significantly decreased in both male and female offspring. Prenatal nicotine significantly increased arterial media thickness in male but not female offspring. In male offspring, nicotine exposure significantly increased Ang II–induced contractions of aortas and mesenteric arteries. These responses were not affected by inhibition of endothelial NO synthase activity.

[Xiao D, Xu Z, Huang X, et al. Prenatal gender-related nicotine exposure increases blood pressure response to angiotensin II in adult offspring. Hypertension. 2008;51:1239-47.]

Carrillo’s way

In spite of receiving substantial media attention, there were very few surprises in the March 2^nd Texas primaries. A Muslim-American who doubts the official narrative about 9/11 lost in the Democratic gubernatorial primary to popular Houston mayor Bill White. Gov. Good Hair handily defeated his two opponents, Senator Kay Bailey Hutchinson and Debra Medina, another candidate who thinks the Jews did WTC. All-in-all it would appear the primaries were much ado about nothing.

One GOP incumbent in a notable race did lose on Election Day however, and he lost in a landslide.

Victor Carrillo, a geophysicist on the Texas Railroad Commission was handily defeated 61-39 by a small-town accountant by the name of David Porter. Carrillo who, outspent his opponent 12:1, had the backing of all mainstream party leaders, held superior qualifications and relevant experience, was somewhat bitter about his loss:

Early polling showed that the typical GOP primary voter has very little info about the position of Railroad Commissioner, what we do, or who my opponent or I were. Given the choice between “Porter” and “Carrillo” — unfortunately, the Hispanic-surname was a serious setback from which I could never recover although I did all in my power to overcome this built-in bias.

I saw it last time but was able to win because the “non-Carrillo” vote was spread among three Anglo GOP primary opponents instead of just one. Also, the political dynamics have changed some since 2004.

Unfortunately, Carrillo’s well-reasoned argument is sandwiched in between his whining about personal tragedies. While it’s hard to feel sorry for someone who will likely spend the rest of their days earning six-figures as an oil industry lobbyist, he may of a point. From LatinaLista:

Curious to see if other Latino GOP politicians suffered the same fate, a quick scan of the 2010 Republican Party Primary Election Night Returns reveals that in every race on election day where a Latino or Latino-sounding name and an Anglo were running against one another, the Anglo won.

In fact, the Anglo won by a landslide

Perhaps the time has come where Hispanic GOP politicians need to start adapting more “American” names. LatinaLista notes the dynamic appears to be different in 3 and 4 way races.

In the race for Texas’ 17^th Congressional district, Bill Flores (seen above) was able muster enough votes to get to a runoff election, yet he appears to face similar issues as Carrillo. While he had the backing of the NRCC and out-raised his closest opponent 3:1, he barely held a 4% edge over his soon to be runoff opponent 33:29. Apparently, a substantial portion of Waco voters seem to think he is an illegal.

It wasn’t all ray-sism that contributed to Carrillo loss. As noted about, the Teabagger impact on the election was not significant but still measurable. In statewide results it appears that as many as a third of voters were voting down-the-line against incumbents when they had opponents. Even Porter himself is a Teabagger:

Porter is running on an anti-Washington, D.C., anti-President Barack Obama platform of less regulation. According his Web site, Porter wants to use his position on the Railroad Commission of Texas as a “bully pulpit” to combat the “economic war [declared] by the current administration on the Texas oil and gas industry.”

Fantastic.

Texas has real problems ahead. Days like these you almost yearn for the MBA governor. (joke)

Completely unrelated to this post:

Liberals and Atheists Smarter? Intelligent People Have Values Novel in Human Evolutionary History, Study Finds

Arrogant Indians; Uppity Blacks

3^rd post in and I already need to invoke PlanetGrok’s law of HBD blogs. I went to a substantially African-American high school and I know of blacks all around the economic spectrum, so talking about blacks doesn’t really seem so absurd to be me. Yet, I realize a majority of blogs that focus on group differences (so-called HBD) have more malicious intents.  I do not. Still, this is a No-PC zone and while I realize a majority of blacks and Indians are decent people to be around (a majority of both groups are not ‘arrogant’), personal observations should still be talked about.

