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