Academy in the Public Square

When technology “sees” the path for us, our sense of sight is no longer just a tool of survival — it’s a window into pleasure.

USC Dornsife Spatial Sciences Institute, notes that all cultures have developed practices for wayfinding, which involves figuring out where you are and how to get where you need to go.

Inuit hunters in the Canadian Arctic provide an example of how sharply developed our visual perception can become in the service of wayfinding. Amid the snowy landscapes of the Igloolik region, few topographical landmarks stand out to differentiate routes. Young Inuit learn through years of tutoring by elders to orient themselves by attending to visual cues as subtle as snowdrift shape and wind direction. Amazingly, up until the recent adoption of GPS devices, the Inuit had no concept of being “lost.”

If you’ve ever felt directionally challenged without your mapping app — or gotten lost even while using one — you’re probably aware that digital tools are eroding our visual attentiveness to navigational cues in the landscapes we traverse. Bernstein points to research linking GPS use to lower spatial cognition and poorer wayfinding skills.

But she cautions against demonizing the technology, arguing that GPS tools can function as visual “prostheses” that augment our powers of sight. GPS can help those with visual or spatial impairments navigate the world independently. For sighted individuals, mapping apps can facilitate a shift in visual attention from the “how” of navigation to an appreciation of the sights along the route.

“If I can just get in the car and drive, I can look at the fog and the Golden Gate Bridge,” says Bernstein of letting GPS guide her around the Bay Area. In other words, when technology “sees” the path for us, our sense of sight is no longer just a tool of survival — it’s a window into pleasure.

CHASING BEAUTY Our visual system is designed for delight. The neural pathway that extends from the retina to the occipital cortex contains opioid receptors, which, when activated, trigger a cascade of chemical changes linked to feelings of pleasure.

The late Irving Biederman, Harold Dornsife Chair in Neurosciences, and professor of psychology and computer science, and director of USC Dornsife’s Image Understanding Laboratory, explained this neural system in a previous issue of USC Dornsife Magazine. “When [our eyes] are not engaged in a deliberate search, such as looking for our car in a parking lot,” he said, “they are directed towards entities that will give us more opioid activity.”

Gazing at beautiful things — natural vistas, compelling artworks, attractive people — stimulates our brain’s reward system and makes us feel good. But the old adage is also true: Beauty is in the eye of the beholder.

According to Schwarz, individuals develop an aesthetic preference for visual stimuli that they find easy to process. In one of Schwarz’s experiments, subjects were given a list of words to learn. In one group, the word “snow” was on the list; in the other, the word “key” was featured. Both groups were then shown pictures of a snow shovel and a door with a lock. Those in the “snow” group rated the shovel as prettier; those in the “key” group rated the door as more attractive.

“Any variable that makes processing easier increases perceived beauty, even if it’s a variable that has nothing to do with beauty,” says Schwarz.

In addition to neurochemical and cognitive factors, cultural norms also influence what we see as beautiful. When viewing paintings or sculptures, we often prize the sophistication of an artist’s vision — a sort of “inner eye” that interprets what it sees in a unique way. But USC Dornsife’s Kate Flint, Provost Professor of Art History and English, explains that artistic and social norms of each era influence both the creation and reception of art.

“Beauty in a work of art … is incredibly culturally determined,” she says. “There are conventions of what constitutes the beautiful at certain times, which then get upended by other generations, other traditions.”

SEE FOR YOURSELF Romantic poet William Blake once mused on the possibility of seeing a world in a grain of sand. He was alluding to not only the grandeur but also the knowledge we can access with our powers of sight — if we pay close enough attention.

Of course, with the naked eye, we can’t actually see the (microscopic) world in a grain of sand or, for that matter, the (telescopic) world in a speck of celestial light. Our desire to know and understand truths beyond our visual limits has driven the development of increasingly powerful sight-enhancing technologies.

State-of-the-art telescopes have offered astrophysicists like USC Dornsife Dean Amber D. Miller the opportunity to visualize faraway stars and look back in time. The first images released from NASA’s James Webb Space Telescope earlier this year revealed the presence of never-before-seen galaxies, whose light originated more than 13 billion years ago — around the time of the Big Bang. Miller has likened such images to “‘baby pictures’ of the cosmos.”

Much closer to home, USC Dornsife scientists are making profound leaps in microscopy. At the USC Michelson Center for Convergent Bioscience, the cryo-electron microscopy core facility that opened last year is enabling researchers to glimpse molecules as tiny as individual proteins. And the Translational Imaging Center (TIC), based at USC Dornsife and USC Viterbi School of Engineering, is at the forefront of developing new tools that enable scientists to watch the biological processes of cells as they are unfolding — building microscopes that can collect technicolor images with a speed and sensitivity once thought impossible. TIC researchers can watch the circuit changes in the brain that accompany learning down to the single synapse level. Their collaborators at Keck School of Medicine of USC, Brian Applegate and John Oghalai, are even able to observe and measure the nanometer-sized movements in the human cochlea, part of the inner ear, as it converts sound to neuronal signals.

These technological advances are making it possible for biologists to see the eye itself in impactful new ways. Scott Fraser, Provost Professor of Biological Sciences, Biomedical Engineering, Physiology and Biophysics, Stem Cell Biology and Regenerative Medicine, Pediatrics, Radiology, Ophthamology and Quantitative and Computational Biology, directs the TIC. He and his team have been able to peer into an animal’s eye as it takes shape and forms connections in the brain. Recently, Fraser and his team have turned their tools to the human eye, observing the changes wrought by age and disease. Their hope is that better understanding the eye’s cellular processes can lead to new treatments for vision-robbing diseases like macular degeneration and diabetic retinopathy.

