What Is Autism?
Dr. Fischbach joined the Simons Foundation in early 2006 to oversee the Simons Foundation Autism Research Initiative. Formerly Dean of the Faculties of Health Sciences at Columbia University, and former Director of the National Institute of Neurological Disorders and Stroke at the N.I.H. from 1998-2001, Dr. Fischbach received his M.D. degree in 1965 from Cornell University Medical School and interned at the University of Washington Hospital in Seattle.
He began his research career at the National Institutes of Health, serving from 1966–1973. He subsequently served on the faculty of Harvard Medical School, first as Associate Professor of Pharmacology from 1973–1978 and then as Professor until 1981. From 1981–1990, Dr. Fischbach was the Edison Professor of Neurobiology and Head of the Department of Anatomy and Neurobiology at Washington University School of Medicine.
In 1990, he returned to Harvard Medical School where he was the Nathan Marsh Pusey Professor of Neurobiology and Chairman of the Neurobiology Departments of Harvard Medical School and Massachusetts General Hospital until 1998.
What is Autism?
Wilczynski: Beginning with Dr. Fischbach, tell us as simply as possible what is autism?
Fischbach: Autism is a developmental disorder characterized by two main components: an inability to interact socially with other people with joint attention to understand other people’s thoughts. And the second component, the major component, is a real tendency to restricted interests, very narrowly focused interests and repetitive behaviors. That is just the core definition; autism reaches out in many different directions. It can be associated with language delays. It can be associated with epilepsy. It can be associated with some degree of intellectual disability, but the two core features of autism, I see, is impairments and social cognition, understanding and in restricted interests and repetitive behaviors.
Wilczynski: And how is it diagnosed?
Fischbach: Right now I think the gold standard is a clinical diagnosis, that an astute clinician interacting with a child, interviewing the parents, talking with teachers makes the diagnosis based on some standard tests and also on clinical impression and skill. There are no good tests yet, we’ll talk more about that later, that I know of for biochemical tests or imaging tests, although people are getting close and that is one of the real pushes that we’ll talk about and other objective tests. But right now the gold standard objective test is clinical judgment.
Wilczynski: Very good and I think that brings up the point that the clinicians really need to have broad experience at diagnosing individuals on the autism spectrum. Seeing one or two cases of autism or even a couple of cases of Asperger’s is often insufficient to prepare a psychologist, a developmental pediatrician or other health professional to really provide a comprehensive diagnosis. Tell me what in the brain seems to go awry to create autism spectrum disorders?
Fischbach: We just don’t know. Everyone on this panel I'm sure will have certain interests and biases and thoughts. I think my own bias is that there may be something wrong with the timing and the connectivity between regions rather than pointing to one particular spot in the brain. That it’s how these regions talk to each other and how they interact that is just not quite right.
Bookheimer: In particular I think that we’re getting closer to a model of autism that has to do with connectivity abnormalities in the brain and particularly early in development how connections are formed in the brain and, as Fischbach has pointed out, when they are formed in the brain. And in autism I think that one of the problems is that areas of the brain that are far from each other are not as well connected, whereas areas of the brain that are very close to each other seem to be over-connected. And so I think that it has to do with the developmental trajectory of when and where connections are formed that it appears to be awry.
Gerald Fischbach: The symptoms of autism are far better understood than its causes; psychiatrists classify the disorder as having two major components: impaired social cognition and a tendency toward narrow interests and repetitive behaviors.
It's just the current cycle that involves opiates, but methamphetamine, cocaine, and others have caused the trajectory of overdoses to head the same direction
- It appears that overdoses are increasing exponentially, no matter the drug itself
- If the study bears out, it means that even reducing opiates will not slow the trajectory.
- The causes of these trends remain obscure, but near the end of the write-up about the study, a hint might be apparent
Through computationally intensive computer simulations, researchers have discovered that "nuclear pasta," found in the crusts of neutron stars, is the strongest material in the universe.
- The strongest material in the universe may be the whimsically named "nuclear pasta."
- You can find this substance in the crust of neutron stars.
- This amazing material is super-dense, and is 10 billion times harder to break than steel.
Superman is known as the "Man of Steel" for his strength and indestructibility. But the discovery of a new material that's 10 billion times harder to break than steel begs the question—is it time for a new superhero known as "Nuclear Pasta"? That's the name of the substance that a team of researchers thinks is the strongest known material in the universe.
Unlike humans, when stars reach a certain age, they do not just wither and die, but they explode, collapsing into a mass of neurons. The resulting space entity, known as a neutron star, is incredibly dense. So much so that previous research showed that the surface of a such a star would feature amazingly strong material. The new research, which involved the largest-ever computer simulations of a neutron star's crust, proposes that "nuclear pasta," the material just under the surface, is actually stronger.
