Kathmandu— Constantina Makridakis, a 28-year-old jewelry designer from Greece, grew up believing everyone tasted voices and names; her father’s name, Nicholas, tasted like caramel-coated chocolate, while her mother’s, Maria, evoked pasta with prawns. It wasn't until late in her teens that she learned this experience was not universal, but rather a neurological phenomenon called synesthesia, where stimulation of one sense triggers experiences in another. Affecting an estimated 2 to 4 percent of the population, synesthesia manifests differently for each individual and offers insights into how we all perceive the world.

A Perceptual Variation

Synesthesia is a perceptual phenomenon with diverse expressions; American singer-songwriter Billie Eilish experiences days of the week as colors, numbers, and shapes. Historically, composer Franz Liszt also believed he had synesthesia, reportedly instructing musicians to play “a little bluer” in 1842 while perceiving musical notes as colors. Janina Neufeld, a researcher at the Centre of Neurodevelopmental Disorders at Karolinska Institutet in Sweden, explains that while these experiences may seem unusual, most people have internal sensory associations.

The Brain's Unique Connections

Researchers estimate that 2 to 4 percent of the population experiences some form of synesthesia, with many unaware their perceptions differ from others. Neufeld herself experiences spatial sequence synaesthesia, visualizing a year as an undulating circle in her mind’s eye. The neurological basis of synesthesia isn't fully understood, but one theory suggests that individuals with synesthesia may experience less synaptic pruning during childhood—the process where unused neural connections are eliminated—allowing for more cross-sensory connections to remain. Studies have shown increased brain activation and interaction between different regions in people who experience synaesthesia.

Everyday Life with Synesthesia

Makridakis describes how her synesthesia can be both stimulating and distracting; an actor’s voice tasting like orange juice during a film, for example. It also influences cravings—the American accent tastes like Coca-Cola, leading to increased desire for the drink while in the United States. She associates US President Donald Trump with melted cheddar cheese, British actor Daniel Radcliffe with chocolate milk, and hip-hop artist Eminem’s voice with Cheetos. Despite occasional overstimulation, Makridakis is fascinated by her perceptions and believes further study could deepen our understanding of the human mind.

Makridakis hopes increased research into synesthesia will reveal more about the complexities of the human brain and how individuals uniquely experience the world around them.

(With inputs from Al Jazeera)

Originally published on abcnews.com.np.