Figure 1.

Distinguishing parasol cells by axon conduction velocity. Histograms show axon conduction velocity estimates for 216 of the 946 cells in a single recording, including: 59 OFF-parasol and 40 ON-parasol cells (top); 83 OFF-midget and 18 ON-midget cells (middle); and 2 small bistratified cells and 14 cells of other types (bottom). The remaining 730 cells were excluded on the basis of too few axonal electrodes for an accurate estimate, or a spatial pattern of axonal electrode locations suggestive of a polyaxonal cell [28]. ON-parasol cells and OFF-parasol cells tend to have higher axon conduction velocities than other cell types [27, 32].