McCourt, M. E. (1982) A spatial frequency dependent grating-induction effect. Vision Research 22(1) 119-134.
McCourt's work involves grating induction (periodic apparent contrast induced in uniform fields by adjacent gratings). The gratings typically are very low spatial frequencies (.5 - 1 c/deg)
McCourt (1982) used a cancelation technique to measure the apparant contrast induced in a uniform field
- The induced contrast was up to 90% of the inducing grating contrast.
- Increasing the spatial frequency decreases the induced contrast.
- Increasing the width of the uniform field, as measured perpendicular to the grating, decreases the induced contrast.
- Square waves produce weaker induction than sine waves.
- Looks like a cortical affect because there is ocular transfer.
- The edge between the inducing grating and the induced grating does not contribute much to the induced contrast. In fact, blurring the edge elevates the inducted contrast.
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© 1995 Lance Hahn (email@example.com)