When we listen to music, most of us respond instinctively to the rhythm and groove of a track. But a new study from the Center for Music in the Brain at Aarhus University in collaboration with the University of Bari and Italian rehabilitation centers, shows that people with substance use disorders – specifically heroin and cocaine abuse – respond differently to music than non-users.

“People with substance use disorders – whose dopaminergic reward systems have been reshaped by long-term drug use – showed distinct responses to music not only compared to control participants, but also compared to other groups with disrupted dopamine systems, such as individuals with Parkinson’s disease or those with musical anhedonia,” says Assistant Professor Jan Stupacher from the Center for Music in the Brain at Aarhus University, who’s one of the researchers behind the study.

The research focused specifically on the experience of groove – the pleasurable urge to move to music – in users of heroin and cocaine, both of which strongly impact the brain’s reward system. The results suggest that the way music with different levels of rhythmic and harmonic complexity interacts with movement, reward and motivation varies depending on conditions that affect our dopamine system.

“We found that people in therapy for heroin and cocaine addiction experienced more groove with complex rhythms and harmonies than those without addiction. We believe this can be linked to changes in their reward systems, which have adapted to the intense dopamine surges caused by drug use. This makes it harder to feel pleasure or motivation from simple everyday rewards and may explain why drug users want a bit more complexity and intensity in music,” Jan Stupacher explains.

The science of groovin’

Once the music is blasting and you’re getting your groove on you're probably not thinking about whether you’re having the ideal groove experience. But researchers have in fact found a way to describe the grooviest of grooves.

The concept is surprisingly un-funky – but an inverted U-curve is used to illustrate groovieness, explains Jan Stupacher:

“The ideal groove experience is often found in rhythmic patterns that strike the perfect balance between predictability, through a clear beat, and little surprises that disrupt the regular structure. These rhythmic patterns are typically of moderate complexity. In contrast, very simple or overly complex rhythms tend to result in weaker groove experiences: simple rhythms lack the excitement of surprise, while overly complex rhythms make it difficult for listeners to find the beat in the first place.”

And while the differences between users and non-users are subtle, they’re still significant enough to suggest a different approach to music therapy for people addicted to heroin and cocaine, says Jan Stupacher:

“Our findings may help therapists make informed decisions about the types of acoustic stimulation that are most effective when working with individuals with substance use disorders. Experiencing groove together can act as a strong social glue and understanding which types of music induce the strongest groove can help harness this potential in therapeutic settings.”

Behind the research - more information

• Studytype: Basic research, behavioral research
• Collaborators: Center for Music in the Brain, Aarhus University and Department of Education, Psychology, Communication, University of Bari
• Funding: Center for Music in the Brain is funded by the Danish National Research Foundation, University of Bari (Horizon Seed: S04), Fondazione con il Sud (2018-PDR-01136), Politiche del Lavoro, Istruzione e Formazione Department of Apulia Region (5a0c6925)
• Read more in the scientific paper: https://www.pnas.org/doi/10.1073/pnas.2502656122

Contact

Assistant Professor Jan Stupacher
Aarhus University, Department of Clinical Medicine, Center for Music in the Brain
Mail: stupacher@clin.au.dk

Professor Elvira Brattico
Aarhus Universitet, Institut for Klinisk Medicin, Center for Music in the Brain
Mail: elvira.brattico@clin.au.dk