Molecular basis for Mozart effect revealed

From : news service

New research has revealed a molecular basis for the "Mozart effect" - the observation that a brief stint of Mozart, but not other music, may improve learning and memory.

Rats that heard a Mozart sonata expressed higher levels of several genes involved in stimulating and changing the connections between brain cells, the study showed. The team, including the researcher who first proposed the Mozart effect, hope the results will help them design music therapy treatments for people suffering from neurodegenerative diseases such as Alzheimer's.

The Mozart effect first came to light in a 1993 paper in Nature (vol 365, p 611), when Fran Rauscher, a neuroscientist at the University of Wisconsin Oshkosh, US, and colleagues showed that college students who listened to Mozart's Sonata for Two Pianos in D Major for 10 minutes performed better on a spatial reasoning test than students who listened to new age music or nothing at all.

The findings sparked excitement from the general public - specially designed Mozart CDs leapt up the music charts - and some scepticism from the scientific community.

Rhythmic qualities

Scientists argued over whether the phenomenon had a relatively simple explanation, such as just improving a person's mood, or if the effect was tied to a unique quality of the Mozart's compositions. One study reported that the particular rhythmic qualities of Mozart's music mimic some rhythmic cycles occurring in human brains.

Now Rauscher and her collaborator Hong Hua Li, a geneticist at Stanford University in California, think they have found the molecular basis of the Mozart effect. Their study used rats, which, like humans, perform better on learning and memory tests after listening to the sonata.

The researchers found that these smarter rats had increased gene expression of BDNF, a neural growth factor, CREB, a learning and memory compound, and synapsin I, a synaptic growth protein, in their hippocampus, as compared to control rats who had listened to equivalent amounts of white noise.

"The findings are intriguing," says Howard Gardner, an IQ expert at Harvard University in Cambridge, Massachusetts, and sceptic of the Mozart effect. "It suggests stimulation in general has measurable neurochemical effects. But whether this effect is due to music, let alone Mozart, still has to be determined." Other experiments have shown that enriching a rat's environment with toys can spur growth of new neurons.

Electrical activity

Whether Mozart is in fact a special form of enrichment or not, his presence is already being felt in the clinic.

Patients with Alzheimer's disease perform better on spatial and social tasks after listening to the sonata. And playing Mozart for severely epileptic patients quietens the electrical activity associated with seizures, while other kinds of music do not.

Li hopes to use this latest work to design better music therapy for patients suffering form a variety of neurological disease or brain injuries. She and Rauscher also plan to study if there is a critical period during development for the Mozart effect, and if other types of music have the same properties.

The new research was presented by at the Cognitive Neuroscience Symposium in San Francisco this week.

Emily Singer, San Francisco