FIG. 3.

Transformation of the yz plane into a set of orthogonal axes defining a modiolar-pillar dimension and a habenular-cuticular dimension. A The original yz projection from Fig. 1A is reproduced here along with the transformed modiolar-pillar and habenular-cuticular axes for this z-stack. B To produce the new modiolar-pillar axis, the best-fit straight line is computed to the set of zy coordinates of the centroids of the ribbon component of each synapse. The habenular-cuticular axis is made orthogonal to the best-fit line. The origin is placed at the median value for the set of 172 ribbon positions from this stack, as expressed along each of the new axes. These data are for the 11.3 kHz z-stack illustrated in A. C Data for all the z-stacks obtained from control ears in the 11.3 kHz region: each case has been normalized to the median y and z values, but the axes have not been transformed. Data are extracted from 2 stacks from each of 10 ears (from 10 animals), for a total of 3,411 synapses. D Same data as in C, but now the axes have been transformed for each case and then superimposed.