The Kiki and Bouba effect highlights a connection between how we perceive sounds and shapes. It reveals a tendency for people to consistently associate specific sounds with particular visual forms. This phenomenon suggests that certain speech sounds naturally align with certain shapes, indicating a non-random link in our perception.
Understanding the Kiki and Bouba Effect
German-American psychologist Wolfgang Köhler first observed the Kiki and Bouba effect in 1929. He presented participants with two abstract shapes—one spiky and angular, the other rounded and curvilinear—and asked them to match these with nonsense words like “takete” and “baluba.”
Participants overwhelmingly paired the spiky shape with “takete” and the rounded shape with “baluba.” In 2001, researchers Vilayanur S. Ramachandran and Edward Hubbard repeated this experiment using “Kiki” and “Bouba.” Across diverse groups, including American college undergraduates and Tamil speakers, 95% to 98% linked “Kiki” to the jagged shape and “Bouba” to the rounded shape. This high agreement across different languages and age groups highlights the universal nature of this sound-shape correspondence.
The Science Behind Sound-Shape Correspondence
The Kiki and Bouba effect’s consistent associations stem from cross-modal correspondence, where the brain links information from different senses. Articulatory movements play a role: “Kiki” involves a taut, angular mouth shape, while “Bouba” involves a rounded one. This physical sensation may influence the visual association.
Acoustic properties of the sounds also contribute to these associations. “Kiki” sounds involve higher frequencies and abruptness, aligning with sharp features. Conversely, “Bouba” sounds are lower in frequency and smoother, mirroring soft curves.
Neural pathways in the brain may also be involved, with studies suggesting congruent sound-shape pairings enhance neural responses in visual processing areas. The Kiki and Bouba effect is a form of sound symbolism, where sound features are non-arbitrarily mapped to meanings or objects, and is distinct from synesthesia.
Real-World Applications and Other Examples
The Kiki and Bouba effect has practical applications in various fields. In branding and marketing, companies leverage this when choosing product names or designing logos. “Kiki”-sounding names or angular designs convey precision or modernity, while “Bouba”-sounding names or rounded designs suggest comfort or friendliness. For instance, “Knix” might evoke a spiky, modern image, whereas “Oodie” could suggest something round and soft.
The effect also influences product design, aligning an object’s shape with its intended perception. It contributes to language development, particularly in onomatopoeia, where words mimic sounds. Words like “sizzle” or “crunch” naturally convey their associated sounds, demonstrating an inherent sound-action link. Other sound-shape associations exist; for example, the “gl” sound often relates to slipperiness, and the “p” sound can be associated with puffiness.