Musical Beat Enhances Visual Comprehension

New research finds a link between musical rhythm and visual processing, and offers a tantalizing clue to the art form’s origins.

By Tom Jacobs, Miller-McCune.com

The origins of music are, necessarily, speculative. Charles Darwin guessed it grew out of courtship rituals, which would explain the continuing popularity of love songs. But a more recent school of thought suggests it emerged to enhance group cooperation and synchronization.

As neuroscientist Steven Brown put it, “Music is a powerful device for promoting group identity, cognition, coordination and catharsis.” All of which would come in handy when a party of prehistoric humans headed out in search of food or when one tribe was threatened by another.

Indirect support for this thesis is provided in a study just published in the journal Acta Psychologica. In it, a research team led by psychologist Nicolas Escoffier of the National University of Singapore provides evidence that a musical beat “both synchronizes and facilitates concurrent stimulus processing.”

Their research suggests rhythm (say, in the form of a drum beat, which continues to play a role in military rituals) helps you to quickly understand what it is you’re looking at. This could save your life if you spot a shape that could be either a lion or a rock, and its advantages multiply if you and your hunting partners come to such crucial realizations simultaneously.

Escoffier and his colleagues recruited 36 undergraduates (all of Chinese ancestry) to participate in a visual discrimination test. They were shown a series of photographs — half featuring faces, the other half houses — and instructed to indicate as quickly as possible (by pressing one of two buttons) whether an image was right side up or upside down.

They were told to ignore the music playing in the background, but those sounds were in fact the key to the experiment. For one-third of the test, the appearance of the images was synchronized with the beat. For another third, the images were shown out of sync with the music. The other third were shown in silence.

The results: The students responded faster when there was music playing, and still faster when the appearance of a new image matched the beat of the music. They were able to identify the direction of the faces more rapidly than that of the houses in all three conditions, but the same ratio held: Their swiftest reactions took place when the musical rhythm and the change in image were in sync. (The accuracy rate was around 95 percent for all three conditions; what varied was the speed of the realization.)

Why would hearing music affect visual processing? Escoffier and his colleagues suggest two possible processes. Auditory rhythms have been shown to enhance physiological arousal, which could lead to heightened attention. Alternatively, an insistent rhythm may trigger “changes in attention allocation policies,” alerting the brain to focus its limited resources on the matter at hand.

Either way, “musical rhythm appears to be a powerful modulator of human cognitive processes, enhancing their efficiency and allowing synchronization across a group of individuals,” they conclude. “Through this synchronization, individuals collectively experience their environment and are able to feel, think, and act as one.”

Thus the thrill of sitting in a concert hall and engaging in a mass brain-bond with Beethoven or Bono. To paraphrase George and Ira Gershwin: I got rhythm/And clear vision/We’re all in sync/Who could ask for anything more?