Is there anything more everyday and familiar (given that we all possess one) and yet still so mysterious and puzzling as our own human brain? In about three pounds of tissue with the consistency of Jell-O, it packs 100 billion neurons, tens of trillions of neural connections and the low-watt processing power that has enabled our species to dominate this planet.

Yet even the often enigmatic workings of our mind are not immune to the probing of modern science. In recent decades imaging technol­ogies have revealed what areas of the brain are active when we are per­forming various mental tasks, for instance. Now researchers can also explain “What Makes Each Brain Unique”—even those of gene­tically identical twins. That is the subject of our cover story on the neuro­science of identity, authored by Fred H. Gage of the Salk Institute for Biological Studies in La Jolla, Calif., and Alysson R. Muotri of the University of California, San Diego. Genes and environment have long been known to influence human behavior. But as Gage and Muotri ex­plain, the signi­ficance of “jumping genes” is now becoming clear. These genes, which are especially active in the brain, copy and paste them­selves into new places in the genome, resulting in new traits.

When you are done, you might wrap your wetware around the mental sustenance offered in other features in the issue, such as “The Far, Far Future of Stars,” by astronomer Donald Goldsmith. He offers a reassuring view of our middle-aged cosmos, which is past its stellar-engine glory but still has trillions of years of vibrant activity to come. As Goldsmith eloquently puts it: “Our unfettered minds remain free to roam as far into the future as we choose.”

Entries Due
April 1 is the deadline for entries to the Google Science Fair—and all entries will automatically be considered for Scientific American’s $50,000 Science in Action award. The online competition is open to students around the globe in three age categories, ranging from 13 to 18.

Science in Action is a new addition to the Google Science Fair this year and will honor a project that tackles a social, environmental or health issue to make a practical difference in the lives of a group or community and that possibly can be scaled. Scientific American is also finding mentors to provide advice and thus further fos­ter the development of the Science in Action winner’s work for a year.

The Science in Action winner will be an­nounced in June and will join other Google Science Fair finalists at the company’s Mountain View, Calif., campus for a special awards event on Monday, July 23. I’ll be there and am looking forward to meeting these young scientists.