Research Projects

Oculomotor and attentional dynamics during visual foraging

In this research project, we are interested in the strategies used to explore efficiently a complex visual scene composed of multiple targets and multiple distractors. In situations in which individuals search for different targets simultaneously (e. g., all the red dots and green squares in the display on the right), while avoiding distractors (e. g., red squares and green dots), some people exhaust one entire target category before switching to the second target category, while others gradually proceed in the visual space keeping the two target categories in working memory throughout the experiment. The research project aims at examining oculomotor dynamics during such tasks so as to  identify how the strategies employed by observers modify their oculomotor behavior, and, reversely, how individual differences in visual exploration come with individual differences in foraging strategy.

Since 2025, this research is part of the MULTIFOR project funded by the French National Research Agency: https://anr.fr/Project-ANR-24-CE28-3988

Collaborators:

• Pr. Karine Doré-Mazars (Univ. Paris Cité)

• Ph.D student Maha Haggouch (Univ. Paris Cité)

• Pr. Árni Kristjánsson (University of Iceland)

• Dr. Laura Lazartigues (Univ. Lille)

• Pr. Stéphanie Mathey (Univ. Bordeaux)

• Pr. Christelle Robert (Univ. Bordeaux)

• Pr. Ian M. Thornton (University of Malta)

Eye movements during facial emotion recognition in children with ASD and their parents

This project, led by Prof. R. Delorme at Hôpital Robert Debré, aims at characterizing behavioral endophenotypes of autism spectrum disorders (ASD). We asked children with ASD and their parents to perform a facial emotion recognition task while recording their eye movements. Past research has shown that children with ASD make more eye fixations on the mouth than on the eyes of the emotional face, whereas children without ASD make more eye fixations on the eyes than on the mouth of the emotional face. We here investigate whether the parents of children with ASD show similar differences in visual exploration. The influence of other individual characteristics such as IQ and alexithymia are also examined.

Collaborators:

• Dr. Corentin Gosling (Paris Nanterre University)

• M. Sc. Ariane Cartigny (Neuropsychologist, Hôpital Robert-Debré, AP/HP, Paris)

• Dr. Alicia Cohen-Freoua (Psychatrist, Hôpital Robert-Debré, AP/HP, Paris)

• Pr. Richard Delorme (Hôpital Robert Debré, AP/HP, Paris)

Functional asymmetries in vision and oculomotor control

This project aims at examining how perceptual and motor asymmetries can influence attentional and oculomotor processes. Functional asymmetries such as the lateralization of visuo-spatial attention networks and the lateralization of local and global processing of visual information are considered. In other studies, we also examine how lateral preferences, such as handedness and sighting eye dominance, can play a role in perceptual and visuo-motor processes. To do so, we measure saccadic parameters in the left and right visual hemifields, in individuals with left or right handedness and sighting eye dominance. As shown in the graph on the right, our results for example show that saccade accuracy (measured in a global effect paradigm) is higher in the hemifield contralateral to the dominant eye than in the ipsilateral hemifield. Such results are discussed with regards to the neural architecture of the oculomotor system, and we show that eye dominance and perceptual asymmetries should be considered in future models of oculomotor control.

Collaborators:

• Pr. Dorine Vergilino-Perez (Paris Descartes University)

• Pr. Karine Doré-Mazars (Paris Descartes University)

• Dr. Christelle Lemoine-Lardennois (Paris Descartes University)