on 10/16/02 5:40 PM, Stephen Black at [EMAIL PROTECTED] wrote: > In doing some more web-browsing, I see that my terminology in my last > post equating monochromaticity with achromatopsia is likely > incorrect. In fact, I first wrote it using the term > "monochromaticity" and changed it to "achromatopsia" after spotting > it on the web and thinking it was the preferred term. > > But in sometime TIPSter Hugh Foley's book (Sensation and Perception, > 4th), he defines achromatopsia as loss of color vision due to damage > to the central nervous system.. Monochromaticity he defines > functionally as only requiring one color to match perception of all > others. I think I probably should have stuck with monochromaticity in > my post.
Ok, this is all from memory & just a very brief look on the web: but I understood the term achromatopsia to refer specifically to people who have only rods and no cones at all (as distinct from people who have only one type of cone). A quick look on PubMed seems to support that, but I won't swear to it. Now, I see you have another post that straightens out the other terminology, so I won't go into that. But here's something very picky about Hugh Foley's definition, just for the heck of it (I don't know if he's around to respond). Way back in graduate school, I'd swear I was taught that the retina is considered part of the central nervous system (that the cells there have characteristics typical of the CNS, and that the retina is actually an extension from the brain). If my memory is correct, then I'd say that all color deficiencies result from a problem in the CNS, and so I'm not sure of his definition. John -- John Serafin Psychology Department Saint Vincent College Latrobe, PA 15650 [EMAIL PROTECTED] --- You are currently subscribed to tips as: [EMAIL PROTECTED] To unsubscribe send a blank email to [EMAIL PROTECTED]
