Neuromagnetic correlates of perceived contrast in primary visual cortex.

@article{Haynes2003NeuromagneticCO,
  title={Neuromagnetic correlates of perceived contrast in primary visual cortex.},
  author={John-Dylan Haynes and G{\'e}rard Roth and M. Stadler and Hans-Jochen Heinze},
  journal={Journal of neurophysiology},
  year={2003},
  volume={89 5},
  pages={
          2655-66
        }
}
When a target grating is flashed into a larger, surrounding grating, its contrast is perceived to be lower when both gratings are oriented collinearly rather than orthogonally. This effect can be used to dissociate the perceived contrast from the physical contrast of a target grating. We recorded the transient electric potentials and magnetic fields evoked by flashed target gratings and compared them with psychophysical judgments of perceived contrast. Both early (100 ms) and late (150 ms… 

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