L- and M-cone ratios and magnocellular sensitivity in reading.

It has been proposed that magnocellular deficits cause the reading problems in dyslexia. However, how magnocellular deficiencies are supposed to cause these problems is unclear. Recently it has been proposed that reading performance is limited by the L-/M-cone inputs to the magnocellular system. However, as explained in this review, this is problematic for a number of reasons. Particularly difficult is the linking of L- and M-cone sensitivity specifically to the magnocellular system.