LSO-IC projection differences in WT and ephrin-B2lacZ/+ mice. A: Quantification of WT projection topography (circles, ipsilateral; squares, contralateral) as a function of TZ center (%CNIC) vs. dye placement center (%LSO). Similar positive linear regression slopes verify topographic mapping of both inputs, such that low-frequency dye placements yield low-frequency TZs and high-frequency dye placements yield high-frequency TZs. B: Unlike WTs, ephrin-B2lacZ/+ mice have unrefined projection distributions, lack an obvious topography, and therefore show no correlation between relative TZ center and LSO dye placement location. C: Quantification of TZ size for both uncrossed and crossed LSO inputs in both WT and ephrin-B2lacZ/+ mutants. Although no significant difference is observed between projections in the two groups (P > 0.05), there is a significant difference for both inputs between WT and ephrin-B2lacZ/+ mice (*P < 0.001).