Brain me, Amadeus
Many were skeptical when research first suggested that listening to Mozart
can make you smarter. But further studies have shown that there may indeed
be strong links between the great man's work - not to mention other forms
of music - and human intelligence.
GARY KLIEWER New Scientist
Wednesday, December 1, 1999
The excitement started six years ago when researchers reported that people scored better on a standard IQ test after listening to Mozart. But last summer, the "Mozart Effect" suffered a setback when several skeptics repeated the original study and failed to find any improvement.
This is not the end of the story. A closer look shows that Mozart's music does have a profound effect on the brain, though no one knows why. Rats raised on Mozart run through mazes faster and more accurately. People with Alzheimer's disease function more normally if they listen to Mozart; the music even reduces the severity of epileptic seizures.
The first hint of the Mozart Effect emerged more than a decade ago from early efforts to model brain activity on a computer. In simulations by neurobiologist Gordon Shaw at the University of California at Irvine, the way nerve cells were connected to one another predisposed groups of cells to adopt specific firing patterns and rhythms. These patterns, he believes, form the basic grammar of mental activity. In 1988, Dr. Shaw and his student Xiaodan Leng decided to turn the output of their simulations into sounds instead of a conventional printout. To their surprise, the rhythmic patterns resembled like baroque, new-age or Eastern music. "I don't mean it was great music, but we got distinct, recognizable styles," Dr. Shaw says.
If brain activity can sound like music, he wondered, might we learn to understand the neural grammar by working backwards and watching how the brain responds to music? In other words, might patterns in music prime the brain by activating similar firing patterns of nerve clusters? If so, Dr. Shaw thought he knew where to start: Mozart, a prodigy who began composing at age four. "We thought if anyone might be tapping into this inherent neural structure, it might be Mozart."
So Dr. Shaw and his colleague Frances Rauscher, now a psychologist at the University of Wisconsin at Oshkosh, decided to use part of a standard IQ test to see whether Mozart's music could temporarily boost people's ability to visualize shapes. This ability forms the basis of many complex thinking skills, including much of mathematics.
In their largest study, published in 1995, Dr. Shaw and Dr. Rauscher asked 79 college students to work out the appearance of a paper if it were folded, then cut like a paper doily. After taking the test, one group of students sat in silence for 10 minutes. Another group listened to a Mozart piano sonata. A third group heard either an audiotaped story or minimalist, repetitive music. Then they all took the test again.
The Mozart group correctly predicted 62 per cent more shapes on the second test, while the "silent" group improved by 14 per cent and the third group by just 11 per cent. It is this experiment that has drawn so much criticism from other researchers.
Kenneth Steele, a psychologist at Appalachian State University in Boone, N.C., repeated the experiment but found no sign that Mozart's music improved the scores of 125 subjects.
But the critics are looking at only part of the story, says Lois Hetland of the Harvard Graduate School of Education. She cast a broader net that included every study to date, a total of 1,014 subjects. She found that Mozart listeners outperformed other groups more often than could be explained by chance, although the effect was usually much weaker than Dr. Shaw and Dr. Rauscher saw.
A converted skeptic is psychologist Eric Seigel at Elmhurst College, Illinois, who set out to disprove the Mozart Effect by using a different spatial reasoning test. In his experiment, a subject looks at two letter E's, with one rotated at a skewed orientation in relation to the other. The greater the angle, the harder it is to judge whether the letters are the same or different. The milliseconds it takes the subject to make that judgment are a precise measure of spatial reasoning. To Dr. Seigel's surprise, subjects who took the test after listening to Mozart did significantly better.
For the sake of consistency, almost all studies on the Mozart Effect so far have focused on a single piece of music, the Sonata for Two Pianos in D Major (K 448), though some have measured the effect from other music. "It is not just this composition, and not just Mozart," says Dr. Rauscher. However, researchers don't know why the Sonata in D works or which other pieces might. Would the music of Mozart's contemporary Johann Christian Bach work, or even that of a 20th-century composer such as Igor Stravinsky? One study did show that the music of a popular new-age composer, Yanni, had an effect.
