This effort — if sufficiently financed — could develop new tools and techniques that would lead to a much deeper understanding of how the brain works. The ultimate aim, probably not reachable for decades, is to answer such fundamental questions as how the brain generates thoughts, dreams, memories, perception and consciousness — and to find ways to intervene and influence such brain activities. It may also be possible to determine how the brain changes over time in response to learning.

We are a long way from that kind of understanding today. Scientists using electrodes and existing imaging technologies have been able to study how individual neurons and small networks of neurons respond to stimuli. But the human brain has some 100 billion neurons, each interacting with perhaps 10,000 other neurons through complex circuitry that no existing technology has the speed or resolution to track. All told, there could be 1,000 trillion connections between neurons in the brain.