Complex temporal response patterns with a simple retinal circuit.
The retina can respond to a wide array of features in the visual input. It was recently reported that the retina can even recognize complicated temporal input patterns and signal violations in the patterns. When a sequence of flashes was presented, ganglion cells exhibited a variety of firing profiles and many cells showed an "omitted stimulus response" (OSR), in which they fired strongly if a flash in the sequence was omitted. We examined the synaptic origins of the OSR by recording excitatory synaptic currents from ganglion cells in the salamander retina in response to periodic flash sequences. Consistent with previous spike recordings, ganglion cells exhibited an OSR in their current response and the OSR shifted in time with a change in flash frequency such that it could predict when the next flash should have occurred. Although the behavior may seem sophisticated, we show that a simple linear-nonlinear model with a spike threshold can account for the OSR in on ganglion cells and that the variety of complex firing profiles seen in other ganglion cells can be explained by adding contributions from the off pathway. We discuss the physiological and simulation results and their implications for understanding retinal mechanisms of visual information processing.
Werner
Birgit
B
Program in Neuroscience, Boston University, Boston, MA, USA. birgit.werner@gmail.com
Cook
Paul B
PB
Passaglia
Christopher L
CL
D000818:Animals; D004307:Dose-Response Relationship, Radiation; D004558:Electric Stimulation / Q000379:methods; D005074:Evoked Potentials, Visual / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D018756:GABA Antagonists / Q000494:pharmacology; D018684:Glycine Agents / Q000494:pharmacology; D066298:In Vitro Techniques; D007814:Larva; D008959:Models, Neurological; D009415:Nerve Net / Q000502:physiology*; D009474:Neurons / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D010775:Photic Stimulation / Q000379:methods; D010852:Picrotoxin / Q000494:pharmacology; D011930:Reaction Time / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D012160:Retina / Q000166:cytology* / Q000502:physiology; D013331:Strychnine / Q000494:pharmacology; D013997:Time Factors; D014562:Caudata
D018756:GABA Antagonists; D018684:Glycine Agents; D010852:Picrotoxin; D013331:Strychnine