> rail stations in Japan began installing these LED panels as a suicide-prevention measure Another technique they use is to play recorded birdsong and other "sounds of nature" at some open-air stations, which supposedly makes people feel more peaceful and relaxed. It's quite subtle, random and realistic-sounding and caused me quite a lot of confusion looking for the invisible birds before learning the truth!
The point of the bird sounds is to help visually impaired people find the exit (notice it's always coming from where the escalator starts).
Anyway, my information is from a friend whose uncle works at Tokyo Metro, and has seen his fair share of jinshin jiko maguro. She was quite clear about the notion that it was an anti-suicide measure, and I believed her. I did only notice it on the Saikyou line.