Summary: Tests for Migraine, Optic Nerve, and Retina - electrophysiology.
"Ghost" images merge under bright light, white squares appear blue,
lines start dancing in the strobe light.

Hi,

I had some vision tests performed on me today courtesy of the local
hospital. They checked my optic nerve I believe and retina and checked
me for migraines using various flashing lights and electrodes.

The first test used a strobe light that flashed every half second for
two minutes. Quite boring. Nothing interesting to report there.

Then I was shown a monitor with black and white squares, and a red dot
stuck on the middle. The squares kept alternating between black and
white and progressively got smaller.

Again, they tested each eye separately, and I had a hard time focusing
on the dot, and sometimes I saw a blue haze around the dot in the white
squares.

I presume though, this is probably some trick of the eye more than
anything wrong?

They then asked me stare at the strobe light again with both eyes.
Again, this was pretty boring, but this time, the flashes were quicker.
On the quickest strobe rounds, I started noticing dancing lines in the
strobe light.

Is that normal? The guy there seemed to indicate it was.

Then Im shoved in basically a box with a goldfish bowl in it. It has a
chin rest for me to stick my face in, a white background, and three
black dots in the distance.

Im left in the dark for two minutes, then they, spark a light for a
fraction of a second. As the light dissipates from my retina, I see the
shadow of the dots remain for a few seconds.

They then light the background with a dull "yellow" light. Took me a
while to adjust to that, rather bright.

Under the yellow light however, I noticed there was a "ghost" shadow of
the black dots that were positioning themselves a little down and a
little right, and therefore overlapping. They start a blue spark,
nothing significant.

Then they start this really bright white light and that ghost image,
then merges with the real dot.

I mentioned everything I noticed to the guy running the test, but he
hasn't really told me anything in return. Im sort of led to believe
every test checked out normal.

Am I looking at some other issue then?

Cheers
simon