The scene where Norman (Freddie Highmore) checks the guest registry with Sheriff Green (Brooke Smith) mirrors a similar scene in Alfred Hitchcock's Psycho (1960) where Detective Arbogast (Martin Balsam) checks the registry for signs of Marion Crane(Janet Leigh) with a sample of her handwriting. Even the eerie turning of his head and candy corn eating are a nod to Anthony Perkins' portrayal of Norman Bates.
The last dress Norman (Freddie Highmore) puts in the box (blue & white) mirrors the exact same dress worn by Norma & himself in Alfred Hitchcock's Psycho (1960).
The end scene where Norman (Freddie Highmore) looks straight ahead at the screen is a reference to the last shot in Psycho. He had the same look on his face in the last moments of the Season 2 finale, The Immutable Truth (2014), when he passed the lie detector test.
When asked about what he's doing by Norman (Freddie Highmore), Chick (Ryan Hurst) tells him he's writing a suspense novel that might be turned someday into a movie. The story in fact is the story of Norman and his mother, which is what Psycho (1960) is about.