Hearing is believing

Hearing is believing


Writer Joyce Kilmer once wrote that he would never see a poem as lovely as a tree.

He likely would never hear a poem as lovely either, especially since scientists are revealing just how tightly knit seeing and hearing are in our brains.

The blurring of the sensory borders of the brain became strikingly apparent when researchers from the University of Glasgow discovered evidence that the brain’s visual cortex … once thought to only receive input from the eye … is also processing sound.

Neuroscientists focused powerful brain-imaging machinery on the brains of blindfolded volunteers, who were listening to a variety of sounds, such as birdsongs, traffic clamor or people talking in a crowd.

They discovered the different sounds were being processed in a region called the “early” visual cortex. That’s the first place that receives information from the retina before forwarding it through the visual system.

The new connection was unheard of … never before had this part of the visual cortex been known to process sound.

The researchers suggest that by incorporating auditory information with the visual, our brains help us predict and make sense of what we are about to see.

Taking the experiment a step further, the researchers asked the volunteers to simply form mental images.

Even without sight and sound, imagination was enough to stir the visual cortex.

Scientists are intrigued that the brain’s visual system can be activated by sound and imagination.

Better understanding of the interconnectivity of the different brain regions may help better explain psychiatric conditions such as in autism or schizophrenia, where sensory information is often misinterpreted.

In the meantime, the scientists say their next step is to use a larger variety of auditory inputs to stimulate the visual systems of the volunteers.

That sounds like it will be quite a sight.

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