Read Autopilot for Free Online Page B

When parts of a system form a complex network, what matters more than their actual microscopic structure is the relationship among the parts.
    In the brain, these nodes are made of anatomically distinct structures. The nodes are connected by edges which take the form of axons. Areas of the brain that are physically connected are called “structural networks.” Just as the body has different parts—the heart or lungs, for example—so too does the brain. These different brain parts are connected via alien-finger-like structures called fiber pathways. The brain’s structural network is dense with local clusters that are interconnected to each other and to the global network. You are likely familiar with well-known brain regions like the prefrontal cortex.
    We can think of nodes as airports, and we all know hub airports: Chicago, Heathrow, or Frankfurt. These airports are huge compared to regional airports and receive much more air traffic than smaller airports. Have you ever been able to fly direct from Portland, Oregon to Columbus, Ohio? Usually you would have to fly over Chicago (or maybe even to some out-of-the-way hub like Atlanta).
    The brain works the same way. There are certain structures in the brain that receive many more connections than other parts. These are the hubs. When you are idle your “brain hubs” light up with activity. More blood carrying oxygen and sugar flow to the hubs in your default mode network when you relax and start daydreaming.
    Over the last twenty years, technologies like the MRI and PET (Positron Emission Tomography) have allowed scientists to look inside the living brain and take snapshots of its activity or measure how much energy certain brain parts are consuming while subjects perform experiments. We now know that each anatomically distinct brain structure is specialized to do different things.
    Consider the heart. It is a specialized body part that circulates blood. Within the heart there are smaller parts and each performs a more specific function. For example, the left atrium pumps oxygenated blood to the aorta, which pumps it out to the rest of the body.
    Similarly, in the brain, the prefrontal cortex is involved in so-called “high-level” cognition like reasoning, short-term memory, controlling your emotions, planning activities, and bringing relevant memories to consciousness. Another brain region called the hippocampus (parts of which are active during rest) is responsible for creating long term memories and storing them in another part of your brain called the neocortex.
    The prefrontal cortex decides when it is relevant to recall certain memories or information stored in your neocortex. Each of these regions can again be subdivided into smaller sub-regions which, in concert, perform larger tasks like “remember the name of that woman who also has a child in my son’s daycare and who I see every day and who knows my name.”
    For example, let’s say you meet your Aunt Lisa. You have stored in your neocortex all kinds of information about your Aunt Lisa. This information is distributed throughout the cortex and has to be reassembled when you recall it. When you meet her, you remember that she has Basenjis, she lives in Milwaukee, and she is married to your Uncle Jim. Your prefrontal cortex helps bring all this information into your awareness because it’s suddenly relevant when you’re talking to your Aunt Lisa.
    Conversely, any new information that you get from Aunt Lisa, including the current episode during which you met her, goes from your awareness (which involves many parts of the brain) to your hippocampus. Then if you get a good night’s sleep, relax for a while, or even take a nap, the hippocampus more or less writes these new memories to your neocortex, which houses your long-term memories. This is called memory consolidation. It is especially important when you are learning new ideas or skills. So the best thing