Here is the full list of all 38 Psychonauts trophies - there are 21 bronze, 12 silver, 4 gold and 1 platinum.
Complete Meat Circus.
Sort all Emotional Baggage.
Introduce all Camp Kids to Mr. Pokeylope.
Re-brain the Children.
Complete The Asylum.
Uncover Milla's Secret.
Redeem all 16 Scavenger Hunt Items.
Complete Black Velvetopia.
Find all Golden Helmets.
Achieve Rank 80.
Earn all Merit Badges.
Find Edgar's Secret Garden.
Complete Waterloo World.
Complete Gloria's Theater.
Achieve Rank 60.
Complete The Milkman Conspiracy.
See yourself through the eyes of many others.
Use the bacon. A lot.
Complete Lungfishopolis.
Achieve Rank 40.
Spy on Bobby's love life.
Cook and consume two different kinds of roast in one sitting.
Hear Vernon's Ghost Story.
Complete Milla's Dance Party.
Achieve Rank 20.
Complete Sasha's Shooting Gallery.
Buy an item from the Camp Store on Christmas.
Give the Coach's speech on the stump.
Read many bulletin board messages.
Discover the secret history of Whispering Rock.
Complete Basic Braining.
Unlock all trophies.
Achieve Rank 101.
Crack all Vaults.
Gather all Figments.
Witness Maloof's transformation.
Revisit all brains after completion.
Complete the Punchy Target mini-game.