The American computer company IBM says it has developed a microprocessor – a computer chip – that works much like the human brain. IBM calls the chip True North. It is the \_36\_ of a postage stamp. The chip has 5.4 billion tiny parts that work like the human brain's neurons and synapses. Neurons and synapses are the cells and electric forces that carry messages \_37\_ the brain. True North has 1 million neurons and 256 million synapses. The human brain has 100 billion neurons and up to 150 trillion synapses. IBM says it can program the new chip to understand difficult problems and then solve them as humans would. The company says the True North chip could be used as a brain for \_38\_ robots. It can also be used for controlling new kinds of wheel chairs or for recording conversations \_39\_ several people and then making a printed record of those conversations. True North is still being tested. But IBM says it could be available for public use in two to three years. The chip is just one example of machines becoming more and more like humans. This field of study is called artificial intelligence, or AI. Some experts believe computers will someday become more intelligent than humans.