Friday, April 15, 2011

Reverse Engineering the Brain – from the Inside

Reverse engineering the brain, one of the 10 Grand Challenges posed by the National Academy of Engineering, and understanding the trillion interconnections of its circuitry won’t be easy, but there are some pretty interesting plans in the works, including a couple that, on the surface, sound very far-fetched.

To understand where today’s engineers stand, imagine engineers from the Middle Ages trying to unravel the mysteries of a twenty-first century computer. Like today’s engineers hoping to understand the human brain, they didn’t have the tools.

Technologies such as CT, MRI, fMRI, MEG and PET provide valuable data, but it’s the kind of information that only suggests what’s really going on in the brain’s circuitry. What engineers need is a tool that can examine the brain at a cellular level, without destroying it. One of the potential approaches that’s attracting attention is the use of nanobots -- billions of them -- that would travel in the blood stream throughout the body to the brain, where they would scan its structure and examine its circuitry as no current technology could. The bots, smaller than bloodcells, would transmit their data wirelessly to researchers for analysis and interpretation.

One challenge in this scenario is the blood-brain interface, a barrier that protects the brain from potentially harmful substances in the blood – bacteria, hormones and other toxins. Only oxygen and glucose can get though the barrier without causing damage. But there are some workarounds in discussion. One calls for nanobots to “reach across” the barrier with a robotic arm. In another scenario, nanobots break through the barrier, collect data, then return to the blood stream and repair the barrier as they exit.

The technology, as far-fetched as it seems, isn’t that far away. This means that in the not too distant future engineers will be analyzing the algorithms that transform tissue and mindless circuitry into human intelligence. That information, in turn, will accelerate the development of machine intelligence, leading to yet greater discoveries and a vast expansion of the human knowledge base. This process is already well underway -- computers are performing hundreds of tasks that used to be the sole province of human intelligence. 

As the National Academy of Engineering has said, the secrets about how living brains work "may be the best guide to engineering the artificial variety. Discovering those secrets by reverse-engineering the brain promises far more than building smarter computers. Advances gained from studying the brain may pay dividends for the brain itself. Understanding its methods will enable engineers to simulate its activities, leading to deeper insights about how and why the brain works and fails. Such simulations will offer more precise methods for testing potential biotechnology solutions to brain disorders, such as drugs or neural implants. Neurological disorders may someday be circumvented by technological innovations that allow wiring of new materials into our bodies to do the jobs of lost or damaged nerve cells. Implanted electronic devices could help victims of dementia to remember, blind people to see and crippled people to walk."

What do you think? Is it possible to reverse engineer the brain from the inside? And is it worth the effort? Tell us what you think.