Physics of the Future: How Science Will Shape Human Destiny and Our Daily Lives by the Year 2100

forgot that these images exist in his imagination only as general ideas.
    Furthermore, it is doubtful that you can read someone’s mind from a distance. All the methods studied so far (including EEG, fMRI, and electrodes on the brain itself) require close contact with the subject.
    Nonetheless, laws may eventually be passed to limit unauthorized mind reading. Also, devices may be created to protect our thoughts by jamming, blocking, or scrambling our electrical signals.
    True mind reading is still many decades away. But at the very least, an fMRI scanner might function as a primitive lie detector. Telling a lie causes more centers of the brain to light up than telling the truth. Telling a lie implies that you know the truth but are thinking of the lie and its myriad consequences, which requires much more energy than telling the truth. Hence, the fMRI brain scan should be able to detect this extra expenditure of energy. At present, the scientific community has some reservationsabout allowing fMRI lie detectors to be the last word, especially in court cases. The technology is still too new to provide a foolproof lie-detection method. Further research, say its promoters, will refine its accuracy. This technology is here to stay.
    Already, there are two commercial companies offering fMRI lie detectors, claiming a more than 90 percent success rate. A court in India already has used an fMRI to settle a case, and several cases involving fMRI are now in U.S. courts.
    Ordinary lie detectors do not measure lies; they measure only signs of tension, such as increased sweating (measured by analyzing the conductivity of the skin) and increased heart rate. Brain scans measure increased brain activity, but the correlation between this and lying has still to be proven conclusively for a court of law.
    It may take years of careful testing to explore the limits and accuracy of fMRI lie detection. In the meantime, the MacArthur Foundation recently gave a $10 million grant to the Law and Neuroscience Project to determine how neuroscience will affect the law.
    MY fMRI BRAIN SCAN
    I once had my own brain scanned by an fMRI machine. For a BBC/Discovery Channel documentary, I flew to Duke University, where they placed me on a stretcher, which was then inserted into a gigantic metal cylinder. When a huge, powerful magnet was turned on (20,000 times the earth’s magnetic field), the atoms in my brain were aligned to the magnetic field, like spinning tops whose axes point in one direction. Then a radio pulse was sent into my brain, which flipped some of the nuclei of my atoms upside down. When the nuclei eventually flipped back to normal, they emitted a tiny pulse, or “echo,” that could be detected by the fMRI machine. By analyzing these echoes, computers could process the signals, then reassemble a 3-D map of the interior of my brain.
    The whole process was totally painless and harmless. The radiation sent into my body was non-ionizing and could not cause damage to my cells by ripping apart atoms. Even suspended in a magnetic field thousands of times stronger than the earth’s, I could not detect the slightest change in my body.
    The purpose of my being in the fMRI scan was to determine preciselywhere in my brain certain thoughts were being manufactured. In particular, there is a tiny biological “clock” inside your brain, just between your eyes, behind your nose, where the brain calculates seconds and minutes. Damage to this delicate part of the brain causes a distorted sense of time.
    While inside the scanner, I was asked to measure the passage of seconds and minutes. Later, when the fMRI pictures were developed, I could clearly see that there was a bright spot just behind my nose as I was counting the seconds. I realized that I was witnessing the birth of an entirely new area of biology: tracking down the precise locations in the brain associated with certain thoughts, a form of mind reading.
    TRICORDERS AND PORTABLE BRAIN SCANS
    In the future, the MRI machine need not be the monstrous device found in hospitals today, weighing several tons and taking up an entire room. It might be as small as a cell phone, or even a penny.
    In 1993, Bernhard Blümich and his colleagues, when they were at the Max Planck Institute for Polymer Research in Mainz, Germany, hit upon a novel idea that could create tiny MRI machines. They built a new machine, called the MRI-MOUSE (mobile universal surface explorer), currently about one foot tall, that may