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dc.contributor.advisorH. Sebastian Seung.en_US
dc.contributor.authorGreene, Matthew (Matthew Jason)en_US
dc.contributor.otherMassachusetts Institute of Technology. Department of Brain and Cognitive Sciences.en_US
dc.date.accessioned2017-01-12T18:33:15Z
dc.date.available2017-01-12T18:33:15Z
dc.date.copyright2014en_US
dc.date.issued2016en_US
dc.identifier.urihttp://hdl.handle.net/1721.1/106432
dc.descriptionThesis: Ph. D., Massachusetts Institute of Technology, Department of Brain and Cognitive Sciences, June 2016.en_US
dc.descriptionCataloged from PDF version of thesis.en_US
dc.descriptionIncludes bibliographical references (pages 51-56).en_US
dc.description.abstractThis thesis addresses the question of how direction selectivity (DS) arises in the mouse retina. DS has long been observed in retinal ganglion cells, and more recently confirmed in the starburst amacrine cell. Upstream retinal bipolar cells, however, have been shown to lac, indicating that the mechanism that gives rise to DS lies in the inner plexiform layer, where the axons of bipolar cells costratify with amacrine and ganglion cells. We reconstructed a region of the IPL and identified cell types within it, and have discovered a mechanism which may explain the origin of DS activity in the mammalian retina, which relies on what we call "space-time wiring specificity." It has been suggested that a DS signal can arise from non-DS excitatory inputs if at least one among spatially segregated inputs transmits its signal with some delay, which we extend to consider also a difference in the degree to which the signal is sustained. Previously, it has been supposed that this delay occurs within the starburst amacrine cells' dendrites. We hypothesized an alternative, presynaptic mechanism. We observed that different bipolar cell types, which are believed to express different degrees of sustained activity, contact different regions of the starburst amacrine cell dendrite, giving rise to a space-time wiring specifity that should produce a DS signal. We additionally provide a model that predicts the strength of DS as a function of the spatial segregation of inputs and the temporal delay.en_US
dc.description.statementofresponsibilityby Matthew Greene.en_US
dc.format.extent56 pagesen_US
dc.language.isoengen_US
dc.publisherMassachusetts Institute of Technologyen_US
dc.rightsM.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.en_US
dc.rights.urihttp://dspace.mit.edu/handle/1721.1/7582en_US
dc.subjectBrain and Cognitive Sciences.en_US
dc.titleA connectomic analysis of the directional selectivity circuit in the mouse retinaen_US
dc.typeThesisen_US
dc.description.degreePh. D.en_US
dc.contributor.departmentMassachusetts Institute of Technology. Department of Brain and Cognitive Sciences.en_US
dc.identifier.oclc967336369en_US


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