Dr. Cy Borg is a microbiologist with superior sensory and intellectual capabilities. After a mishap in the laboratory in the year 2000, her sensory perception and original appendages were destroyed. But not for long. Science came to the rescue, replacing the scientist's traditional eyes with UV sensitive ones. Next, her two arms became four; her brain was enhanced with six nano-computers; and her body was shielded from further damage by smart armor. So, you can be sure this uber-intelligent scientist is ready for your borg-boggling question!

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Dear Nina,

Since 1848, when Phineas Gage had his famous accident, scientists have been fascinated by the case. As you know, an explosion during railroad construction blew a metal rod through Gage’s skull and brain. A few months after the accident, Gage felt ready to get back to work. However, his personality had changed dramatically. Gage had become impatient, stubborn, rude, and inconsiderate. He couldn’t make a plan and follow through on it. He could not do his old job. His friends said he was “no longer Gage.”

Scientists over the years have disagreed about which parts of Gage’s brain were damaged. We now think the ventromedial aspect of the frontal lobe was destroyed. One of the jobs of the ventral frontal lobe is to keep us from doing things that are inappropriate. When the ventral frontal lobe is damaged, people start doing the inappropriate things (like acting rudely toward others or swearing a lot) that are usually blocked. The frontal lobe is also very important for planning.

We can’t map emotions to parts of the cortex the way we can map sensory and motor functions. However, we do know that if scientists use electricity to stimulate specific parts of the brain in humans and animals, they can evoke specific emotions. We also know that if certain parts of the brain are destroyed, specific emotions can be flattened. For example, if nerves in the anterior cingulate cortex are cut, a person may find things that annoyed him in the past (fingernails on a chalkboard, mosquitoes, little brothers) to be less annoying. However, emotions don’t come just from the cortex. Other structures in the brain are involved, including the amygdala, hypothalamus, and brainstem. When scientists use electricity to stimulate the amygdala in humans, they evoke feelings of fear.

How does our brain work? In order to answer that question, I would need to fill this whole magazine, plus about ten textbooks. And that would be just the beginning. I think you are asking how our brain sends messages. The answer is that the brain is made up of about 100 billion cells called neurons. These cells are different from other cells in your body, because they are made specially for sending messages to one another really, really, really fast. One neuron can send a message to another by floating a special chemical across the tiny space in between the two cells. When you smell chocolate, cells in your nose send signals to your brain. Signals go almost instantly to different areas of the brain, causing you to realize you are smelling chocolate, to remember your grandmother’s chocolate chip cookies, and to think briefly about how much you miss your grandmother. Signals quickly go from your brain to your hand, telling your hand to grab the chocolate and put it in your mouth . . . or, even better, to put it in my mouth.

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