The new issue of Penn Medicine (Fall 2012) has a cover story on the work of David F. Dinges, PhD, with the National Aeronautics and Space Administration (NASA). The article’s hook is the recent completion of the Mars-500 experiment, a multinational effort to simulate a manned mission to Mars. Six volunteers spent 520 days in a specially designed isolation chamber, experiencing the conditions (except for microgravity) that the first human travelers to Mars will have to endure. They were under constant study by Russian, European, and Chinese scientists and spaceflight planners -- as well as one American research team, led by Dinges. The findings of the Dinges team have just been published in Proceedings of the National Academy of Sciences, an acknowledgment of their significance.
One can’t be associated very long with the University of Pennsylvania and its Perelman School of Medicine before learning about Dinges’s prominent role in sleep research. He is among Penn’s most widely known faculty members -- and his standing is amply recorded in the University’s publications. In fact, as a longtime Penn editor, I’ve found that Dinges -- chief of the Division of Sleep and Chronobiology and director of Unit for Experimental Psychiatry in the medical school’s Department of Psychiatry -- seems to crop up regularly in the publications I’ve worked for. As I settled into my job as the new assistant editor of The Pennsylvania Gazette back in 1985, I scanned its most recent issues. One (April 1985) included an article by my predecessor on Penn’s sleep research. Among the featured researchers was Dinges, then an assistant clinical professor of psychology in psychiatry and co-director of the Unit for Experimental Psychiatry. In the article, he pointed out that “our body needs rest from labor, but not sleep.” Instead, he said, “sleep seems to be something forced on us by the brain, for the brain.”
In 1992, when Marshall A. Ledger was editor, Penn Medicine ran “Call It Sleep,” which looked at, among other things, the work of Dinges on “the psychobiology of sleep and other biological rhythms.” As Dinges put it then, providing a handy summary: “My interest is in what happens to humans when their sleep is curtailed or shifted or out of phase with the environment -- such as in jet lag -- or their wakefulness is prolonged, the physiological and behavioral things that result, and what kinds of interventions or countermeasures can we find.”
Penn Health Magazine, which I edited for three years, dropped in on Dinges for his presentation during national “Brain Awareness Week,” in March 1998. Dinges, by that point chief of the Division of Sleep and Chronobiology, noted that “manipulating time has gotten our species into trouble.” One form of such trouble: the automobile accidents that occur when drivers fall asleep -- 142,000 such crashes each year. Sleep disorders, said Dinges, generally go unreported and cause significant loss of productivity, a reduction in the quality of life, deteriorating health, or even death. He encouraged sufferers to seek professional help, which had been expanding the available treatments.
In February 2006, Penn Medicine naturally included Dinges’s research in “Unquiet Slumbers,” by Martha Ledger. She described the highly sensitive psychomotor vigilance test that Dinges developed in 1985, which, among other things, demonstrated that an individual’s response to sleep deprivation is extremely consistent. In the article, Dinges pointed out that the same response “was trait-like -- which makes it look like it’s genetic,” a finding he called very exciting and provocative.
In the 1992 Penn Medicine article, Dinges noted that he is proudest of his work for NASA. Since that time, he received what is considered the highest honor NASA bestows upon non-governmental personnel whose accomplishments have contributed substantially to the agency’s mission -- the Distinguished Public Service Medal. Twenty years after his comments in Penn Medicine, it is that work that is featured in the most recent issue. As Mark Wolverton puts it in “Sleeping by Starlight,” “Dinges has been working with NASA for more than 20 years on one of the most challenging problems of space exploration: how to keep astronauts alert, active, and able to do their enormously complex and dangerous jobs in the most extreme conditions human beings will face.” One of the most intriguing comments Dinges makes in the current article is that the qualities traditionally considered “the right stuff” for astronauts might not be enough anymore: “We need to look at whether those are the right criteria for a 17-month mission to Mars or even longer. We probably need some different types of people” on the team of astronauts.
Still ahead this year in Penn Medicine: an article on the science of internal clocks and chronobiology, from fruit flies to humans. Which can only mean, in part . . . another visit with David Dinges!