[revolvingocelot]

>has evolved in modern literature to any item [which can] cause death when an image of them is mentally constructed

The excellent and memorable science fiction short story BLIT [0], by David Langford, is what I think of. In the story, a mathematical process called the Berryman Logical Image Technique produces images that cause segfaults in the primary visual cortex when viewed, and thereby irrevocably crash human minds.

I was introduced to the concept by the excellent The Laundry [2] series by Charles Stross ('cstross here on HN!), which features a dangerous fractal referred to as the Langford Death Parrot.

[0] http://www.infinityplus.co.uk/stories/blit.htm

[1] https://en.wikipedia.org/wiki/BLIT_(short_story)

[2] The Laundry is itself worth reading, being a ha-ha-only-serious examination of a fictional British occult secret service in a world where sufficiently advanced mathematics is indistinguishable from Lovecraftian magic, and the ever-increasing density of transistors on CPUs brings the world ever closer to CASE NIGHTMARE GREEN. The viewpoint character, for much of the series, is a sysadmin.