Studies in primates have shown there to be 2 main visual afferent pathways (magno and parvo) operating in parallel with different functional roles. Disease state may selectively affect one or other of these, as shown by particular sensory losses. In cases of treated Cuban tropical “neuropathy” (a retinopathy also occurs) visual acuity and achromatic contrast sensitivity are preserved although colour vision is severely affected indicating selective preservation of the “magno” pathway. In Melanoma Associated Retinopathy, red-green colour vision is preserved although achromatic contrast sensitivity for low spatial frequencies, and the detection of motion is damaged suggesting preferential damage to the “magno” pathway. Our studies illuminate two controversial aspects of the P and M systems: the role of type II parvocellular cells in colour vision and the role of M cells in detecting stimuli of low spatial and low temporal frequency.
LivingstoneM.S., HubelD.H.Psychophysical evidence for separate channels for the perception of form, colour movement and depth.J Neurosci1987; 7: 3416–68.
2.
KaplanE., ShapleyR.M.The primate retina contains two types of ganglion cells, with high and low contrast sensitivity.Proc Natl Acad Sci USA1986; 83: 2755–7.
3.
PurpuraK., KaplanE., ShapleyR.M.Background light and the contrast gain of primate P and M retinal ganglion cells.Proc Natl Acad Sci USA1988; 85: 4534–7.
4.
WatanabeM., RodieckR.W.Parasol and midget ganglion cells of the primate retina.J Comp Neurol1989; 289: 434–54.
5.
PolyakS.L.The retina.Chicago: U Chicago Press1941; 421.
6.
LeeB.B., PorkornyJ., SmithV.C., MartinP.R., ValbergA.Luminance and chromatic modulation sensitivity of macaque ganglion cells and human observers.J Opt Soc Am A1990; 7(12): 2223–36.
7.
DerringtonA.M., LennieP.Spatial and temporal contrast sensitivities of neurones in lateral geniculate nucleus of macaque.J Physiol (Lond)1984; 357: 219–40.
8.
QuigleyH.A., DunkelburgerG.R., GreenW.R.Chronic human glaucoma causing selectively greater loss of large optic nerve fibres.Ophthalmology1988; 95: 357–63.
9.
DranceS.M., LakowskiR., SchultzerM., DouglasG.R.Acquired color vision changes in glaucoma 1981.Arch Ophthalmol1981; 99: 829–31.
10.
YuT.C., Falcao ReisF., SpileersW., ArdenG.B.Peripheral color contrast: a new screening test for preglaucomatous visual loss.Invest Ophthalmol Vis Sci1991; 32: 2779–89.
11.
MullenK.T., PlantG.T.Colour and luminance in human optic neuritis.Brain1986; 109: 1–15.
12.
PlantG.T.Disorders of colour vision in diseases of the nervous system. In: FosterD.H., ed. Inherited and acquired colour deficiences: fundamental aspects and clinical studies.Basingstoke: Macmillan press1991.
13.
Grupo Operativo Nacional Ciudad de la Habana.Neuropatia epidemica en Cuba. 30 de Julio de 1993; 36.
14.
RomanG.C.An epidemic in Cuba of optic neuropathy, sensineural deafness, peripheral sensory neuropathy and dorsolateral myeloneuropathy.J Neurol Sci1994; 127: 11–28.
15.
ThomasP.K., PlantG.T., BaxterP.J., Santiago LuisR.An epidemic of optic neuropathy and painful sensory neuropathy in Cuba: clinical aspects.J Neurol1996 (in press).
16.
StrachamH.On a form of multiple peripheral neuritis prevalent in the West Indies.Practitioner1897; 59: 417–84.
17.
MadanD.Notas sobre una forma sensitiva de neuritis perifica. Ambliopia por neuritis óptica retrobulbar.Crónica Médico-Quirúrgica de la Habana.1897; 24: 81–6.
18.
BersonE.L., LessellS.Para-neoplastic night blindness with malignant melanoma.Am J Ophthalmol1988; 106: 307–11.
19.
AlexanderK.A., FishmannG.A., PeacheyN.S., MarcheseA.L., TsoM.O.M.“On” response defects in paraneoplastic night blindness with cutaneous malignant melanoma.Invest Ophthalmol Vis Sci1992; 33: 477–83.
20.
MilamA.H., SariJ.C., JacobsonS.G., LobinskiW.P., FeunL.G., AlexanderK.R.Autoantibodies against retinal bipolar cells in cutaneous melanoma-associated retinopathy.Invest Ophthalmol Vis Sci1993; 34: 91–100.
21.
ArdenG.B., GunduzK., PerryS.Colour vision testing with a computer graphics system.Clin Vis Sci1988; 2: 303–20.
22.
SwansonW.H., WilsonH.R., GieseC.G.Contrast matching data predicted from contrast increment thresholds.Vision Res1984; 24: 63–75.
23.
ArdenG.B.An overview of the uses and abuses of electrodiagnosis in ophthalmology.Int J Physiol1994; 16: 113–9.
24.
WolfJ.E., LustyN.G.Rotating stripes provide a simultaneous display of sustained and transient channels.Spatial Vision1994; 8: 369–79.
25.
MeriganW.H.Chromatic and achromatic vision of macaques: role of the P pathway.J Neurosci1989; 9: 776–83.
26.
SchillerP.H., LogothetisN.K., CharlesE.R.Functions of the colour opponent and broad band channels of the visual system.Nature1990; 343: 68–70.
27.
RodieckR.W.Which cells code for colour? In: ValbergA., LeeB.B., ed. From pigments to perception: advances in understanding visual processes.1991; 83–93.
28.
WeiselT.N., HubelD.H.Spatial and chromatic interactions in the lateral geniculate body of the rhesus monkey.J Neurophysiol1966; 29: 1115–56.
29.
WolfJ., ArdenG.B.Selective loss of magnocellular function in a patient suffering from melanoma- associated retinopathy (MAR).J Physiol1994; 475: 42p.
30.
WolfJ.E., ArdenG.B.Selective magnocellular damage in melanoma-associated retinopathy: a comparison with congenital stationary night blindness (unpublished data).
