by ian807 » Tue 29 Nov 2011, 14:50:30
$this->bbcode_second_pass_quote('Heineken', 'I')an, I carefully read the Wiki description of phosphenes. I don't think phosphenes are what I'm "seeing," since "mechanical, electrical, or magnetic stimulation" isn't involved (I'm familiar with those phenomena). I can see them with my eyes open while looking into a dark corner, or at something dark indoors, and even while looking at lighter objects. Strong light tends to tone them down.
They seem to form sort of the ground substance of the visual field.
My vision is very good; I don't think I have any pathology or strange issues. I think that everyone sees these things but isn't aware of it. They're there, but you're so used to them that you have no awareness of them.
Well, I always assumed they were phosphenes. The electrical activity in this case, just happens to be in your nervous system. The fact that they don't change in relation to external circumstances indicated that. Floaters are another matter, but they're obviously different. You're correct though. They're there all the time as a "ground substance of the visual field", but most people have habituated to them and cognitively filter them out as noise. Perceiving them is a matter of retraining your visual attention slightly. Staring at an empty blue sky is a nice way to do that, as I recall from my more leisurely teenage years.
They're not very useful though. I use them as a ballpark measure of central nervous system arousal. An additional cup of coffee or two, or any stimulating drug, changes the "look and feel" of them (i.e. more frequent, faster, a few more colors). Hallucinogens boost phosphene production too, and the concomitant reduction of inhibitory pathways will form them into pictures if you look a while. Other than that, I've never been able to get anything useful out of them.