Elizabeth N. Johnson, Michael J. Hawken and Robert ShapleyNat. Neurosci. 4, 409–416 (2001)

Part of a sentence in the legend to Fig. 7 was omitted. The correct figure legend appears below. We regret the error.

Fig. 7. Histograms of the L- and M-cone phase differences from the L- and M-cone isolating frequency responses for all simple cells in the population. (a) The phase differences for neurons responding predominantly to equiluminance (color cells). (b) The phase differences for neurons responding predominantly to luminance (luminance cells). (c) The phase difference for neurons responding comparably to both chromatic equiluminance and luminance (color-luminance cells).