Critics take issue with this vagueness, saying that someone has to define what specific musical elements are required.
Studies yet to be published may help clear up this problem. At the University of Illinois Medical Center, neurologist John Hughes and a musicologist colleague have analyzed hundreds of compositions by Mozart, Chopin and 55 other composers. They devised a scale that scores how often the music's loudness rises and falls in surges of 10 seconds or longer.
Minimalist music by composer Philip Glass and pop tunes scored among the lowest on this measure, Dr. Hughes found, with Mozart scoring two to three times higher. He predicts that sequences repeating regularly every 20 to 30 seconds may trigger the strongest response in the brain, because many functions of the central nervous system, such as the onset of sleep and brain-wave patterns, also occur in 30-second cycles. And of all the music analyzed, Mozart's most often peaks every 30 seconds, Dr. Hughes found. Results such as these may help predict which pieces of music have the strongest effect on the brain.
Meanwhile, another of Dr. Shaw's collaborators, Julene Johnson of the Institute of Brain Aging and Dementia at the University of California at Irvine, gave Dr. Shaw's original paper-folding test to Alzheimer's patients, who often have impaired spatial reasoning. In a pilot study, one patient's scores improved by three or four correct answers out of eight test items after 10-minute doses of Mozart, but not after silence or hearing popular music from the 1930s.
"The popular tune was familiar to the patient and intended to account for a possible emotional effect of music versus silence," says Dr. Johnson. She has followed up with a group study comparing Mozart versus silence in 18 patients. Though results are not yet published, Mozart did improve the patients' test scores, especially in people who showed little improvement after practising the test.
Even stronger support for Mozart's effect on the brain comes from other studies.
Dr. Rauscher, for example, subjected 30 rats to 12 hours of the Sonata in D daily for over two months. The rats ran a maze an average of 27 per cent faster and with 37 per cent fewer errors than 80 other rats raised with white noise or in silence, she found. The improvement can't be due to enjoyment arousal, because rats have no emotional response to Mozart. Instead, the study suggests a neurological basis for the Mozart Effect, says Dr. Rauscher.
She does acknowledge that Mozart may simply give the rats a richer, more stimulating environment, something the rats could also get from other distractions or activities. "The control group rats are severely deprived -- an extreme condition," she admits. She has begun a new study comparing rats with the heavy Mozart diet to rats given plenty of social interaction and toys in their cages.
Still, there must be something special about Mozart's music, and not just for rats. Dr. Hughes studied 36 severely epileptic people who suffered almost constant seizures that sometimes left them comatose.
For 29 of those patients, the debilitating electrical storms that swept their brains became smaller and less frequent shortly after he began playing Mozart. The same patients showed no improvement while they listened to a Glass composition, 1930's pop tunes, or silence. "Sceptics could criticise the IQ studies," Dr. Hughes says, "but this is on paper: you can count discharges and watch them decrease during the Mozart music." And in comatose patients, at least, the effect cannot be dismissed as an enjoyment arousal.
Another study, by Dr. Shaw and neurobiologist Mark Bodner of the University of California at Los Angeles, mapped the regions of a subject's brain that respond while listening to Mozart, pop music or Beethoven's Für Elise. Not surprisingly, Dr. Bodner found that all music activates the auditory cortex, where the brain processes sound, and sometimes triggers parts of the brain that are associated with emotion.
"But with Mozart, the whole cortex is lighting up," Dr. Bodner says. Specifically, only Mozart also activates areas of the brain involved in fine motor co-ordination, vision and other higher thought processes, all of which might be expected to come into play for spatial reasoning.
But these short-term improvements may not be Mozart's most important effect on the brain. In a five-year study with children, Dr. Rauscher has found that keyboard-music training improves skills that require mental imagery -- and after two years of lessons, the effect doesn't wear off. "All of the Mozart Effect experiments are based on the idea that the brain can be anatomically influenced by music. With children it may be actually building the neural network," says Dr. Rauscher. In other words, a childhood rich in music may have lasting benefits. This may be finally where the Mozart Effect makes its real encore.