Imagine chatting with a friend as they recount their day, which included a trip to the movies with some delicious popcorn. As you picture this, you can almost hear the popcorn popping, smell its irresistible aroma, and savor the buttery taste. Yet, your friend’s mention of going to the movies on a Friday triggers an unexpected reaction in your mind—a rush of the color orange. You might wonder why orange is making an appearance in this narrative. Maybe the popcorn bucket is orange or the walls of the movie theater you frequent is orange? But no, it’s simply the word “Friday” that has been associated with the vibrant hue of orange in your sensory perception for as long as you can remember. This unique way of perceiving the world, where words or concepts evoke sensory sensations in unrelated ways, is known as synesthesia. It is a fascinating condition where stimulation in one sensory pathway can lead to involuntary experiences in a different sensory pathway. It highlights the rich diversity of human perception.
What is Synesthesia?
Synesthesia is a unique sensory condition that defies the typical activation of our senses. The hallmark of synesthesia is the ability of the brain to process sensory information through multiple unrelated senses, leading to the simultaneous experience of more than one, seemingly unrelated, sense. Synesthesia affects about 2-4% of the global population. The brain regions that can be involved in synesthesia include the visual cortex, auditory cortex, and motor cortex which are all involved in sensory perception. The manifestations of synesthesia vary widely among individuals. For some, it’s an interesting, infrequent experience. However, for others, it can be a highly intense experience that occasionally interferes with daily life, though these cases are exceptionally rare.
Researchers are still investigating the underlying causes of synesthesia, with three key factors including brain development, brain damage, or drug use emerging as potential triggers of alterations in sensory perception. It’s been suggested that all individuals experience synesthesia to some extent during childhood, with many of us gradually losing this ability as we grow older. Moreover, there’s a growing understanding people with synesthesia tend to have more interconnected brain regions. This occurrence might also be linked to the higher prevalence of synesthesia in individuals with autism spectrum disorder. In addition to developmental factors, brain damage has been observed to induce short-term synesthetic effects. Furthermore, the use of psychedelics, such as LSD and Psilocybin (also referred to as magic mushrooms), has been shown to temporarily alter sensory perception.
Various Forms of Synesthesia
As a complex sensory condition, researchers have identified over 150 different forms of synesthesia. Among these numerous variations, there are seven common forms including hearing-motion, day-color, and sound-color synesthesia. Sound-color synesthesia is a form of the condition where a person hears musical notes or sounds and sees specific colors. Many well-known musicians have correlated their musical talents to their sound-color synesthesia including Pharrell Williams, Duke Ellington, Lady Gaga, and Lorde.
Sensory perception is an important factor in how we experience the world day-to-day. Those who experience synesthesia have an altered version of what most would consider typical sensory perception as many of their sensory pathways are intertwined. What do you think, would you be interested in experiencing synesthesia?
Peer Editor: Elissavet Chartampila