These are the findings in Lassi A. Liikkanen’s doctoral dissertation. According to Liikkanen, imagined music is a unique mnemonic phenomenon different from other types of involuntary memory. The phenomenon is a universal characteristic of human information processing, inseparable from other processing of musical information. It is present also in the everyday life of many people, even though their attention is drawn to it only occasionally. If the phenomenon persists or the episodes include unwanted music, it starts to be noticed.
The dissertation suggests answers several related questions: how prevalent is imagined music, how is it usually expressed and what kind of factors affect it. Liikkanen also tackles issues surrounding the prevention and suppression of imagined music. He presents various solutions and assesses their impact on the basis of evidence gained in the study.
Liikkanen has compiled the results of his investigations, launched in 2007, and combined them with other research in the field. He has had a central role in turning the phenomenon into an internationally recognised research topic. Over the past 15 years, the number of publications in the field has increased from a handful to nearly 50. In the academic world, hearing music in one’s head is also known as involuntary musical imagery, while earworm is the colloquial term.
The title of Lassi A. Liikkanen’s doctoral dissertation is Involuntary Musical Imagery – Everyday but Ephemeral. The dissertation falls under the fields of cognitive science and music psychology.