Gaze cues of human avatars trigger joint attention in macaque monkeys

Poster Session F - Tuesday, April 16, 2024, 8:00 – 10:00 am EDT, Sheraton Hall ABC

Ehsan Aboutorabi¹ (eaboutor@uwo.ca), Borna Mahmoudian¹, Julio Martinez-Trujillo¹; ¹Robarts Research Institute, University of Western Ontario

Joint attention is a fundamental ability of humans and other social primates. Gaze direction could be informative of the behavioral relevance of environmental objects. Paradigms to explore joint attention usually involve measurements of gaze in at least two subjects making it difficult to conduct with non-human primates. Here we show a novel paradigm using avatars in a virtual environment while monitoring gaze behavior and joystick responses of monkeys. We trained two rhesus monkeys to respond to a human avatar's attention by moving a joystick towards the gazed-at object. We designed social cues by applying natural eye and head movements on a highly realistic avatar. Trials began with the avatar gazing at the animal. After 500 ms, the avatar's gaze shifted towards one of four virtual objects, cuing the animal to move its joystick accordingly for a juice reward. In 10% of trials, the avatar gaze moved in a random direction between two objects. The animals successfully responded to the avatar’s gaze (90% task performance). A classifier, trained on eye positions during the 350 ms cue period, achieved 80% accuracy in predicting animal’s choice. In catch trials, accuracy decreased to 53%, because the animals directed gaze to one of the two objects closest to the avatar’s gaze position, indicating the animals still follow joint attention gaze cues. Our results demonstrate the use of human avatars in experimental setups to explore joint attention in macaque monkeys. It also demonstrates a degree of cognitive flexibility and extrapolation of human gaze cues in macaques.

Topic Area: ATTENTION: Other