Newly Hatched Chickens Show Bouba/Kiki Effect in Groundbreaking Study

Research has revealed that newly hatched chickens demonstrate a sound association similar to that observed in humans, specifically linking the sounds “bouba” with round shapes and “kiki” with spiky ones. This finding, published in the journal Science, adds a new dimension to our understanding of the bouba/kiki effect, a phenomenon first documented in 1947.

The bouba/kiki effect has long intrigued scientists. It was initially noted that people associate certain sounds with specific shapes, leading to extensive studies on the topic. Early theories suggested that these associations were tied to linguistic familiarity, but subsequent research indicated that this tendency transcends language and is likely a universal human trait. Infants as young as four months have shown these associations, yet efforts to identify the effect among other primates yielded no conclusive evidence.

In a recent study led by Italian researchers Maria Loconsole, Silvia Benavides-Varela, and Lucia Regolin, the team sought to explore whether the bouba/kiki effect extends beyond primates to other species. Their focus shifted to newly hatched chickens, which, despite being only one to three days old, are fully mobile and capable of interacting with their environment.

The researchers conducted control experiments with silence and classical music to establish a baseline for the chicks’ preferences. Notably, when the word “bouba” was played, approximately 80 percent of the chicks gravitated towards a rounded shape. Conversely, when “kiki” was introduced, this number plummeted to just 25 percent, with more chicks choosing the spiky shape instead. These outcomes were more pronounced in the three-day-old chicks but were also evident in those tested just one day after hatching.

The researchers attribute these findings to a mechanism known as “crossmodal correspondence,” where one sensory input influences the perception of another. This phenomenon is commonly observed in humans, such as associating high-pitched sounds with small objects and low-pitched sounds with larger ones. Interestingly, while this effect has been documented in various animals, such as dogs and tortoises, it had not been previously observed in chickens.

The implications of this research suggest that the bouba/kiki effect is not exclusive to species with complex language systems. Instead, it highlights that even animals like chickens can exhibit similar sound-object associations. The absence of this effect in previously tested primates may be due to the complex motivations of adult animals, which can obscure instinctual preferences.

This study not only broadens our understanding of sound associations in the animal kingdom but also challenges the notion that such cognitive abilities are unique to humans. As ongoing research continues to explore the depths of animal cognition, findings like those from Loconsole and her team pave the way for a more nuanced understanding of how different species perceive and interact with their environments.