Discussion after the presentation.
Q: Isn't there a push-pull mechanism in the retina?
A: Yes I think there is. But it has to be recreated in the thalamus because the connections from retina to LGN are all excitatory.
Q: What is the proportion of cells?
A: Don't know.
Q: How do you select the response window?
A: Centered around the peak of the response.
Q: (About Laminar Distribution of Simple Receptive Fields). Will this hold in monkey as well?
A: No. I expect it to be different. The circuits that form the simple cells in monkeys are very different from than in cats.
Comment : Excitatory and inhibitory cells look differnt. Excitatory cells are spiny. Inhibitory are smooth.
Q: Orientation selectivity is coming from??
A: The pull can contribute to orientation selectivity.
Q: What do the complex cells look like?
A: They don't respond well to the "sparsely dynamic" stimulii. You need just the correct data set to come into a cell to make it fire.(?)
Q: Does anyone try to knock out LGN and try to record from V1?
Q: Do inhibitory cells make contact with other inhibitory cells?
A: Yes I believe they do. It seems that the orientation selective inhibitory cells have the same inhibition pattern as the excitatory cells.
Q: Did you look for evidence of syncrhony now that you have intra-cellular recording.
A: There are lot of blips
Q: What was the relative receptive field sizes of the complex interneurons and the simple excitatory neurons?
A: Roughly the same(?). We don't have an accurate measure.
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