Figure 7

(A) Thresholds for optical activation via a RWM-positioned optical fibre or an apically-positioned optical fibre in C57BL/6 mice from the neonate AAV-injection group plotted against the percentage of neurons expressing ChR2-H134R-EYP in the middle turn (left; R² = 0.91, p = 0.003) or apical turn (right; R² = 0.19, p = 0.99) (n = 6). ChR2-H134R-EYFP transgenic mice with expression in all SGNs (100% of SGNs expressing ChR2-H134R-EYFP) are also shown for comparison (dark blue; n = 4). (B) Spatial tuning curve widths for electrical (red) or optical (blue) stimulation applied to the RWM or the apex of the cochlea. The width of the spatial tuning curve was measured at d’ = 1 above threshold or d’ = 2 above threshold where available. Spread of activation for transgenic mice are shown for comparison (darker blue). Box and whisker plots show median, first and third quartiles and the minima and maxima. Individual mice are symbol-coded. Basal turn data from ChR2-H134R-EYFP mice are a subset of the data presented in³⁵.