Fly perception of a visual motion illusion (Reiser Lab, Janelia Farm)
I was briefly obsessed with figuring out how flies perceive a visual illusion called reverse-phi motion. Unlike a standard motion pattern, the contrast of a reverse-phi motion pattern reverses as it moves. This causes us (and flies), to perceive motion moving in the opposite direction. Illusions like reverse-phi can be used to investigate the algorithms and neural computations that underlie motion detection. The fact that many animals see reverse-phi (e.g., humans, fish, flies) suggests that it is an important and fundamental consequence of motion detection.
We used a virtual reality flight simulator to examine how flies respond to patterns of reverse-phi motion, and 2-photon calcium imaging to study how reverse-phi motion is encoded within motion-sensitive in the fly brain. For more info about electrophysiology in behaving flies, check out FlyFizz, and for info about our visual display system, go to flypanels.org.
Sensitivity to the polarization of light in crayfish (Johnsen Lab, Duke)
In addition to wavelength and intensity, light has a third fundamental property that is defined by the distribution of the planes of vibration of the electrical fields within the wave. Many animals have specific structures that analyze the polarization of light for tasks such as orientation, navigation, and object detection. The crayfish, in particular possesses all the anatomical and neural structures required to detect the polarization properties of light. For my undergraduate thesis I designed a behavioral experiment to test whether polarization cues in an otherwise transparent moving stimulus increase the ability of the crayfish to detect the object.
The Neural Basis of Polarization Sensitivity in Crabs (Tomsic Lab, UBA)
I spent the summer of 2007 working in the Laboratorio de Neurobiología de la Memoria at the University of Buenos Aires, studying the behavioral and neural mechanisms of polarization sensitivity in the crab, Chasmagnathus granulatus. I recorded from polarization sensitive neurons in higher visual centers, and quantified neural responses to static and moving polarized stimuli.
Conspecific Pollen Preference in the Monkeyflower, Mimulus (Fishman Lab, U-Montana)
While living in Montana in the spring of 2007, I worked part-time as a technician in Lila Fishman's Lab. We studied gametophytic evolution by analyzing patterns of transmission ratio distortion in F2 and backcross hybrids of two closely related monkeyflower species. We found several genomic regions that completely accounted for the precedence of Mimulus guttatus pollen over Mimulus nasutus pollen in mixed pollinations of M. guttatus.
