Posted on 03/18/2009 8:36:57 AM PDT by Pharmboy
UCLA researchers find that genes determine brain's processing speed
They say a picture tells a thousand stories, but can it also tell how smart you are? Actually, say UCLA researchers, it can.
In a study published in the Journal of Neuroscience Feb. 18, UCLA neurology professor Paul Thompson and colleagues used a new type of brain-imaging scanner to show that intelligence is strongly influenced by the quality of the brain's axons, or wiring that sends signals throughout the brain. The faster the signaling, the faster the brain processes information. And since the integrity of the brain's wiring is influenced by genes, the genes we inherit play a far greater role in intelligence than was previously thought.
Genes appear to influence intelligence by determining how well nerve axons are encased in myelin — the fatty sheath of "insulation" that coats our axons and allows for fast signaling bursts in our brains. The thicker the myelin, the faster the nerve impulses.
Thompson and his colleagues scanned the brains of 23 sets of identical twins and 23 sets of fraternal twins. Since identical twins share the same genes while fraternal twins share about half their genes, the researchers were able to compare each group to show that myelin integrity was determined genetically in many parts of the brain that are key for intelligence. These include the parietal lobes, which are responsible for spatial reasoning, visual processing and logic, and the corpus callosum, which pulls together information from both sides of the body.
The researchers used a faster version of a type of scanner called a HARDI (high-angular resolution diffusion imaging) — think of an MRI machine on steroids — that takes scans of the brain at a much higher resolution than a standard MRI. While an MRI scan shows the volume of different tissues in the brain by measuring the amount of water present, HARDI tracks how water diffuses through the brain's white matter — a way to measure the quality of its myelin.
"HARDI measures water diffusion," said Thompson, who is also a member of the UCLA Laboratory of Neuro-Imaging. "If the water diffuses rapidly in a specific direction, it tells us that the brain has very fast connections. If it diffuses more broadly, that's an indication of slower signaling, and lower intelligence."
"So it gives us a picture of one's mental speed," he said.
Because the myelination of brain circuits follows an inverted U-shaped trajectory, peaking in middle age and then slowly beginning to decline, Thompson believes identifying the genes that promote high-integrity myelin is critical to forestalling brain diseases like multiple sclerosis and autism, which have been linked to the breakdown of myelin.
"The whole point of this research," Thompson said, "is to give us insight into brain diseases."
He said his team has already narrowed down the number of gene candidates that may influence myelin growth.
And could this someday lead to a therapy that could make us smarter, enhancing our intelligence?
"It's a long way off but within the realm of the possible," Thompson said.
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Graphics from the study can be found at www.loni.ucla.edu/~thompson/HARDI/PDF/hardi3.jpg.
The UCLA Department of Neurology encompasses more than a dozen research, clinical and teaching programs. These programs cover brain mapping and neuroimaging, movement disorders, Alzheimer's disease, multiple sclerosis, neurogenetics, nerve and muscle disorders, epilepsy, neuro-oncology, neurotology, neuropsychology, headaches and migraines, neurorehabilitation, and neurovascular disorders. The department ranked No. 1 in 2005 and 2006 among its peers nationwide in National Institutes of Health funding.
Contact: mwheeler@mednet.ucla.edu 310-794-2265 University of California - Los Angeles
Ping.
Genes appear to influence intelligence by determining how well nerve axons are encased in myelin — the fatty sheath of “insulation” that coats our axons and allows for fast signaling bursts in our brains. The thicker the myelin, the faster the nerve impulses.
I thought Obama looked awfully thin.
Note they carefully used the term “inverted U-shape” rather than the politically incorrect term “bell curve”.
So basically hard headed individuals have hard water in their brain that won’t let the brain circuits do their jobs fast.</ sarcasm>
What is interesting about the United States is that we have a history of lower class immigrants coming here that have a hidden lineage of high intelligence. This superior intelligence could not blossom back in Europe or China or Asia due to the poverty, little access to education, religious discrimination. rigid class systems
But when these families immigrate here and their children are given a chance. And with our extensive university system their genius can blossom. Immigration can have a downside with all the illegals but there is also this unusually good side
The very smartest women I've known have relatively big heads with the heft of a cinder block. There's some correlation there.
Shh!
Don’t tell the lefties!
I thought Obama looked awfully thin.
0boma is the thin artistic type. Probably has long slender fingers for playing the piano. He is not the practical type. I'm positive Michelle managed the family's finances
0bomo is high IQ on the verbal side. On the scientific side he is a dunce, such as being a sucker for global warming and that embryonic stem cells getting the paralyzed up and walking
In college 0bomo would be an English major
We are ruled by English majors. By the verbally skilled manipulators -- lawyers
They are not scientifically oriented, far from it
“Note they carefully used the term “inverted U-shape” rather than the politically incorrect term “bell curve”.”
No, they didn’t:
“Because the myelination of brain circuits follows an inverted U-shaped trajectory, peaking in middle age and then slowly beginning to decline”
The inverted U-shaped trajectory describes the path over an individual’s lifetime. It applies to lots of things, such as annual earnings, average speed in running a marathon etc., not just intellectual performance. In contrast, a bell curve describes a group of individuals, with most people being average and relatively few falling into the extreme tails of ability.
IIRC, The Bell Curve demonstrated rather convincingly that the mean of the distribution of IQ’s among blacks was about 1 standard deviation lower than for whites. Thus, a randomly selected black person is more likely to be less intelligent than a randomly selected white person, but this doesn’t preclude there being black individuals (e.g., Thomas Sowell) whose intelligence greatly exceeds that of other white individuals (e.g., Ted Kennedy).
Are you dissing our first Teleprompter President?
American calories consumed and exercise during growth has something to do with it. I'm surprised how little study is done on how certain foods and exercises affect different kinds of growth. This is an important subject because once the growth stops the concrete is set for life.
A bell curve describes statistical distribution and is not limited to intelligence.
“Are you dissing our first Teleprompter President?”
To put it politely ... my CAT has more sense and style than this Communist imbecile. She is an intelligent Bengal and stands her ground plus she is beautiful!
well duh !
Definitely good American nutrition is a factor for these immigrant children. Look how many lower class poor Vietnamese children who became HS valedictorian in America.
In Vietnam the highest they could have gotten was rice farmer. Here he can get hired by Lehman or AIG and take home millions trading credit default swaps
Nice pick-up...
Great point...
The founders never understood “created equal” to apply in this sense.
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