"To understand the principles of human intelligence we need to reverse-engineer the human brain. Here, progress is far greater than most people realise. The spatial and temporal resolution of brain scanning is progressing at an exponential rate, roughly doubling each year. Scanning tools, such as a new system from the University of Pennsylvania, can now see individual interneuronal connections and watch them fire in real time. Already, we have mathematical models of a couple of dozen regions of the brain, including the cerebellum, which comprises more than half the neurons in the brain.

IBM is creating a highly detailed simulation of about 10,000 cortical neurons, including tens of millions of connections. The first version will simulate electrical activity and a future version will also simulate chemical activity. By the mid-2020s, it is conservative to conclude that we will have effective models of the whole brain."