The competition between forces from protons and neutrons inside a neutron star create super-dense shapes that look like long cylinders or flat planes, referred to as "spaghetti" and "lasagna," respectively. That's also where we get the overall name of nuclear pasta.
Caplan & Horowitz/arXiv
Diagrams illustrating the different types of so-called nuclear pasta.
The researchers' computer simulations needed 2 million hours of processor time before completion, which would be, according to a press release from McGill University, "the equivalent of 250 years on a laptop with a single good GPU." Fortunately, the researchers had access to a supercomputer, although it still took a couple of years. The scientists' simulations consisted of stretching and deforming the nuclear pasta to see how it behaved and what it would take to break it.
While they were able to discover just how strong nuclear pasta seems to be, no one is holding their breath that we'll be sending out missions to mine this substance any time soon. Instead, the discovery has other significant applications.
One of the study's co-authors, Matthew Caplan, a postdoctoral research fellow at McGill University, said the neutron stars would be "a hundred trillion times denser than anything on earth." Understanding what's inside them would be valuable for astronomers because now only the outer layer of such starts can be observed.
"A lot of interesting physics is going on here under extreme conditions and so understanding the physical properties of a neutron star is a way for scientists to test their theories and models," Caplan added. "With this result, many problems need to be revisited. How large a mountain can you build on a neutron star before the crust breaks and it collapses? What will it look like? And most importantly, how can astronomers observe it?"
Another possibility worth studying is that, due to its instability, nuclear pasta might generate gravitational waves. It may be possible to observe them at some point here on Earth by utilizing very sensitive equipment.
The team of scientists also included A. S. Schneider from California Institute of Technology and C. J. Horowitz from Indiana University.
Check out the study "The elasticity of nuclear pasta," published in Physical Review Letters.
Scientists think constructing a miles-long wall along an ice shelf in Antarctica could help protect the world's largest glacier from melting.
- Rising ocean levels are a serious threat to coastal regions around the globe.
- Scientists have proposed large-scale geoengineering projects that would prevent ice shelves from melting.
- The most successful solution proposed would be a miles-long, incredibly tall underwater wall at the edge of the ice shelves.
The world's oceans will rise significantly over the next century if the massive ice shelves connected to Antarctica begin to fail as a result of global warming.
To prevent or hold off such a catastrophe, a team of scientists recently proposed a radical plan: build underwater walls that would either support the ice or protect it from warm waters.
In a paper published in The Cryosphere, Michael Wolovick and John Moore from Princeton and the Beijing Normal University, respectively, outlined several "targeted geoengineering" solutions that could help prevent the melting of western Antarctica's Florida-sized Thwaites Glacier, whose melting waters are projected to be the largest source of sea-level rise in the foreseeable future.
An "unthinkable" engineering project
"If [glacial geoengineering] works there then we would expect it to work on less challenging glaciers as well," the authors wrote in the study.
One approach involves using sand or gravel to build artificial mounds on the seafloor that would help support the glacier and hopefully allow it to regrow. In another strategy, an underwater wall would be built to prevent warm waters from eating away at the glacier's base.
The most effective design, according to the team's computer simulations, would be a miles-long and very tall wall, or "artificial sill," that serves as a "continuous barrier" across the length of the glacier, providing it both physical support and protection from warm waters. Although the study authors suggested this option is currently beyond any engineering feat humans have attempted, it was shown to be the most effective solution in preventing the glacier from collapsing.
Source: Wolovick et al.
An example of the proposed geoengineering project. By blocking off the warm water that would otherwise eat away at the glacier's base, further sea level rise might be preventable.
But other, more feasible options could also be effective. For example, building a smaller wall that blocks about 50% of warm water from reaching the glacier would have about a 70% chance of preventing a runaway collapse, while constructing a series of isolated, 1,000-foot-tall columns on the seafloor as supports had about a 30% chance of success.
Still, the authors note that the frigid waters of the Antarctica present unprecedently challenging conditions for such an ambitious geoengineering project. They were also sure to caution that their encouraging results shouldn't be seen as reasons to neglect other measures that would cut global emissions or otherwise combat climate change.
"There are dishonest elements of society that will try to use our research to argue against the necessity of emissions' reductions. Our research does not in any way support that interpretation," they wrote.
"The more carbon we emit, the less likely it becomes that the ice sheets will survive in the long term at anything close to their present volume."
A 2015 report from the National Academies of Sciences, Engineering, and Medicine illustrates the potentially devastating effects of ice-shelf melting in western Antarctica.
"As the oceans and atmosphere warm, melting of ice shelves in key areas around the edges of the Antarctic ice sheet could trigger a runaway collapse process known as Marine Ice Sheet Instability. If this were to occur, the collapse of the West Antarctic Ice Sheet (WAIS) could potentially contribute 2 to 4 meters (6.5 to 13 feet) of global sea level rise within just a few centuries."
SMARTER FASTER trademarks owned by The Big Think, Inc. All rights reserved.