Sophisticated temporal pattern recognition in retinal ganglion cells. Author Greg Schwartz, Michael Berry Publication Year 2008 Type Journal Article Abstract Pattern recognition is one of the most important tasks of the visual system, and uncovering the neural mechanisms underlying recognition phenomena has been a focus of researchers for decades. Surprisingly, at the earliest stages of vision, the retina is capable of highly sophisticated temporal pattern recognition. We stimulated the retina of tiger salamander (Ambystoma tigrinum) with periodic dark flash sequences and found that retinal ganglion cells had a wide variety of different responses to a periodic flash sequence with many firing when a flash was omitted. The timing of the omitted stimulus response (OSR) depended on the period, with individual cells tracking the stimulus period down to increments of 5 ms. When flashes occurred earlier than expected, cells updated their expectation of the next flash time by as much as 50 ms. When flashes occurred later than expected, cells fired an OSR and reset their temporal expectation to the average time interval between flashes. Using pharmacology to investigate the retinal circuitry involved, we found that inhibitory transmission from amacrine cells was not required, but on bipolar cells were required. The results suggest a mechanism in which the intrinsic resonance of on bipolars leads to the OSR in ganglion cells. We discuss the implications of retinal pattern recognition on the neural code of the retina and visual processing in general. Keywords Animals, Larva, Evoked Potentials, Synaptic Transmission, Photic Stimulation, Retinal Ganglion Cells, Ambystoma, GABA Antagonists, Excitatory Amino Acid Antagonists, Excitatory Postsynaptic Potentials, Glycine Agents, Pattern Recognition, Visual, Picrotoxin, Strychnine Journal J Neurophysiol Volume 99 Issue 4 Pages 1787-98 Date Published 2008 Apr ISSN Number 0022-3077 DOI 10.1152/jn.01025.2007 Alternate Journal J Neurophysiol PMCID PMC2856926 PMID 18272878 PubMedPubMed CentralGoogle ScholarBibTeXEndNote X3 XML