Psycho World has 4 play modes you can cycle through when you press F4. It's undocumented but can give extra enjoyment. They are:

• Normal Mode
• Maxup Mode
• Power Mode
• Extra Mode

The game starts in Normal Mode.

Extra Mode is identical to Normal Mode, with the difference that it allows access to Talk Mode by pressing F5.
In Talk Mode conversations are started. Normal Mode has a few texts which are extended in Talk Mode.

Maxup Mode is a strange mode. It'll increase the H.P and ESP bars beyond the visible part. It will also decrease your protection against the environment. Your H.P will decrease much more, so be careful.

Power Mode is very much like a cheat mode. It'll activate the number keys on the keyboard (not the numeric pad) to restore H.P and ESP, or power up one of the ESP powers. The numbers are like:

7 2 6
5 1 3
8 4 9


0 = refill H.P and ESP
1 = power up Psy-Cannon
2 = power up Hydro Wave
3 = power up Burning-Bullet
4 = power up Cooling-Down
5 = power up Ultra-Sonic
6 = increase Levitation count
7 = increase Teleportation count
8 = increase Explorsion count
9 = increase Shield/Exchange count

Full playthroughs can be found in the Psycho World YouTube Playlist.