Music improves dopaminergic neurotransmission: demonstration based on the effect of music on blood pressure regulation
Sutoo D., Akiyama K.
Brain Res. 2004 Aug 6; 1016(2): 255-62
Institute of Medical Science, University of Tsukuba, Tsukuba, Ibaraki
The mechanism by which music modifies brain function is not clear. Clinical
findings indicate that music reduces blood pressure in various patients.
We investigated the effect of music on blood pressure in spontaneously
hypertensive rats (SHR). Previous studies indicated that calcium increases
brain dopamine (DA) synthesis through a calmodulin (CaM)-dependent
system. Increased DA levels reduce blood pressure in SHR. In this study,
we examined the effects of music on this pathway. Systolic blood pressure
in SHR was reduced by exposure to Mozart's music (K.205), and the
effect vanished when this pathway was inhibited. Exposure to music
also significantly increased serum calcium levels and neostriatal DA levels.
These results suggest that music leads to increased calcium/CaM-dependent
DA synthesis in the brain, thus causing a reduction in blood pressure.
Music might regulate and/or affect various brain functions through dopaminergic
neurotransmission, and might therefore be effective for rectification
of symptoms in various diseases that involve DA dysfunction.
The investigation of the effects of music on the neurochemistry of otherwise
well studied animals, like rats and mice, has been slow, because of widespread
doubts if music could mean anything to these animals. How could such small
animals possibly be interested in, or even affected by, strange acoustic
games of humans? If there were an effect, it would probably be acoustical
stress. Nothing could have been more wrong than this. As now reported
by Sutoo and Akiyama, music for string orchestra by Mozart shifted
the physiology of rats clearly towards relaxation or recreation. Systolic
blood pressure decreased, and various tests indicated that this was
due to an increase in serum calcium levels and brain dopamine
levels. How such effects can be triggered in rats by acoustic order
that is typical human remains a mystery. As had been suggested earlier,
the exceptional temporal order of neural activity that music exposure
causes in the auditory midbrain (inferior colliculus) may be the
most promising candidate for further investigations. Perhaps the new results
of Sutoo and Akiyama can lead to some more open-minded attitudes towards
music effects in small animals.
The music that was played for the rats was the Adagio (3rd and
slow movement) of Mozart's Divertimento in D (K205). An excerpt
of it can be heard online here
(piece No. 11, down on the playing list).