Soundings: brain ‘closes eyes’ to hear music
Our brains can turn down our ability to see to help them listen even harder to music and complex sounds, say experts.
A US study of 20 non-musicians and 20 musical conductors found both groups diverted brain activity away from visual areas during listening tasks.
Scans showed activity fell in these areas as it rose in auditory ones.
But during harder tasks the changes were less marked for conductors than for non-musicians, researchers told a Society for Neuroscience conference.
Dr Jonathan Burdette Wake Forest University Baptist Medical Center
The researchers, from Wake Forest University Baptist Medical Center and the University of North Carolina, used functional Magnetic Resonance Imaging, which can measure real-time changes in brain activity based on the blood flow to different areas of the brain.
Previous research has identified various parts of the brain involved in vision and hearing.
The experiment involved 20 professional orchestral conductors or band leaders and 20 musically untrained students, all aged between 28 and 40.
While lying in the scanner, they were asked to listen to two different musical tones played a few thousandths of a second apart and identify which was played first.
The task was made harder for the professional musicians than for the non-musicians, to allow for the differences in their background.
What the scientists found was that while activity rose, as expected, in the auditory part of the brain, it correspondingly fell in the visual part.
As the task was made harder and harder, the non-musicians carried on diverting more and more activity away from the visual parts of the brain to the auditory side, as they struggled to concentrate.
However, after a certain point, the conductors did not suppress their brains, suggesting that their years of training had provided a distinct advantage in the way their brains were organised.
Dr Jonathan Burdette, who led the study, said: “This is like closing your eyes to listen to music.
“Imagine the difference between listening to someone talk in a quiet room and that same discussion in a noisy room – you don’t see as much of what’s going on in the noisy room.”
Another researcher, Dr David Hairston, said that the study showed just how flexible this ability was.
“How this operates can change with highly specialised training and experience,” he said.
Dr Bahador Bahrami, from the UCL Institute of Cognitive Neuroscience, said the study showed the difference in “brain organisation” between musicians and non-musicians.
“It demonstrates the mechanisms developed in the brain in the face of distraction. The brains of the conductors are highly tuned to tones.”
Source: BBC News