Summary of connectivity rule for inputs into pinwheels of orientation preference.
Left: A minicolumn within a pinwheel can be ascribed polar coordinates (r,q) indicating that it is located at a radius r from the singularity p, and with an orientation preference q.
Right: Such a minicolumn will receive inputs from a region in the visual field at a radius R and overlying a line passing through P with orientation of Q. The pinwheel itself is located at point P in the global retinotopic space. The relationships between points in the local map (lower-case letters ) and points in the global map (upper-case letters) is specified by equations 7 and 8. The rule describes the idealized case and in practice the input mapping is a noisy version of this ideal case.