Word: positrons
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Dates: during 1990-1999
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...torn Niger, electron-positron colliders and astral planes helped some of Harvard's most talented thesis writers win Thomas Temple Hoopes Prizes this year...
When massive stars explode as supernovas, for example, they create a periodic table's worth of radioactive elements, some of which decay into antielectrons, known as positrons. A black hole, scientists believe, can also produce electron-positron pairs by superheating the material that spirals into its gravitational sinkhole. It was the radiation produced by annihilating positrons and electrons, not the antimatter itself, that was actually observed by Purcell at Northwestern and his collaborators at the Naval Research Laboratory in Washington...
Recently, positron-emission tomography (PET) scan studies at the UCLA School of Medicine have revealed that either Prozac or cognitive therapy can actually restore normal function in the obsessive-compulsive brain. The scans have documented that ocd patients have abnormal activity in the head of the caudate nucleus, a part of the brain's deep-dwelling basal ganglia, coupled with unusual activity in the orbital prefrontal cortex, just above the eye sockets. The caudate nucleus normally acts as a gatekeeper, determining which thoughts, feelings and behaviors take priority. When it malfunctions, the "worry inputs" generated in the orbital prefrontal region...
...third was the development of brain-scanning technologies, specifically PET (positron emission tomography), which can determine if patterns of neural activity in the brain are present during certain tasks. Using such technology, researchers have found that spatially organized parts of the brain are active in different places depending on the size of objects being viewed...
...experimentation. But science has finally begun to catch up with philosophy. Using sensitive electrodes inserted deep into the gray matter of test animals, researchers have watched vision as it percolates inward from the eye's retina to the inner brain. Powerful technologies such as magnetic resonance imaging (mri) and positron-emission tomography (PET) have also provided a window on the human brain, letting scientists watch a thought taking place, see the red glow of fear erupting from the structure known as the amygdala, or note the telltale firing of neurons as a long-buried memory is reconstructed. "What...