What is the deal with this unusual definition of cyberspace?

[Victory_Candescence]

The Jargon File has this rather odd 3rd definition of cyberspace:

(By the way, they’re using the word “hacker” and “hack” in the old-fashioned sense of “someone good with computers” and “working with computers”, not in their negative modern senses)

http://www.catb.org/~esr/jargon/html/C/cyberspace.html

cyberspace
[…]
3. Occasionally, the metaphoric location of the mind of a person in hack mode. Some hackers report experiencing strong synesthetic imagery when in hack mode; interestingly, independent reports from multiple sources suggest that there are common features to the experience. In particular, the dominant colors of this subjective cyberspace are often gray and silver, and the imagery often involves constellations of marching dots, elaborate shifting patterns of lines and angles, or moire patterns.

What are they talking about with this business of colors and marching dots and stuff? I’ve certainly never heard of anyone experiencing anything like that.

[cankerist]

Its part of a phenomenon called synesthesia, which is not limited to hacking. Check this site.