"Processing properties of ON and OFF pathways for Drosophila motion detection" by Dr Rudy Behnia

Past Event

05 January 2015, 1:00pm - 2:30pm

Lecture Theatre, Oxford Martin School
34 Broad Street (corner of Holywell and Catte Streets), Oxford, OX1 3BD

This seminar is run by the Programme on Mind and Machine, an Oxford Martin School programme on The Centre for Neural Circuts and Behaviour

Speaker: Dr Rudy Behnia, Department of Biology and Center for Neural Science, New York University

Abstract: Flies possess two parallel motion channels specialised for detecting moving light or dark edges. Each of these pathways requires two critical processing steps: differential delay between the spatial input channels in each pathway, and asymmetric treatment of light and dark contrast signals. While the neural substrates that define the input and output channels of the ON and OFF circuits have been identified, the neural implementions of these two critical processing steps remain elusive. Using in vivo patch-clamp recordings, I show that four medulla interneurons exhibit these processing properties. The interneurons Mi1 and Tm3 respond selectively to brightness increments, with the response of Mi1 delayed relative to Tm3. Conversely, Tm1 and Tm2 respond selectively to brightness decrements, with the response of Tm1 delayed compared to Tm2. Hassenstein-Reichardt correlator models that are constrained by these measurements produce outputs consistent with previously measured tuning properties of motion detectors in flies.

All welcome, For further information please contact Fiona Woods at fiona.woods@cncb.ox.ac.uk

About the speaker

Rudy Behnia received a Ph.D. at the MRC Laboratory of Molecular Biology in Cambridge, where she worked on Golgi membrane trafficking with Sean Munro. She is currently an EMBO and HFSP Long-Term Postdoctoral Fellow in the laboratory of Claude Desplan.