Functional specialization of parallel motion detection circuits in the fly Journal Article

Author(s): Jösch, Maximilian; Weber, Franz; Eichner, Hubert; Borst, Alexander
Article Title: Functional specialization of parallel motion detection circuits in the fly
Abstract: In the fly Drosophila melanogaster, photoreceptor input to motion vision is split into two parallel pathways as represented by first-order interneurons L1 and L2 (Rister et al., 2007; Joesch et al., 2010). However, how these pathways are functionally specialized remains controversial. One study (Eichner et al., 2011) proposed that the L1-pathway evaluates only sequences of brightness increments (ON-ON), while the L2-pathway processes exclusively brightness decrements (OFF-OFF). Another study (Clark et al., 2011) proposed that each of the two pathways evaluates both ON-ON and OFF-OFF sequences. To decide between these alternatives, we recorded from motionsensitive neurons in flies in which the output from either L1 or L2 was genetically blocked. We found that blocking L1 abolishes ON-ON responses but leaves OFF-OFF responses intact. The opposite was true, when the output from L2 was blocked. We conclude that the L1 and L2 pathways are functionally specialized to detect ON-ON and OFF-OFF sequences, respectively.
Keywords: Electrophysiology; Drosophila melanogaster; photoreceptor
Journal Title: Journal of Neuroscience
Volume: 33
Issue 3
ISSN: 1529-2401
Publisher: Society for Neuroscience  
Date Published: 2013-01-16
Start Page: 902
End Page: 905
Sponsor: This work was supported by the Max-Planck-Society and the SFB 870 of the Deutsche Forschungsgemeinschaft.
DOI: 10.1523/JNEUROSCI.3374-12.2013
Open access: no