In a Steve Sailer comment thread I participated in, I noticed several other commenters remark on how ‘arrogant’ Indians in the West behave. PG has noted the narcissism of certain South Asian groups. Even Sasha Baron Cohen has a hilarious Indian-accented schtick based on this in the Madagascar movie series. A notable quote:

Excuse me, this is first class, its nothing personal, it’s just that we’re better than you

I had previously felt that my personal experience with Indian arrogance had been due to their understandable distain of me for my bad habit of dating their women. Now, I’m getting the feeling that this could be a characteristic of a measurable minority of Indians in the West. Many people do not notice this behavior from East Asians who often come across as humble, even if they feel differently in private.

As commenters in the Sailer thread noted: India is a craphole. While the 10 million or so ultra-selected Indians in 1^st world countries are relatively successful, a majority of the 1.5 billion South Asians in the world live mired in poverty comparable to that of the average African. Lynn gives India an average IQ of 81 (their tested score was 79) and the surrounding South Asian countries IQs of 80 or below. Long-existent Indian diaspora communities in the Caribbean and Southeast Pacific are hardly impressive.

So what is there for Indians to be arrogant about? Similar behavior has also been seen from some upper-class professional blacks; redneck southerners even have a term for it: uppity.

I think an HBD explanation exists for this behavior. According to Jason Richwine, the average Indian-American IQ is 112. This is more than two-standard deviations above their national mean. Similarly, it takes an IQ of 110 or so to pass calculus, something only a small percentage of blacks would be able to do. My theory: given that most racial groups spend their formative years around each other, successful blacks and Indians are well-aware of their intellectual superiority over their co-ethnics. This may lead them to assume they are also vastly mentally superior to members of other groups. Presently, differences in average intelligence exist between groups, whether or not they are heavily genetic remains to be seen.

It will be interesting to see the developmental trajectory of India though. International investors are under the impression that India is the next China. Many of them went to the orient 20 years ago and saw a desperately impoverished Chinese state. They expect similar progress from India, they may be disappointed.

Group differences in substance abuse and environments

It has been noted that certain groups are more prone to substance abuse than others. Why is this?

Inherent differences in IQ may be a contributing factor, as may environmental differences. A few studies on rats attempt to provide answers:

Rats with different behavioral histories, defined by rearing and housing in either an enriched condition (EC) or an isolation condition (IC), were trained in a two-lever operant procedure to discriminate 5.0 mg/kg cocaine from saline. In cocaine dose-generalization tests, the IC rats exhibited an ED₅₀ (1.01 mg/kg) significantly lower than the EC rats (ED₅₀:1.55 mg/kg). The cocaine-appropriate responding was emitted when the rats were treated with d-amphetamine, and for the d-amphetamine test doses the ED₅₀ (0.19 mg/kg) was again significantly lower for the IC rats compared to the ECs (ED₅₀:0.33 mg/kg). These data suggest that IC rats are more sensitive to the stimulus properties of indirect dopaminergic agonists than EC rats and highlight the importance of environmental variables in governing an organism’s response to the stimulus properties of abused drugs.

[Fowler, SC, Johnson, JS, Kallman MJ. In a drug discrimination procedure isolation-reared rats generalize to lower doses of cocaine and amphetamine than rats reared in an enriched environment. Psychopharmacology 1993;110:115-8.]

If only my parents had beat me, maybe the Adderall would last longer.

A Chinese study also drew the same conclusions with an opiate (EE-Enriched Environment; SE-Standard Environment):

We examined whether manipulations of the enriched environment affected behavioral response to morphine-induced reward in adulthood. Male mice were exposed to the EE, or SE condition for 2 months. When they reached adulthood, we examined their locomotor responses to an acute and repeated injection of morphine. The increase of locomotor activity observed in the EE mice was significantly less pronounced than that in the SE mice treated with morphine at 10 mg/kg. These animals then received six additional daily injections of morphine, and the ability of these treatments to produce behavioral sensitization was assessed by a challenge injection of morphine (10 mg/kg) following a 5-day drug-free interval. Mice exposed to the EE condition showed a significantly less robust behavioral response to the drug-induced reward than the SE mice did. We conclude that early EE condition affected the ability of morphine to induce behavioral sensitization. The rewarding and reinforcing effects of drugs were further studied in the place preference paradigm. The procedure has been found to be sensitive to the rewarding effects of drugs. We observed in experiments that morphine at the dose of 5 mg/kg induced place conditioning in mice. This dose has been previously shown to induce intense rewarding effects in conditioned place preference, which does not increase when using higher doses of morphine (Zachariou et al., 2001). Interestingly, the dose of morphine (5 mg/kg) that established robust place preferences in SE mice failed to establish place preferences in EE mice. Thus, the EE mice are less sensitive to the reinforcing effects of morphine and showed less prolonged morphine conditioning.

