Sophisticated temporal pattern recognition in retinal ganglion cells.

TitleSophisticated temporal pattern recognition in retinal ganglion cells.
Publication TypeJournal Article
Year of Publication2008
AuthorsSchwartz, G, Berry, MJ
JournalJ Neurophysiol
Date Published2008 Apr
KeywordsAmbystoma, Animals, Evoked Potentials, Excitatory Amino Acid Antagonists, Excitatory Postsynaptic Potentials, GABA Antagonists, Glycine Agents, Larva, Pattern Recognition, Visual, Photic Stimulation, Picrotoxin, Retinal Ganglion Cells, Strychnine, Synaptic Transmission

<p>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.</p>

Alternate JournalJ Neurophysiol
PubMed ID18272878
PubMed Central IDPMC2856926
Grant ListR01 EY017934 / EY / NEI NIH HHS / United States
R01 EY017934-02 / EY / NEI NIH HHS / United States
R01 EY014196 / EY / NEI NIH HHS / United States
R01 EY017934-01A1 / EY / NEI NIH HHS / United States
R01 EY017934-03 / EY / NEI NIH HHS / United States
R01 EY-014196 / EY / NEI NIH HHS / United States