RT Journal Article
SR Electronic
T1 Functional Specialization of Parallel Motion Detection Circuits in the Fly
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 902
OP 905
DO 10.1523/JNEUROSCI.3374-12.2013
VO 33
IS 3
A1 Joesch, Maximilian
A1 Weber, Franz
A1 Eichner, Hubert
A1 Borst, Alexander
YR 2013
UL http://www.jneurosci.org/content/33/3/902.abstract
AB 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 motion-sensitive 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.