Fig. 3.

(A) Average t-statistical maps (5 subjects) displayed on their unfolded average cortical surfaces (t = 5.2 corresponds to p = 0.05 corrected for multiple comparisons). FMRI activation elicited by one image category is compared to both others. Oblique posterior-medial views are shown of the left and right hemispheres. These views reveal all differential activations. Black lines indicate the average borders of the visual field maps, thereby describing their probabilistic (P) location (Dumoulin et al., 2000, 2003). A star indicates the foveal representation. As can be seen from these t-statistical maps, early visual cortex (V1) respond strongest to full images, whereas later visual cortex (V3 and up) are activated more by the contour-only images. (B) Average BOLD signal amplitudes and standard deviations elicited by different image categories are plotted for the different visual areas. The visual field maps (V1–hV4) were identified in each subject. hMT+ was not identified in every subject and is therefore not included in the VOI analysis. The ventro-lateral occipital–temporal activations that were not covered by the identified visual field maps are grouped as region VO-. These results reveal two different response patterns that dissociate V1 from the rest of the visual cortex. V1 responds strongest to the full images, whereas later visual cortex is activated stronger by the contour images.