* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Print this Page Presentation Abstract Program#/Poster#: 671.09/EE5
Central pattern generator wikipedia , lookup
Neurophilosophy wikipedia , lookup
Neural coding wikipedia , lookup
Metastability in the brain wikipedia , lookup
Neuroeconomics wikipedia , lookup
Development of the nervous system wikipedia , lookup
Neuropsychopharmacology wikipedia , lookup
Cognitive neuroscience wikipedia , lookup
Time perception wikipedia , lookup
Eyeblink conditioning wikipedia , lookup
Stimulus (physiology) wikipedia , lookup
Neuroinformatics wikipedia , lookup
Catastrophic interference wikipedia , lookup
Cortical cooling wikipedia , lookup
Synaptic gating wikipedia , lookup
C1 and P1 (neuroscience) wikipedia , lookup
Neuroesthetics wikipedia , lookup
Psychophysics wikipedia , lookup
Nervous system network models wikipedia , lookup
Types of artificial neural networks wikipedia , lookup
Convolutional neural network wikipedia , lookup
Neural correlates of consciousness wikipedia , lookup
9/19/12 Abstract Print View Print this Page Presentation Abstract Program#/Poster#: 671.09/EE5 Presentation Title: Effects of network symmetries on neural tuning properties. Location: Hall F-J Presentation time: Tuesday, Oct 16, 2012, 1:00 PM - 2:00 PM Authors: *R. J. VELTZ, T. SEJNOWSKI; CNL-S, CNL-S C/O The Salk Inst., La Jolla, CA Abstract: The goal of this study was to examine the effects of local connectivity on rate models of neural circuits in visual cortex. In its working regime, the network responded with similar responses over a broad range of parameters. It has been suggested that the local circuitry of the visual cortex operates at the edge of an instability where the network exhibits self-sustained stationary and oscillatory activity (Tsodyks et al., 1997; Ben-Yishai, 1995; Stimberg et al., 2009). In this regime, the inhibitory and excitatory connections are tightly balanced and dominate the thalamic input. Columns of these local circuits are also orderly in the primary visual cortex of cats and monkeys and are organized in a pinwheel structure. Although, the connections are locally homogeneous (Kenet et al., 2003; Marino-et al., 2005), the pinwheel structure and the thalamic input interact to produce a nonambiguous cortical representation of the stimulus. We studied the responses of orientation-tuned neurons to drifting gratings. In particular, we investigated the impact of the pinwheel structure on single cell responses. We assumed for simplicity that the pinwheels are organized in a square lattice, though similar results were obtained for other geometries. The parameters of the network were chosen to place the network close to a static instability, consistent with experimental measurements (Marino et al., 2005). In this state, depending on the spatial extent of the local connectivity and the f-I curve of the populations, the network displayed an intrinsic orientation preference at low contrast levels because of the pinwheel geometry. However, as the contrast increased above a contrast threshold, the cortical responses became more consistent with the stimulus orientation. This prediction can be tested with psychophysical stimuli across a range of contrasts near the perceptual threshold. Finally, when we included long-range connections with propagation delays, the www.abstractsonline.com/Plan/AbstractPrintView.aspx?mID=2964&sKey=2f105279-‐‑4b6d-‐‑4cef-‐‑b8bb-‐‑1… 1/2 9/19/12 Abstract Print View results were qualitatively similar. Disclosures: R.J. Veltz: None. T. Sejnowski: None. Keyword(s): ORIENTATION PINWHEEL CONTRAST Support: ERC grant 227747 - NERVI ONR N00014-12-1-0299 [Authors]. [Abstract Title]. Program No. XXX.XX. 2012 Neuroscience Meeting Planner. New Orleans, LA: Society for Neuroscience, 2012. Online. 2012 Copyright by the Society for Neuroscience all rights reserved. Permission to republish any abstract or part of any abstract in any form must be obtained in writing by SfN office prior to publication. www.abstractsonline.com/Plan/AbstractPrintView.aspx?mID=2964&sKey=2f105279-‐‑4b6d-‐‑4cef-‐‑b8bb-‐‑1… 2/2