There is a huge difference between computers and the human brain. While the computer transmits information using electricity, the brain communicates its information using powerful chemicals. Let's say that you accidentally touch a hot pan on the stove. In less than two tenths of a second, millions of reactions take place while your brain performs a huge number of operations. As a result, you pull your hand away from the hot pan – very quickly!
Depending on the need, your brain uses many different chemicals for communication within itself and with the nerves that connect your brain to the rest of your body. Over 50 such chemicals have so far been identified. And it has been learned that many of these chemicals work in combination with each other so that over 800 different messages are possible.
Nor does the brain have set paths for messages, like a computer. In fact, it has been compared to a chemical soup rather than the circuits of a computer. In addition, the information paths in your brain change based on experience. If we can use computer language for a moment, the brain writes its own programs, doing many complicated tasks of which you and I are never aware.
We know that the computer is the product of careful design, but to argue that the much more complex human brain is an accident of nature makes very little sense!