Fraser’s research captures the fragility of sight and its strength all at once. Our eyes may be susceptible to a host of pathologies, but they also have the potential to bring clarity to life’s greatest mysteries.

HEAR, HEAR!

Whether it takes the form of a rousing rock concert, a friendly greeting or the lulling buzz of cicadas on a summer evening, sound holds the power to energize us, to cheer us, to soothe us and —above all — to connect us.

By Meredith McGroarty

When Ludwig van Beethoven began losing his hearing as a young man in 1798, he blamed it on a fall, though modern researchers believe illness, lead poisoning or a middle ear deformity could have been factors. Whatever the cause, the hearing impairment did nothing to sweeten the acclaimed composer’s notoriously sour disposition, understandably contributing to his melancholy and ill temper.

Today, more than 200 years after the onset of Beethoven’s hearing problems, we know far more about the nature of sound and the causes of hearing loss. We also better understand how the brain comprehends language, and the power of music to affect brain activity.

But if we now have the means to protect against certain diseases that affect hearing, solutions to address the most common cause of hearing loss, aging, have been more challenging. The effects of aging on hearing can be slowed or partially ameliorated without biomedical devices, but they cannot be reversed — yet.

NEW HOPE FOR THE DEAF USC Dornsife’s Charles McKenna, professor of chemistry, believes he, along with scientists at Harvard Medical School’s Massachusetts Eye and Ear Institute, may have discovered a drug to repair inner ear cells that are damaged not only from aging, but from prolonged exposure to noise. This drug has the potential to treat damaged areas without being washed away by the ear’s natural fluid — a crucial breakthrough.

McKenna explains that neural sensors turn the vibrations we perceive as sounds into electrical impulses that the brain can register and decipher. When these sensors are damaged, hearing loss and other issues occur.

“A nerve can send a signal to the brain that lets the brain say, ‘This is a Mozart composition’ or ‘This is someone speaking,’ ” McKenna says. “The theory is that if you could regenerate the neural sensors, you would restore hearing to those who have lost it. Though there are drugs that appear to have the ability to induce regeneration of these neural sensors, successfully deploying those drugs has been a tremendous challenge.”

First, the cochlea, the part of the inner ear where damaged cells are located, is bony, making it difficult for drugs to adhere to it. Second, even if a compound is shown to attach to the structure, the inner ear’s naturally occurring fluid tends to wash it away before it can work.

Based on encouraging findings from their latest study, McKenna says he and his colleagues are optimistic their compound will adhere to the cochlea long enough to be effective. With more research, they hope to prove its efficacy.

THE POWER OF MUSIC While Beethoven struggled with hearing problems, his music, perhaps paradoxically, may help improve the brain functions of others.

Assal Habibi, head of the Brain & Music Lab at USC Dornsife’s Brain and Creativity Institute and associate professor (research) of psychology, explores how music and song affect brain activity using data collected through electroencephalography and neuroimaging. She and her colleagues have found that music can have several quantifiable benefits for the human brain, particularly in children. For example, playing music can help children hone their concentration skills.

“Music training helps with what is known as speechin-noise perception — for example, when you’re in a noisy environment and someone is calling your name or saying something you need to hear,” Habibi says. “This is a crucial ability for children in a noisy classroom who need to be able to hear the teacher and tune out background noise.”

Music training has also been shown to help some children reach developmental milestones faster. If ongoing research can establish the connection, music training might be able to prevent the onset of certain behavioral and learning issues and lead to new therapies for children who struggle with them.

“One hypothesis is that if music can assist children in reaching developmental milestones faster, for example if they develop language skills earlier, they will be able to better express their feelings and communicate more effectively,” Habibi says.

THE SCIENCE OF LANGUAGE While music therapy can help individuals sharpen their ability to discern the signal from the noise, linguistics is the discipline that deals with how we create and process the signal — speech itself.

Linguists specialize in the building blocks of language, or how sounds combine to create a word that is understood by different people, despite the fact that no two people will speak a word completely identically. Dani Byrd, professor of linguistics at USC Dornsife, examines how the vocal tract creates and combines these sounds in everyday speech, and how languages evolve to structure these sounds for encoding information.

“As a linguist I ask, ‘What are the rules that languages use to build their structures, to build their words and phrases? How do they differ from language to language?’ And I look at how and why we can understand these sounds as we do.”

Byrd says our complicated and incredibly nuanced sense of hearing mirrors a corresponding complexity in how we shape our words and sounds to convey meaning.

“The sensory cells of the inner ear are the most sensitive mechanoreceptor of the body. They have movements on a nanometer scale,” she says. “When air pressure fluctuations move your eardrum, that creates movement and an electrochemical cascade inside the inner ear.”

Our sense of hearing has the power to move us in a myriad ways. It also has the power to inspire wonder at its many — as yet — still unsolved mysteries: Why is it that we understand a gasp as a signal of surprise, or possibly fear? Why does the key of D minor often provoke feelings of sadness in one listener but not another? And how is it that our brain can take these vibrations of air and transform them into words, emotions or messages?

“Isn’t it amazing,” says Byrd, “that these tiny fluctuations in air pressure can make you laugh or cry, can convey urgency, can make you fall in love?”