Negative BOLD fMRI Response in the Visual Cortex Carries Precise Stimulus-Specific Information
2007

Negative BOLD fMRI Response in the Visual Cortex Carries Precise Stimulus-Specific Information

Sample size: 7 publication Evidence: high

Author Information

Author(s): Bressler David, Spotswood Nicole, Whitney David

Primary Institution: University of California Davis

Hypothesis

Can negative BOLD responses in the visual cortex carry meaningful, stimulus-specific information?

Conclusion

The study demonstrates that negative BOLD responses in the visual cortex can provide precise information about object position.

Supporting Evidence

  • Negative BOLD responses can discriminate objects separated by less than 0.5 degrees.
  • Subjects were able to classify stimuli with increasing separation between Gabors.
  • Negative BOLD responses were found to be highly selective for object position.

Takeaway

Even when the brain shows a negative response to something we see, it can still tell us important details about that thing's position.

Methodology

The study used fMRI to measure BOLD responses while subjects viewed flickering Gabor stimuli at different positions.

Limitations

The physiological origin of the negative BOLD signal remains unclear.

Participant Demographics

Seven subjects participated in the study.

Statistical Information

P-Value

p<0.001

Statistical Significance

p<0.01

Digital Object Identifier (DOI)

10.1371/journal.pone.0000410

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