[Xu Z, Hou B, Gao Y, et al. Effects of enriched environment on morphine-induced reward in mice. Exp Neurol. 2007 ;204:714-9.]

How significant were these differences? Here’s how much time individual rats from the different environmental groups spent in the “morphine-conditioned” box:

**(p<0.01)

Environmental variables and group mean cognitive differences, part I

While obviously genetic differences exist between groups, they may not fully explain cognitive differences which are observed. Using recent research, I hope to illustrate some associated ‘environmental’ causes of cognitive differences between groups.

Learning and memory are fundamental brain functions affected by dietary and environmental factors. Here, we show that increasing brain magnesium using a newly developed magnesium compound (magnesium-L-threonate, MgT) leads to the enhancement of learning abilities, working memory, and short- and long-term memory in rats. The pattern completion ability was also improved in aged rats. MgT-treated rats had higher density of synaptophysin-/synaptobrevin-positive puncta in DG and CA1 subregions of hippocampus that were correlated with memory improvement. Functionally, magnesium increased the number of functional presynaptic release sites, while it reduced their release probability. The resultant synaptic reconfiguration enabled selective enhancement of synaptic transmission for burst inputs. Coupled with concurrent upregulation of NR2B-containing NMDA receptors and its downstream signaling, synaptic plasticity induced by correlated inputs was enhanced. Our findings suggest that an increase in brain magnesium enhances both short-term synaptic facilitation and long-term potentiation and improves learning and memory functions.

[Slutsky I, Abumaria N, Wu LJ, et al. Enhancement of learning and memory by elevating brain magnesium. Neuron. 2010; 65(2):165-77.]

I eagerly await easily available MgT supplements. Currently, the “Magnesium” you see in stores is actually Magnesium Oxide or some other crap that has difficulty crossing the blood-brain barrier.

How much Magnesium do different groups consume in their diet?

Despite the role of magnesium in maintaining health, much of the U.S. population has historically not consumed adequate amounts of magnesium. Furthermore, significant racial or ethnic disparities in magnesium intake exist. Our objective was to provide more recent data about magnesium intake in the U.S. population. We analyzed the 24-h dietary recall data from 4257 participants aged >or=20 y from the National Health and Nutrition Examination Survey 1999-2000. The median intake of magnesium was 326 mg/d (mean 352 mg/d) among Caucasian men, 237 mg/d (mean 278 mg/d) among African American men, 297 mg/d (330 mg/d) among Mexican American men, 237 mg/d (mean 256 mg/d) among Caucasian women, 177 mg/d (mean 202 mg/d) among African American women, and 221 mg/d (mean 242 mg/d) among Mexican American women. Among men and women, Caucasians had significantly higher mean intakes of dietary magnesium than African Americans but not Mexican Americans. Magnesium intake decreased with increasing age (P for linear trend = 0.035 for Caucasians; P for linear trend <0.001 for African Americans and Mexican Americans). Men had higher intakes of magnesium than women for each of the three race or ethnic groups (P < 0.001 in each group). Caucasian men, African American men and Caucasian women who used vitamin, mineral or dietary supplements consumed significantly more magnesium in their diets than did those who did not. Substantial numbers of U.S. adults fail to consume adequate magnesium in their diets. Furthermore, racial or ethnic differences in magnesium persist and may contribute to some health disparities.

[Ford ES, Mokdad AH. Dietary magnesium intake in a national sample of US adults. J Nutr. 2003; 133(9):2879-82.]

Environmental contaminates like Lead have been shown to be associated with poor cognitive performance. Do disparities in blood lead levels exist between races?

The geometric mean blood lead level declined 41% from 2.76 microg/dL (0.13 micromol/L) in 1988-1994 to 1.64 microg/dL (0.08 micromol/L) in 1999-2002. The percentage of adults with blood lead levels of 10 microg/dL (0.48 micromol/L) or higher declined from 3.3% in 1988-1994 to 0.7% in 1999-2002 (P<.001). In 1999-2002, the multivariable-adjusted odds ratio of having a blood lead level of 10 microg/dL (0.48 micromol/L) or higher was 2.91 (95% confidence interval [CI], 1.74-4.84) and 3.26 (1.83-5.81) for non-Hispanic blacks and Mexican Americans, respectively, compared with non-Hispanic whites. After multivariable adjustment, persons in the highest quartile (>or=2.47 microg/dL [>or=0.12 micromol/L]) compared with those in the lowest quartile (<1.06 microg/dL [<0.05 micromol/L]) of blood lead levels were 2.72 (95% CI, 1.47-5.04) and 1.92 (95% CI, 1.02-3.61) times more likely to have chronic kidney disease and peripheral arterial disease, respectively. In addition, higher blood lead levels were associated with a higher multivariable-adjusted odds ratio of hypertension among non-Hispanic blacks and Mexican Americans.

