A few random personal picks from the Society for Neuroscience’s annual meeting in New Orleans, which ended Oct. 17:
Inside Temple Grandin’s Head
Oliver Sacks, HBO and others have chronicled the life of autistic savant Temple Grandin. The unique patterns of thought produced by Grandin’s brain enabled her to design now-ubiquitous methods to treat cattle more humanely, and she has served as inspiration to others diagnosed with the condition. Until now, no one has tried to assess the actual brain physiology of the professor of animal sciences at Colorado State University.
Grandin herself wanted to know more about the biological basis of her cognitive strengths and deficits. So she entered into a collaboration with the University of Utah, which performed a battery of imaging tests—MRI, DTI and fMRI—to determine brain volume, cortical thickness and the structure of the insulating white matter that surrounds the long, wire-like axons that connect one brain cell with another. Supplemented with neuropsychological testing, researchers compared these results with those from three other “neurotypical” female subjects of about the same age.
It turns out that Grandin’s brain appears to be similar to that of other autistic savants. She has greater volume in the right hemisphere, which might account for her superior visuospatial abilities. She also has increased thickness of the entorhinal cortex, an area involved with memory As with others with autism, she has an overall larger brain size. And the enlarged amygdala and the smaller cortical thickness in the fusiform gyrus may relate to the deficits autistic individuals experience in dealing with emotion and reading faces. “There’s this idea in the savant literature that left hemisphere damage occurs during development and the right hemisphere compensates in some way,” says Jason Cooperrider, a graduate student at the University of Utah who presented the findings at the conference. “All of the savant skills are right hemisphere-dominant abilities, which would include Dr. Grandin’s exceptional visual and spatial ability which would be considered savant level.”
Grandin herself may have described what’s going on better than the data from the scanner. From her 2006 autobiography: “I think in pictures. Words are like a second language to me. I translate both spoken and written words into full-color movies, complete with sound, which run like a VCR tape in my head. When somebody speaks to me, his words are instantly translated into pictures.”
“I Just Got My Genes Done” Not.
Sniffer dogs are routinely recruited in the perilous extraction of buried landmines, demonstrating their prowess as exquisite biological sensors. Rats and honeybees as well have also shown an ability to detect mine location. Rats, for one, have their merits: they can scurry around a minefield without fusing ordnance and then make a clicking sound when they find something. A Belgian non-governmental organization APOPO has trained giant African pouched rats to smell landmine explosives, but it takes nine months of training to make the HeroRats, as they are called, into professional sappers.
Enter the geneticists. Charlotte D’Hulst of Hunter College presented work at the conference on mice with olfactory neurons genetically engineered to have 500 times more of the cell receptors that detect DNT, a compound almost identical to TNT. Imbuing the rodents with this capacity amounts, in essence, to a form of genetic learning. From the technical abstract: “This is the first time that [there has] been a mouse with a monoclonal nose, in which greater than 50 percent of the sensory neurons express a single odorant receptor gene.” The researchers are now trying to determine how well the mice actually perform.
Whether the transgenic “Superhero” mice, as they were dubbed in one headline, can live up to the performance of their painstakingly trained natural counterparts is a bit uncertain. Unaltered dogs and rats can detect, not only the explosive itself, but other materials—paint, plastic, rubber and cardboard—that compose the mine’s casing. Replicating that capability in a transgenic mouse—inserting a multitude of different cell receptor types—would probably be an overwhelming challenge.
All of this made me wonder whether the same approach could one day be adapted to humans. Could genetic learning substitute for those long years in the classroom? Is this a solution to the crisis of ever-rising costs of higher education? Nah, that’s not gonna happen. I can’t see when, if ever, you’ll be able to go home to a parent or spouse and say: “I Just Got My Genes Done.”
Scuba Diving Helps Long-Time Paraplegics
Cody Unser, the daughter of Indianapolis 500 winner Al Unser, Jr., never let herself be deterred by transverse myelitis, an immunological assault on the spinal cord that left her paralyzed from the chest down. Unser took up scuba and even started the Cody Unser Step First Foundation to help others with the disorder. She had always noticed that, after diving, that she felt increased sensation and better bladder control. With help from the foundation, she and two of her physicians—Adam Kaplin and Daniel Becker from Johns Hopkins—organized a small clinical trial to test whether scuba might help people with spinal-cord injuries.
Participants included: eight paraplegic veterans who made the dives, 10 able-bodied subjects who also dived, and two paraplegics who did not dive, but served as controls. After a series of dives in May of 2011 in the Cayman Islands, paralyzed subjects showed statistically significant improvement in response to light touch and pin pricks and experienced enhanced motor function. Kaplin, who presented the work (a poster entitled: “Healing Waters and Serotonin In The Restoration of Function In Chronic Spinal Cord Injury”), traced the improvement to a more than three-fold increase in serotonin that resulted from exposure to nitrogen during the multiple dives. The Johns Hopkins researchers now plan to work with V. Reggie Edgerton of UCLA to test whether nitrogen therapy (no dive needed) might be used in conjunction with Edgerton’s implantable electrical stimulators to help rehabilitate spinal-cord injury patients. “The take home moral of the story is listen to the patient and be willing to come along for the ride; “Cody brought people together and we came along and did the study,” Kaplin says. “Ultimately, it’s important to keep in mind that there’s existing circuitry. God bless them if they can get stem cells to rewire the nervous systems, but it looks like now it may be possible, not to rewire the nervous system, but to reactivate the existing wiring that’s there with methods like we demonstrated.”
Image Source: Steve Jurvetson/Wikimedia Commons