New faculty member studies decision-making in flies

by ZACH VEILLEUX

Understanding how fruit flies decide when to veer right and when to veer left is important work, not because it will help protect overripe bananas, but because it could lead to insights into how other organisms, including humans, make complex behavioral decisions.

Gaby Maimon, who has been appointed Rockefeller’s newest assistant professor and will open the Laboratory of Integrative Brain Function on January 1, has devoted his research program to figuring out how decisions, such as the decision about which way to navigate, are made in the tiny brains of Drosophila melanogaster flies. Using fluorescence microscopy and glass capillaries pulled to ultrafine tips, Dr. Maimon has developed a unique system that enables him to record the electrical activity of specific neurons in the fly brain as it flies. The setup allows him to understand what’s going on in the brain as the fly is exposed to — and reacts to — various stimuli.

His work falls somewhere between the traditional fields of behavioral neurophysiology and behavioral genetics. “In behavioral neurophysiology,” Dr. Maimon explains, “you record electrical activity from neurons as animals perform specific tasks; in behavioral genetics you manipulate the expression of genes and look for an impact on behavior. Both fields have developed great insights, but what has been difficult is to connect how genetic manipulations affect behavior through the real-time physiology of neurons. Our system may be useful for bridging this gap.”

Dr. Maimon, who was born in Israel, received his undergraduate degree from Cornell University and spent a year as a predoctoral research fellow in an NIH ethology lab before entering graduate school at Harvard University. He received his Ph.D. in 2005 and moved to the California Institute of Technology as a postdoc.

It was at Caltech, in the lab of Michael Dickinson, where he developed the method for obtaining “patch-clamp” recordings of the electrical activity of neurons in behaving flies. In his technique, which took over a year to develop, the experimenter tethers a fly to a stage in order to allow for the placement of electrodes, while still giving the animal the freedom to fly in place, to walk on a treadmill or to groom. Maimon and his colleagues coax the fly into locomotion — with a puff of air, for instance — and record the activity of specific neurons as the fly decides how to react to visual stimuli presented on a panoramic display surrounding the animal.

At Rockefeller, Dr. Maimon hopes to use his methodology, along with the techniques of genetic manipulation and molecular biology, to further our understanding of the neuronal basis of behavioral choice, the neuronal basis of behavioral timing and the origin of behavioral variability — why different individuals make different decisions and why the same individuals make different decisions at different times.

“It is a pleasure to welcome Gaby to Rockefeller,” says Paul Nurse, the university’s president. “Gaby is doing fascinating work to understand how neurons are linked to behavior, and he has developed a unique and very innovative system for studying decision-making in a model organism. His research has the potential to help us understand better how and why our brains lead us to make the decisions we make.”

“Better understanding the neural basis of behavior in a model organism such as the fly would be a great leap forward for understanding mammalian neurobiology as well,” says Dr. Maimon. “All animals have certain needs — such as deciding when and where to move. We hope that work in flies will give us a blueprint for what it would mean to answer the same types of questions in bigger organisms. Ultimately understanding how flies control the initiation and timing of action may teach us something about how the human brain controls precisely timed behaviors like speaking and what goes wrong in disorders such as Parkinson’s disease or Huntington’s disease.”