Brain's Wiring: More Like the Internet Than a Pyramid?
New research suggests that the distributed network of the Internet may be a better model for the human brain than a top-down hierarchy.
The brain has been mapped to the smallest fold for at least a century, but still no one knows how all the parts talk to each other.
A study in Proceedings of the National Academy of Sciences answers that question for a small area of the rat brain and in so doing takes a big step toward revealing the brain's wiring.
The network of brain connections was thought too complex to describe, but molecular biology and computing methods have improved to the point that the National Institutes of Health have announced a $30 million plan to map the human "connectome."
The study shows the power of a new method for tracing brain circuits.
USC College neuroscientists Richard H. Thompson and Larry W. Swanson used the method to trace circuits running through a "hedonic hot spot" related to food enjoyment.
The circuits showed up as patterns of circular loops, suggesting that at least in this part of the rat brain, the wiring diagram looks like a distributed network.
Neuroscientists are split between a traditional view that the brain is organized as a hierarchy, with most regions feeding into the "higher" centers of conscious thought, and a more recent model of the brain as a flat network similar to the Internet.
"We started in one place and looked at the connections. It led into a very complicated series of loops and circuits. It's not an organizational chart. There's no top and bottom to it," said Swanson, a member of the National Academy of Sciences and the Milo Don and Lucille Appleman Professor of Biological Sciences at USC College.
The circuit tracing method allows the study of incoming and outgoing signals from any two brain centers. It was invented and refined by Thompson over eight years. Thompson is a research assistant professor of biological sciences at the College.
Most other tracing studies at present focus only on one signal, in one direction, at one location.
"[We] can look at up to four links in a circuit, in the same animal at the same time. That was our technical innovation," Swanson said.
The Internet model would explain the brain's ability to overcome much local damage, Swanson said.
"You can knock out almost any single part of the Internet and the rest of it works."
Likewise, Swanson said, "There are usually alternate pathways through the nervous system. It's very hard to say that any one part is absolutely essential."
Swanson first argued for the distributed model of the brain in his acclaimed book Brain Architecture: Understanding the Basic Plan (Oxford University Press, 2003).
The PNAS study appears to support his view.
"There is an alternate model. It's not proven, but let's rethink the traditional way of regarding how the brain works," he said.
"The part of the brain you think with, the cortex, is very important, but it's certainly not the only part of the nervous system that determines our behavior."
The research described in the PNAS study was supported by the National Institute of Neurological Disorders and Stroke in the National Institutes of Health.
Map of the World Wide Web
Connect your Brain to the Internet?
Mind at Light Speed - A New Kind of Intelligence
Brain Machine Interfaces
Artificial brain "10 years away"
"We'll be able to upload our brains to a computer"
Blue Brain - Year One (Video)
The Global Brain (Video)
Neuroimaging Of Brain Shows Who Spoke To A Person And What Was Said
Magnetic field found to stimulate brain cells
An Input/Output Device for the Brain - Made of Light, Algae, and Bacteria
Latest News from our Front Page
Pro-Israel bias: BBC admits editorial breach in interview with Israeli defense chief
The BBC has reached a “provisional finding” to uphold complaints made by Palestinian activists that the broadcaster breached its editorial guidelines in a “soft” interview with the Israeli defense minister.
Complaints focused on BBC journalist Sarah Montague’s alleged failure to challenge controversial claims made by Israeli Defense Minister Moshe Ya’alon.
Journalist Amena Saleem, who works with the Palestine Solidarity Campaign (PSC), wrote ...
41% of Americans Support Criminalizing "Hate Speech"
The following are from a recent poll about what some are calling on for "hate speech"
1. Support for Hate Crimes Legislation
Do you support or oppose the federal law that requires increased penalties for hate crimes committed on the basis of the actual or perceived race, color, religion, national origin, ethnicity, or gender of any person?
2. Support for Expanding Hate Crimes
FBI Admits No Major Cases Cracked with Patriot Act Snooping Powers
FBI agents can’t point to any major terrorism cases they’ve cracked thanks to the key snooping powers in the Patriot Act, the Justice Department’s inspector general said in a report Thursday that could complicate efforts to keep key parts of the law operating.
Inspector General Michael E. Horowitz said that between 2004 and 2009, the FBI tripled its use of bulk ...
Sweetener Stevia Was Once Hailed As An Anti-Fertility Agent for Population Reduction
Maybe it's not so sweet now... If you've thought stevia, the natural alternative to sugar and artificial sweetners with aspartame, et al., is too good to be true, there may be a catch. Check out this textbook written in 1970 by Paul and Anne Ehrlich, the precursor to the textbook Ecoscience they wrote with Obama Science Czar John P. Holdren ...
TPP Aproved: Senate Republicans Give Obama New Powers - Details Remain 'Classified'
President Obama won a big victory for his trade agenda Friday with the Senate’s approval of fast-track legislation that could make it easier for him to complete a wide-ranging trade deal that would include 11 Pacific Rim nations.
A coalition of 48 Senate Republicans and 14 Democrats voted for Trade Promotion Authority late Friday, sending the legislation to a difficult fight ...
|More News » |