Vita gazette – Like humans, monkeys like to take their souls for a stroll with music, to calm their disembodied soul, or to turn it into an exuberant waterfall. Recent research has revealed that monkeys prefer to listen to music rather than watch.

Recent research on animal-computer interaction by the University of Glasgow in England and Aalto University in Finland revealed that monkeys prefer to listen rather than watch.

The player is the latest development in ongoing zoo enrichment research from animal-computer interaction specialists at the University of Glasgow in the UK and Aalto University in Finland. The researchers set out to explore how a group of three white-faced saki monkeys at Korkeasaari Zoo in Helsinki would respond to being able to trigger audio or visual stimuli on-demand, like a primate-focused Spotify or Netflix. The system is the first of its kind to offer monkeys a choice of stimuli.

To do so, they built a computer interface contained in a small wood-and-plastic tunnel which they placed in the monkeys’ enclosure. Infrared sensors created three equally-sized interactive zones inside the tunnel. When monkeys moved through an infrared beam, it would trigger either a video or a sound on a screen in front of them which played for as long as they chose to stay.

The device was in the sakis’ enclosure for a total of 32 days. For the first seven days, the tunnel was silent to allow them to get used to its presence. For the next 18 days, they could choose between an audio or video stimulus which changed every few days. Throughout the experiment, those stimuli were rain sounds, music or traffic noise, videos of worms, underwater scenes, or abstract shapes and colours.

Each time they interacted with the system, it automatically recorded what was playing, and how long they spent in the interactive zone which triggered the content to play. Finally, for seven days at the end of the experiment, the tunnel returned to being non-interactive once more. A side view of the ‘monkey media player’ showing the hardware involved.

While the audiovisual stimuli elements of the tunnel were active, the sakis’ interactions were mostly short, lasting a few seconds each time as they walked or ran through the system – mirroring how they interact with more familiar elements in their enclosure.

The sakis triggered audio stimuli twice as much in total as visual stimuli, but over time their interactions shifted. As the study progressed, their overall levels of interaction with both stimuli dropped, but their interactions with visual stimuli increased in comparison with the audio stimuli. In total, they listened to music in most of the three audio files and watched the underwater video most frequently.

The research was led by Dr Ilyena Hirskyj-Douglas of the University of Glasgow, along with colleague Vilma Kankaanpää of Aalto University in Finland.