HPPD induced synesthesia

[SamL]

I got a mild case of HPPD 5 months ago from the use of muchrooms. After I realized I got HPPD, I didn't use any drugs and I am pretty much cured now. I barely notice anything beside very mild static when I wake up and very weak closed eyed hallucinations if I am tired.

A few weeks ago, I noticed that I was seeing colors on graph paper. For example if I look at the image below, the lines turn green and purple and the hexagons fill with a faint shade of orange and blue:

http://www.cadcourse.com/winston/Images/TCW90INI/HONEYCOMB.gif

Could this be related to HPPD? Has anyone experienced something similar? I worried that if HPPD didn't cause this, it might be a brain tumor or something. I am considering going to my doctor to get an MRI or something but I don't want to make a big deal out if it in case it's nothing to worry about.

[cs1234]

does it happen with other patterns?

[SamL]

does it happen with other patterns?

Yes. It happens with linear patterns. It's less noticeable if the lines are thick and pretty much unnoticeable if the image is colorful. The image I posted works really well because the lines are so thin and black.

For example, this image doesn't work whatsoever:

http://www.lyrois.com/blog/i/lrs-ss08-wp-original-1.jpg

But this one works really well to the point where not only the lines are colorful, but the squares fill up with different shades. The cool thing is if I zoom in or out, all the colors suddenly shift:

http://3.bp.blogspot.com/-Y5sXRf9d60I/Tb4fiH9qCgI/AAAAAAAAFqM/4OV_Df3uOpU/s1600/graphpaper.gif