- "He's got flu and some Third years accidentally plastered frog brains all over the ceiling of Dungeon Five; he's been cleaning all morning..."
- —Nick on Argus Filch[src]
A frog brain is much like that of a human, but the cerebrum is relatively smaller. In 1992, some third years accidentally plastered frog brains all over the ceiling of Dungeon Five, a Potions dungeon. The use of frog brains in Potions remains unknown.