Brain science's astounding pace of discovery is bringing new hope to many.
I want to take a rest from the political and religious wars and instead do a little of what I do with my students at the start of each semester. I'm teaching my course on the human brain this fall, and as usual my first lecture was called "While You Were Catching Rays-Discoveries Since the End of Last Semester."
This puts them (and me) on the frontier of brain science. I don't let them take notes, and I don't ask them about this stuff on the exams, but I do tell them that if they are not intrinsically interested in this material, they need to take a different course.
Here are a few highlights:
There are two pieces of good news on gene transfer. First, as reported in the June 12 Nature, researchers mainly at my own university (Emory) created a transgenic monkey with Huntington's disease, the degenerative brain disease that killed folk singer Woody Guthrie and many others. They introduced the defective gene into monkey eggs and the resulting monkeys-unfortunately for them but fortunately for us-developed the characteristic damage in their brains. This means that for the first time it will be possible to test new ways of preventing and treating the disease.
Second, two papers in the May 22 New England Journal of Medicine described parallel experiments in which normal genes were introduced into children to replace defective genes that gave them a rare form of congenital blindness. The idea is to try to slow down the loss of sight that they experience from birth. Human gene transfer has been done very little in recent years, because over-enthusiasm for it led to bad consequences, including a tragic death. The impact of the transferred normal genes on the children's vision was slight, but the method was shown to be safe, and this could be the beginning of very good news for future sufferers.
The journal Neuron on July 31 reported a new way to study post-partum depression in mice. Many women react to the changing hormones of pregnancy with sadness right after the birth, and some become severely depressed and even psychotic. Some even kill their babies. The UCLA scientists found that mice that seem depressed and neglect their pups have a genetic vulnerability in brain receptors for the neurotransmitter GABA. Next, they will begin testing women with post-partum depression to see if they have the same problem. If they do, new treatments may follow.
As reported in Nature on July 3, a group led by Marina Wolf made an important discovery about changes in another receptor, located in the brain's reward center, during the first three weeks after withdrawal from cocaine in addicted mice. This helps explain why craving in human addicts peaks right then. "My next job," Dr. Wolf said, "is to educate myself in drug discovery"–by which she means she's going to search for a cure for cocaine addiction.
Researchers at Cornell studied the laughter of congenitally deaf children while they were watching Naked Gun and Mr. Bean movie clips. Acoustically measured, their laughter is amazingly like that of hearing kids, even though they've never heard another person laugh. This shows that laughter patterns are wired into the brain-a human instinct?
Scientists at the Baylor College of Medicine, writing in the August 8 Science, reported a brilliant study comparing the brain activity of people with borderline personality disorder to normal people in a trust game. The borderline people, who in real life have terrible problems with relationships, were unable to get the idea that they have to earn the other player's trust in the game, and this was traceable to abnormal activity in the insula-a part of the cerebral cortex that monitors feelings and is involved in empathy.
Last but certainly not least, Science Online reported that an elderly lady with ALS-the devastating spinal disease that killed the great ballplayer Lou Gehrig-had some of her skin cells reprogrammed to make embryonic neuronal stem cells. This means they will be growing in culture and countless experimental manipulations will reveal things about this disease that almost no one ever dreamed of knowing. The details were published in the print issue this week–more about this in a later blog.