Visual Orientation and Directional Selectivity through Thalamic Synchrony

• Type of Material: Article
• Authors: Garrett Stanley, Emory University; Jianzhong Jin, State University of New York; Yushi Wang, State University of New York; Gaëlle Desbordes, Georgia Institute of Technology; Qi Wang, Georgia Institute of Technology; Michael J. Black, Max Planck Institute for Intelligent Systems; Jose-Manuel Alonso, State University of New York
• Language: English
• Date: 2012-06-27
• Publisher: Lippincott, Williams & Wilkins
• Publication Version: Final Published Version
• Copyright Statement: © 2012 the authors.
• Final Published Version (URL): http://dx.doi.org/10.1523/JNEUROSCI.4968-11.2012
• Title of Journal or Parent Work: Journal of Neuroscience Nursing
• ISSN: 0888-0395
• Volume: 32
• Issue: 26
• Start Page: 9073
• End Page: 9088
• Grant/Funding Information: This work was supported by NSF Collaborative Research in Computational Neuroscience Grant IIS-0904630 (G.B.S., M.J.B., J.-M.A.), NSF Grant IIS-0534858 (M.J.B.), and NIH Grant EY005253 (J.-M.A.).
• Keywords: Neurosciences; STIMULUS SELECTIVITY; Life Sciences & Biomedicine; RECEPTIVE-FIELD PROPERTIES; Science & Technology; NEUROSCIENCES; NATURAL SCENES; LATERAL GENICULATE-NUCLEUS; COINCIDENCE DETECTION; SOMATOSENSORY CORTEX; CATS STRIATE CORTEX; SIMPLE CELLS; Neurosciences & Neurology; FEEDFORWARD INHIBITION; NEURONS IN-VIVO
• Research Categories: Engineering, Biomedical; Biology, General

Abstract

Thalamic neurons respond to visual scenes by generating synchronous spike trains on the timescale of 10-20 ms that are very effective at driving cortical targets. Here we demonstrate that this synchronous activity contains unexpectedly rich information about fundamental properties of visual stimuli. We report that the occurrence of synchronous firing of cat thalamic cells with highly overlapping receptive fields is strongly sensitive to the orientation and the direction of motion of the visual stimulus. We show that this stimulus selectivity is robust, remaining relatively unchanged under different contrasts and temporal frequencies (stimulus velocities). A computational analysis based on an integrate-and-fire model of the direct thalamic input to a layer 4 cortical cell reveals a strong correlation between the degree of thalamic synchrony and the nonlinear relationship between cortical membrane potential and the resultant firing rate. Together, these findings suggest a novel population code in the synchronous firing of neurons in the early visual pathway that could serve as the substrate for establishing cortical representations of the visual scene.