title: Multisensory integration in the developing tectum is constrained by the balance of excitation and inhibition.
abstract: Multisensory integration (MSI) is the process that allows the brain to bind together spatiotemporally congruent inputs from different sensory modalities to produce single salient representations. While the phenomenology of MSI in vertebrate brains is well described, relatively little is known about cellular and synaptic mechanisms underlying this phenomenon. Here we use an isolated brain preparation to describe cellular mechanisms underlying development of MSI between visual and mechanosensory inputs in the optic tectum of Xenopus tadpoles. We find MSI is highly dependent on the temporal interval between crossmodal stimulus pairs. Over a key developmental period, the temporal window for MSI significantly narrows and is selectively tuned to specific interstimulus intervals. These changes in MSI correlate with developmental increases in evoked synaptic inhibition, and inhibitory blockade reverses observed developmental changes in MSI. We propose a model in which development of recurrent inhibition mediates development of temporal aspects of MSI in the tectum.
authors.affiliation: Department of Neuroscience, Brown University, Providence, United States.|Department of Cell and Molecular Biology, Tulane University, New Orleans, United States.
authors.forename: Daniel L
authors.initials: DL
authors.lastname: Felch
authors.affiliation: Department of Neuroscience, Brown University, Providence, United States.|Department of Biology, Bard College, New York, United States.
authors.forename: Arseny S
authors.identifier: 0000-0002-0429-1728
authors.initials: AS
authors.lastname: Khakhalin
authors.affiliation: Department of Neuroscience, Brown University, Providence, United States.
authors.forename: Carlos D
authors.identifier: 0000-0002-7378-7217
authors.initials: CD
authors.lastname: Aizenman
mesh_terms: D000818:Animals; D004558:Electric Stimulation; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005074:Evoked Potentials, Visual / Q000502:physiology*; D007814:Larva / Q000254:growth & development / Q000502:physiology; D040542:Mechanotransduction, Cellular / Q000502:physiology*; D009474:Neurons / Q000166:cytology / Q000502:physiology; D009924:Organ Culture Techniques; D018408:Patch-Clamp Techniques; D010775:Photic Stimulation; D013028:Space Perception / Q000502:physiology*; D013477:Superior Colliculi / Q000033:anatomy & histology / Q000254:growth & development / Q000502:physiology*; D013997:Time Factors; D014796:Visual Perception / Q000502:physiology*; D014982:Xenopus laevis / Q000254:growth & development / Q000502:physiology
keywords: inhibition; multisensory; neural circuit; neuroscience; tectum; visual development; visual system; xenopus