[Muntner P, Menke A, DeSalvo KB, et al. Continued decline in blood lead levels among adults in the United States: the National Health and Nutrition Examination Surveys. Arch Intern Med. 2005;165(18):2155-61]

What about pregnant women and blood lead levels?

Our results show that calories are positively related to lead level. Insofar as diet serves as amajor vehicle for the ingestion of lead in the United States, our finding is consistent withcalories’ being an indicator of dietary quantity. This finding also agrees with several otherstudies with multivariable analyses that take other nutrients into account (Hammad et al.1996; Lucas et al. 1996) although it does not agree with all (Mahaffey et al. 1986; Mootyet al. 1975).

[Lawrence M Schell, Melinda Denham, Alice D Stark, et al. Blood lead concentration, diet during pregnancy, and anthropometry predict neonatal blood lead in a socioeconomically disadvantaged population. Environ Health Perspect. 2003; 111(2): 195–200.]

How does fetal nutrition further affect offspring?

It is increasingly accepted that alterations of the intrauterine and early postnatal nutritional, metabolic, and hormonal environment may cause predispositions for the development of diseases in later life. Studies in the offspring of diabetic mothers have decisively contributed to this perception. Alterations of the fetal and neonatal environment which offspring of diabetic mothers ‘experience’ seem to program a disposition to develop obesity, diabetes mellitus and Syndrome X-like alterations throughout later life. Underweight at birth is also suggested to lead to an increased risk of Syndrome X in later life (‘Barker hypothesis’). Pathophysiological mechanisms are unclear. Hormones are important environment-dependent organizers of the developing neuro–endocrine–immune network, which finally regulates all fundamental processes of life. When present in non-physiological concentrations during ‘critical periods’ of perinatal life, induced by alterations in the intrauterine or neonatal environment, hormones can act as ‘endogenous functional teratogens’. Perinatal hyperinsulinism is pathognomonic in the offspring of diabetic mothers. Early hyperinsulinism also occurs as a result of early postnatal overfeeding. In rats, endogenous hyperinsulinism, as well as peripheral or only intrahypothalamic insulin treatment during perinatal development, may lead to ‘malprogramming’ of neuroendocrine systems regulating body weight, food intake and metabolism. This results in an increased disposition to become obese and to develop diabetes throughout life. In conclusion, a complex malprogramming of the central regulation of body weight and metabolism may provide a general etiopathogenetic concept, explaining perinatally acquired dispositions, thereby opening a wide field of primary prevention.

[Plagemann A. Perinatal programming and functional teratogenesis: Impact on body weight regulation and obesity. Physiol Behav. 2005;86(5):661-8.]

So-called “metabolic programming” may explain the high rate of obesity and coronary heart disease amongst blacks and Hispanics.

In addition to perinatal diet, maternal stress also plays a role in the state-of-mind of her offspring:

….However, considering that these newborns are brought up by mothers that are themselves stressed, it is more appropriate to define the stress as perinatal rather than simply prenatal, and to take into account postnatal maternal factors as well. It has been suggested that maternal glucocorticoids, one of the most important actors of the HPA axis, underlie the correlation between low birthweight and stress-related cardiovascular, metabolic and neuroendocrine disorders such as hypertension, type 2 diabetes, ischemic heart disease and different types of cognitive and behavioral disorders in adulthood

[Darnaudéry M, Maccari S. Epigenetic programming of the stress response in male and female rats by prenatal restraint stress. Brain Res Rev. 2008;57(2):571-85.]

So, looks like that whole pregnancy thing is kind of important. At least ethnic minorities in the United States take advantage of prenatal care – right?

In 2005, 78% of Hispanic pregnant women and 76% of black non-Hispanic (NH) women, compared with 89% of white NH women in the United States, began PNC in the first trimester

[Kuo TM, Gavin NI, Adams EK, et al. Racial disparities in Medicaid enrollment and prenatal care initiation among pregnant teens in Florida: comparisons between 1995 and 2001. Med Care. 2008;46(10):1079-85.]

Readers are encouraged to contribute.