I suppose my take on this matter might be of interest? I have had periods of temporary blindness.
For me, my normal eyesight is slightly stunted in one eye, and severely in the other. I don't wear
glasses, but I probably should. I don't drive, but I probably should get some glasses and learn how.
My blind periods have been usually tied to a migraine, often lingering after the migraine, sometimes
for days or weeks. At first, my doctors thought that I was going blind, as the blind periods were
increasing in both frequency and duration. I was preparing to go blind. Funny how I was so eager to
learn how to cope with living blind that I didn't take time to grieve the expected loss or to revel
in the sight that I supposedly had left to me. I have always had light sensitivity, poor eyesight,
and exceptional other senses; I suppose that this new development in my ever-challenging state-of-
physical-being seemed natural. Turns out that it was mostly due to the migraines that were triggered
by an odd food allergy. I like birds well enough, but I should never eat them. No poultry for me.
I still have migraines, mostly managed. I still have blind periods, rarely; only for hours, not days.
What first happens to my sight is that everything becomes brighter, and the light hurts more during
the migraine. For that matter sound and smell and touch also seem amplified and hypersensitive/painful.
It's like the light being reflected off of every surface increases. Interestingly, the more reflective
surfaces (mirrors/windows/etc.) in a room, the more light I seem to register. The light isn't reflected
IN the reflected surface, but in the room itself - each object. Don't ask me to explain why; I have no
clue? Eventually the light takes over, and does it ever hurt! I think that after enough over-stimulation
my eyes begin to shut down/cease registering what is too painful to perceive. Sometimes its like tunnel
vision that eventually has no light at the end; other times I just dim several shades of grey, slowly going
black. The migraine pain often begins to ease after I have gone black, reduced other sensory stimuli, and
relaxed into a quiet breath-focused semi-meditative state or fallen asleep. Sadly, medication is mostly
ineffective. The black used to linger after the migraine pain was over, like I said, for days or weeks...
However, now that I am a pescatarian, the black doesn't linger; it fades back to sight as the pain eases.
While learning to adjust to living blind, I learned a lot. Many that I spoke with seemed to have a limited
sense of sight/light. If you held a light near their eyes, and then removed that light, there was a sense
of the light change for some. I had a mentor that was blind from birth; he had no sense of light or colour
of any visual kind, BUT he could read/see people better than anyone I have ever known.He was a psychologist.
I do think that the sense of visuality (yes I made that word up; Shakespeare did it all the time) may exist
for a blind person even if they were born blind, depending on what the cause for their blindness might be.
On another note, I have known folks who speak and think in more than one language. I have also known people
who do not normally think in words, rather more like impressions (so they say). Everyone is so different
that I have come to believe that we all think (and perceive) differently to some degree (synesthesia, for
example), but rarely are in a position to compare these sorts of abstract things.