Oviya Mohan¹, Dora Biro¹, Jude Mitchell¹; ¹University of Rochester

Gaze following, the ability to direct one’s attention to the target of another’s, plays a key role in social interactions and can help individuals attend to relevant locations and events in their environment. Gaze following has been considered reflexive, in which case it might operate invariant to whether or not it leads to obtaining relevant social information. Although gaze following has been demonstrated in the common marmoset (Callithrix jacchus), the stimuli used are often not representative of the natural social settings in which it typically occurs. We presented head-fixed marmosets with naturalistic stimuli (videos) of freely behaving marmosets exhibiting directed gazing as a means of eliciting reliable gaze following behavior. Each video featured a marmoset entering a center box and gazing toward a box on either the right or the left. Two trial types, one where a target marmoset appeared in the cued box and another where no target marmoset appeared in either box, were presented interleaved covering a range of +/- 10 visual degrees (previously verified to fall within the oculomotor range of marmosets). The first saccades that landed outside the center box were categorized into cued and distractor regions for valid trials (head-fixed marmoset looks at cueing marmoset). In both trial types, significantly larger number of first saccades landed in the cued region than in the distractor region (p < 0.001) confirming reliable gaze following by the head-fixed marmoset in this paradigm. We further tested if gaze following is impacted in a non-informative context. We included a novel trial type in which the cued and distractor boxes were occluded by cardboard, eliminating the possibility of viewing the entry of the target marmoset. Preliminary results show differences in gazing behavior in this context indicating that gaze following is context dependent.

Acknowledgements: Funding: NIH grant EY030998