Tonality affects mood

A study was performed whereby students were split into two groups. Each group listened to the same philosophical essay being read out aloud. One group listened to the essay being read in a happy tone. One group listened to the essay being read in a sad tone. The group listening to the happy tone emerged slightly happier. The group listening to the sad tone emerged slightly sadder. They then listened to the same essay whilst performing a task to distract them. They could no longer understand the meaning of the essay, but their moods were still affected in the same way.