June 2007
Volume 7, Issue 9
Vision Sciences Society Annual Meeting Abstract  |   June 2007
fMRI BOLD signal varies proportionally with the size of small saccades in human V1 and V2
Author Affiliations
  • Florian Baumgartner
    Experimental Psychology, University of Regensburg, Germany
  • Peter U. Tse
    Department of Psychology, Dartmouth College. NH, USA
  • Mark W. Greenlee
    Experimental Psychology, University of Regensburg, Germany
Journal of Vision June 2007, Vol.7, 736. doi:https://doi.org/10.1167/7.9.736
  • Views
  • Share
  • Tools
    • Alerts
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Florian Baumgartner, Peter U. Tse, Mark W. Greenlee; fMRI BOLD signal varies proportionally with the size of small saccades in human V1 and V2. Journal of Vision 2007;7(9):736. https://doi.org/10.1167/7.9.736.

      Download citation file:

      © ARVO (1962-2015); The Authors (2016-present)

  • Supplements

The goal of this research is to determine the neural correlates in early areas of visual cortex of small visually guided saccades executed during fMRI. Methods: We monitored voluntary saccades from one eye in the spatiotemporal domain of microsaccades using a Limbus infrared eyetracker (1 kHz sampling rate), while collecting fMRI data in a mixed event-related block design (3T Siemens Allegra scanner, TR = 402 ms, 7 slices along calcarine, TE = 30 ms, flip angle = 35°, 800 volumes, n = 6 subjects, 6–8 runs per subject). In blocks with small voluntary saccades (amplitudes: 0.16, 0.38, 0.82, 1.64, and 3.28 visual degrees; 12 pseudorandom events per epoch), subjects tracked with their gaze a small point that jumped either to the left or to the right. The fixation point was projected onto a one-degree wide horizontal white band superimposed onto a high-contrast, polar grating. In separate runs, retinotopic areas were mapped using the phase-encoding method (TR = 2000 ms, TE = 30 ms, FA = 90°, 30 slices, 152 volumes) in all subjects. Results: BOLD signals transiently increased in early visual areas during epochs with saccades of all sizes, relative to fixation epochs, including those that were as small as microsaccades. In V1 and elsewhere in visual cortex, the strength of the BOLD signal varied proportionally with the size of very small visually guided saccades. These results emphasize the need to monitor fixation behavior during fMRI and suggest that small saccadic and/or fixational eye movements can evoke significant responses in primary visual cortex.

Baumgartner, F. Tse, P. U. Greenlee, M. W. (2007). fMRI BOLD signal varies proportionally with the size of small saccades in human V1 and V2 [Abstract]. Journal of Vision, 7(9):736, 736a, http://journalofvision.org/7/9/736/, doi:10.1167/7.9.736. [CrossRef]
 Alexander von Humboldt Foundation, Bavarian Research Foundation

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.