Toronto, Jan 8 (IANS) The very few people who do not like music at all may have reduced brain connectivity between two regions of the brain linked to sound processing and reward.
The findings showed that people who lacked joy from music -- a condition described as specific musical anhedonia -- had reduced functional connectivity between cortical brain regions responsible for processing sound and subcortical regions related to reward.
The inability to experience pleasure from music affects three-to-five per cent of the world's population, the study said.
For the study, the team led by researchers at McGill University in Quebec, Canada, recruited 45 healthy participants who listened to musical excerpts inside an fMRI machine while providing pleasure ratings in real-time.
To control their brain's response to other reward types, the participants also played a monetary gambling task in which they could win or lose real money.
The results revealed that while listening to music, people with the specific musical anhedonics did show reduced functional connectivity between cortical regions associated with auditory processing and the activity of the nucleus accumbens -- a key subcortical structure of the reward network.
In contrast, individuals with high sensitivity to music showed enhanced connectivity.
Moreover, when the participants won money in the gambling task, their nucleus accumbens showed increased activity.
The fact that subjects could be insensible to music while still being responsive to another stimulus like money suggests different pathways to reward for different stimuli.
This finding may pave the way for the detailed study of the neural substrates underlying other domain-specific anhedonias and, from an evolutionary perspective, help us to understand how music acquired reward value.
"These findings not only help us to understand individual variability in the way the reward system functions, but also can be applied to the development of therapies for treatment of reward-related disorders, including apathy, depression, and addiction," said Robert Zatorre, neuroscientist at McGill University, Quebec.
The study was published in the journal Proceedings of the National Academy of Science