BETHANY, W.Va. - Do you have trouble going to sleep? Do you wakeup too early? Are you bothered by shift work or jet lag? Do you feel bad because you did not take your medications at the right time of day? Investigating such problems and others is the concern of the field of biological rhythms, or chronobiology.
This summer, Ashley Berardi, daughter of Fred and Regina Berardi of Follansbee, W.Va., is learning about these questions and others as she experiments with fruit flies in a research project at Bethany College.
The college sophomore is working in the Biology Department on two separate projects. One studies the effect of travel on the biological rhythms of fruit flies, and the other investigates human biological rhythms, specifically rhythms in spontaneous wrist movements.
Bethany College Professor John T. Burns believes that these research projects, funded by the West Virginia NASA Space Consortium, "provide an ideal opportunity for students to learn how to do science, rather than just learn about science from textbooks and lectures."
“Ashley excelled in the classroom, but it was really fun to see her tackle research problems in the lab and develop further as an independent thinker," said Dr. Burns.
"There is no substitute for coming up with your own ideas and hypotheses and then doing experiments to test them. Such undergraduate research experiences are increasingly expected by admission committees at graduate and professional schools.”
Berardi's first study focuses on Circadian rhythms, which are the approximately 24 hour biological rhythms, displayed by organisms on a daily basis. These rhythms tell our bodies when to sleep, when to awaken, when to eat, and when to reproduce. All of our physiology and behavior is dependent on these temporal patterns.
According to Berardi, "an unanswered question about the nature of circadian rhythms is whether the rhythms are ultimately a result of internal, biochemical processes (intrinsic) or the result of the timing information itself coming from outside geophysical forces (extrinsic)."
The controversial extrinsic hypothesis was championed by the late Dr. Frank A. Brown, Jr., a professor at Northwestern University. According to his extrinsic timing hypothesis, environmental geophysical cues, such as geomagnetic field fluctuations associated with sunrise and sunset may control our circadian rhythms.
Brown suggested that an east/west travel experiment could be designed to test his hypothesis. That is, if geomagnetic fields underlie circadian rhythms, then westward travel should lengthen circadian rhythms whereas eastward travel would shorten them.
Bethany College graduates Charles W. McCoy III '04, of Follansbee, W.Va.; Mike Dawley '02, of Vacaville, Calif. along with Berardi and Burns are testing Frank Brown’s hypothesis. Their travel experiments utilize computers and specialized monitors that keep track of the circadian rhythms of locomotion in fruit flies.
Burns explains, “Professor Brown had proposed this novel travel experiment to test his hypothesis, but only within the past few years has the combination of improved computer technology, the invention of fruit fly monitors, and the development of modern automobiles and improvements in our national transportation system allowed the experiment to be performed.”
The first travel experiment performed in 2002, by Burns and Dawley, transported fruit flies by van from Bethany to Sacramento, Calif. and back. Several additional experiments have followed, and McCoy has been involved in all of these later travel experiments.
Fruit flies are small and easy to transport in the monitors. While traveling, the flies live inside small glass tubes with some agar-based food. Scientists already know that fruit flies and humans share many of the same details in their biochemical physiology when it comes to circadian rhythms.
The monitors detect the movements of the flies by breaks in an infrared light beam that passes through the glass tubes that house the flies. Each time the fly moves across the middle of the tube, it breaks the beam of light. A photocell responds to these disturbances, and the number of breaks is tallied and stored for each minute, and the information is later downloaded onto a computer.
Berardi summarizes, “By traveling across the country with fruit flies, we can either prove or disprove Brown's hypothesis. It is known that the sun sets later in the West and earlier in the East. By traveling westward with the fruit flies, we should see a lengthening in their rhythms because the sunset and many associated geophysical field changes are occurring later."
"The opposite is true traveling eastward; a shortening of the rhythms should be observed. If the rhythms do, indeed, lengthen and shorten accordingly, then we have proven Frank A. Brown correct. If there is no considerable change in the rhythms, then we have proven the rhythms to be intrinsic, or controlled by internal mechanisms.”
With successive trips and much analyzing of data by Berardi and several others, including Danielle Buck '06 (Bethel Park, Pa.), results have shown that rhythms do lengthen going westward, but there is less evidence of shortening coming back eastward.
Because the flies tend to die after several days of travel, less data is available for the eastward leg of the round trip.
During the past months, Berardi has been crunching the numbers obtained from the activity monitors that record the fruit flies’ activity. With the help of computer software, she has learned to take the data from the fruit fly monitors, download them to a PC, and then calculate the data to see if the rhythms lengthened or shortened during the trips.
Ashley commented, “Working with this specialized software has allowed me to become more familiar not only with circadian rhythms but also time series analysis and the advanced statistical methods used in a major research project.”
The same numerical techniques are also used by many other scientists interested in time series analysis such as climatologists, economists, and engineers.
Berardi’s second research effort, the study of human circadian rhythms, is done with the use of Actiwatches. Actiwatches record on a computer chip whenever they are moved. By strapping these “watches” onto the wrists of volunteers, the wrist movements can be measured daily, and circadian rhythms are evident in the record.
Erica Smith '06 (Sistersville, W.Va.) used Actiwatches in her senior project. She studied the sub-cycles present in circadian rhythms in family members contrasted with non-related individuals.
Smith used two pairs of identical twins, one pair of fraternal twins, and one pair of non-related individuals for her subjects. Results of Smith’s study proved that circadian rhythms are not significantly influenced by genetics; however, factors such as individuals being roommates or sharing common activity schedules may cause some synchronization of the circadian rhythms among individuals.
Corrine Costellic '04 (Erie, Pa.) also completed a study with Actiwatches as her senior project. She studied the differences in circadian rhythms between two families to see if there were any relationships between rhythms in the families. With the evaluation of data, results showed that there is no genetic relationship found in circadian rhythms within families; however, age and gender may play some minor role in an individual’s rhythm.
Berardi plans to research that fact this year. The project includes using the Actiwatches to measure the activity of a diverse group of people. With the results, she will determine if circadian rhythms can be used to identify people according to their gender. Also, possible effects of a women’s menstrual cycle on her circadian rhythm will be noted.
With these ongoing projects on chronobiology being conducted, students have the opportunity to work closely with the Bethany professors as they gain valuable research experience.