SOAR SPOTLIGHT: Natalie Herb '16
Olfactory Learning and Memory of Bang-Sensitive Drosophila melanogaster
Major: Biology, Ethics Minor
Hometown: New Tripoli, PA
Advisor: Christopher Jones
Briefly describe your project.
Bang-sensitive Drosophila melanogaster are fruit flies that have mutations which cause them to have seizures and exhibit paralysis when they are subjected to physical stimulation, which parallel those in humans that experience seizures. So, any information that is learned about these mutants can be relevant to people that have epilepsy and other seizure disorders. The goal of the project was to determine if there are any cognitive differences that these mutants exhibit compared to normal, wild-type flies. In order to test this, a classical conditioning approach was used. Flies were subjected to a negative stimulus, intense shaking, while being exposed to a certain odor. They were then exposed to a different odor while allowed to rest. After training the flies in this manner, they were allowed to choose between the odors in a device called a T-maze. Learning and memory ability was then determined by the fraction of flies that chose the odor that corresponded with rest, which they should have moved toward if they properly learned to associate this odor with having no punishment. By testing both wild-type and the bang-sensitive mutants in this manner, any differences in cognitive abilities could be seen.
Why did you decide to turn your idea into a SOAR project?
I thoroughly enjoyed Genetics and knew that I wanted to conduct research with Drosophila. I knew that Dr. Jones has been working with the bang-sensitive fruit flies and I had expressed an interest in working with these mutants. He proposed a few different types of projects that could be done, and ultimately I decided that I would like to pursue a study looking at the learning and memory of these mutants.
How did your faculty advisor guide you through your research?
The best part about working with Dr. Jones is his helpfulness and immense knowledge about genetics and Drosophila. Whenever I would come across an issue with experimentation, whether it was the procedure I was using, device for testing, or handling of the flies, Dr. Jones would have a suggestion to solve the problem. His insights were very beneficial in helping me to find the best procedure for testing the learning and memory of the flies.
What was your biggest obstacle?
The challenge that is present with the bang-sensitive flies is that whenever they are agitated, they can have a seizure. So, the punishment of shaking them often resulted in them having seizures. Due to the fact that the shaking causes seizures, I also tried to use a sugar reward rather than the negative stimulus, but trials with the wild-type flies were unsuccessful so this type of experiment was not used with the mutants. In addition, these mutants are very sluggish. This often resulted in very few flies moving to one side or the other when choosing an odor. With such few flies moving, this caused the performance index values that were calculated to be skewed.
What has been your biggest takeaway from this experience?
After completing this SOAR project, I have gained invaluable research experience. I have a better understanding of the process that is involved with conducting research and a better foundation for independent research in the future. In addition, I was glad that I was able to research a topic of interest outside the scope of the classroom and work on a project for an extended period of time.
What was the result of your project? Was it congruent with your hypothesis?
My hypothesis for this research was that the bang-sensitive fruit flies would have cognitive deficits compared to the wild-type files. The results of my project show that there are differences between the learning and memory of bang-sensitive Drosophila melanogaster versus wild-type. My data suggests that the bang-sensitive mutants had a diminished ability to learn and retain information since they had performance index values that were, on average, lower than the wild-type control.
Will you expand on your research after this summer is over? If so, where would you like to see it go?
I plan on continuing research with the bang-sensitive Drosophila throughout the year by doing an honors project. I will continue researching about their learning and memory, but likely with other techniques such as observing their courtship and aggressive behaviors.