Associating a sound with the object it refers to
Neuchâtel, July 15, 2025. A team of researchers from the University of Neuchâtel studied the ability to associate a new sound with an object, amidst a noisy but familiar environment. This cognitive faculty of rapid association is attested in humans, as well as domesticated animals like cats and dogs. This new research shows that neither gorillas nor orangutans, though they are primates like us, make use of this so-called “fast mapping” ability. The results, obtained as part of the NCCR Evolving Language, are published in the specialized review Animal Cognition.
By the University of Neuchâtel.
Dogs and cats, just like humans, are able to quickly associate a sound with an object.
The concept of “fast mapping” describes the ability to associate rapidly a new sound to an object implicitly. If you say “Oh! An apple is rolling across this table”, and the subject to whom this sentence is addressed has never previously seen an apple, he will quickly deduce that the rolling thing is an apple. The aim of the study was to observe whether subjects – humans and two other species of great apes – would associate a particular sound, emitted in a familiar hubbub, to an object located in the scene. And if so, how quickly?
Exotic fruits
The objects consisted of four images of not well-known exotic fruits, photographed on four different natural backgrounds (rocks, leaves, soil, grass), as could be seen in real life. “We chose exotic fruits in order to maintain the interest of apes and to minimize the risk of humans already knowing the name of these fruits,” states the scientific article. To avoid this latter bias, the names given to the fruits were vocables created from scratch, pseudo-words inspired by French and Swiss German.
Then comes the first stage of the experiment: the apes and the humans learn which pseudo-word each image is associated with by “fast mapping”. “During this learning phase, we show the object accompanied by “its” pseudoword, played three times,” explains Dahliane Labertonière, principal co-author of the scientific article, while she was working at the Centre for Cognitive Sciences at the University of Neuchâtel.
Eye tracking
At the moment of the test, two objects appear, each one responding to a pseudo-word that the subjects will have learned beforehand if the “fast mapping” has worked. A single pseudo-word is then played, associated with the target object. Eye tracking is used to measure the duration and the location of the gaze of the subject. “We therefore expect an increase in the duration of the gaze towards the target object at the moment of the test, which has been verified in humans, but not in gorillas nor in orangutans,” explains the researcher. “This is the first time, as far as we know, that an experiment has suggested that great apes show no signs of this ability, unlike cats and dogs.”
Thus, how can we explain these differences in sensitivity to fast mapping? “In domesticated species, the ability to quickly associate an object with a word could represent an advantage and a utility for the species in question,” Dahliane Labertonière proposes. This benefit can, for example, be seen when cats or dogs interact with humans by playing with objects like a ball or a ball of yarn, objects that these animals should rapidly identify if they want to continue the interaction.
To be confirmed results
Great apes stay however wild animals and could simply not need this ability. “In their natural habitat, it is probably not necessary for their survival to be able to quickly associate sounds with food,” suggests the researcher, whose work follows on from her doctoral thesis at both the Comparative Cognition Laboratory and the Institute for Logopedic Sciences. “It could be different if we were interested in the ability to associate a specific sound with a danger, for example, as mentioned in scientific studies on alarm calls in primates,” suggests Dahliane Labertonière.
The team of scientist insists on pointing out the limitations of their research, which needs to be furthered and confirmed. They include only a small number of subjects tested, which limits the statistical generalisation of the results: five humans, four gorillas, and one orangutan. Another limitation was the difficulty subjects had to stay focused on the task, especially great apes, which limited the learning of new sound-object associations.
