English
 
User Manual Privacy Policy Disclaimer Contact us
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
  Assessing the spatio-temporal dynamics of visual receptive fields by fMRI

Keliris, G., Shao, Y., Papanikolaou, A., Peng, X., Logothetis, N., & Smirnakis, S. (2010). Assessing the spatio-temporal dynamics of visual receptive fields by fMRI. Poster presented at 40th Annual Meeting of the Society for Neuroscience (Neuroscience 2010), San Diego, CA, USA.

Item is

Basic

show hide
Item Permalink: http://hdl.handle.net/11858/00-001M-0000-0013-BD74-5 Version Permalink: http://hdl.handle.net/21.11116/0000-0004-95CB-F
Genre: Poster

Files

show Files

Creators

show
hide
 Creators:
Keliris, GA1, 2, Author              
Shao, Y1, 2, Author              
Papanikolaou, A1, 2, Author              
Peng, X, Author
Logothetis, NK1, 2, Author              
Smirnakis, SM, Author              
Affiliations:
1Department Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, Max Planck Society, ou_1497798              
2Max Planck Institute for Biological Cybernetics, Max Planck Society, ou_1497794              

Content

show
hide
Free keywords: -
 Abstract: A fundamental problem of neuroscience is being able to understand the input-output relationship of early sensory areas. Central to this understanding is the notion of the receptive field (RF). Previous electrophysiological studies in the visual system of primates have demonstrated that receptive fields do not have fixed properties but are dynamically changing as a function of the stimulation conditions or behavioral tasks. In the human, aggregate (voxel-based) receptive field sizes (pRF) of early visual cortex were estimated by fMRI using standard retinotopic stimuli (Dumoulin SO, Wandell BA, Population receptive field estimates in human visual cortex, Neuroimage 39, 2008) but it would be desirable to obtain more detailed estimates of RF spatio-temporal properties. In this study, we have used flickering checkerboard stimuli (white noise) in order to measure the spatio-temporal response properties of population RFs by fMRI. Blood oxygen level dependent (BOLD) measurements were performed both in anesthetized macaques (4.7 Tesla vertical scanner) and awake-fixating human subjects (3 Tesla Siemens Trio). We found that the BOLD-signal amplitude in early visual cortex changes as a function of the checker-size of the stimulus and this can provide estimates of the central excitatory integration area as well as the surround suppression of the aggregate RFs. The estimates of the size of the central portion of the RFs were found to increase with eccentricity within each visual area as well as from lower to higher visual areas. The results were comparable to pRF-size estimates derived from additional experiments with classical retinotopic stimuli (expanding rings, rotating wedges, moving horizontal and vertical bars). Current work focuses on evaluating how RF parameter estimates change as a function of the temporal frequency and contrast of the stimuli. We believe that this method can provide robust estimates of RF parameters which can be used in longitudinal studies for the assessment of cortical reorganization and plasticity in patients suffering from retinal and cortical lesions.

Details

show
hide
Language(s):
 Dates: 2010-11
 Publication Status: Published in print
 Pages: -
 Publishing info: -
 Table of Contents: -
 Rev. Method: -
 Identifiers: BibTex Citekey: 7064
 Degree: -

Event

show
hide
Title: 40th Annual Meeting of the Society for Neuroscience (Neuroscience 2010)
Place of Event: San Diego, CA, USA
Start-/End Date: 2010-11-13 - 2010-11-17

Legal Case

show

Project information

show

Source 1

show
hide
Title: 40th Annual Meeting of the Society for Neuroscience (Neuroscience 2010)
Source Genre: Proceedings
 Creator(s):
Affiliations:
Publ. Info: -
Pages: - Volume / Issue: - Sequence Number: 371.6 Start / End Page: - Identifier: -