Fig. 3: Individual differences in crowding and map size.

a Crowding distances for Observers 1 and 2. The crowding distance was measured radially at two eccentricities, 5° and 10°, in the four cardinal directions, twice at each location. The eight target locations are indicated by black dots. Crowding thresholds are displayed as horizontal and vertical lines. The endpoints of the lines indicate the neighboring letter locations at threshold spacing. Observer 2’s lines are slightly offset to avoid overlap. Dotted sectors represent the part of the visual field shown in (b). b For each observer, we show a portion of the visual field with letters spaced according to their Bouma factor. The portion of the visual field shown is 3° to 8.5° eccentricity and ±25° polar angle. The λ values count letters for the whole visual field up to 10° eccentricity, the extent of our psychophysics and retinotopy. c Retinotopic map boundaries (V1 to V4) from both hemispheres of the same two observers. Visual maps were independently drawn by two researchers (dashed and solid lines). Polar angle and eccentricity maps for the two observers are shown in Supplementary Fig. 1. Maps for all 49 participants are included as Supplementary Data 2. See makeFig3A.m and makeFig3B.m in GitHub repository.