Jan-Nikolas Klanke^1,2 (), Sven Ohl¹, Martin Rolfs^1,2; ¹Humboldt-Universität zu Berlin, ²Berlin School of Mind and Brain

Feeling of agency (FoA)—the experience of control over actions and their outcomes—has been extensively studied for bodily movements, but it remains unclear whether it extends to eye movements. Here we utilized small, ballistic eye movements called microsaccades to examine if such visual actions are characterized by FoA and whether intention mediates this feeling of control. We measured FoA for microsaccades using effect binding: a perceived compression between an action and its effect. In our experiments, we presented a vertically oriented grating, rendered invisible during stable fixation by a rapid temporal phase shift (>60 Hz) that became visible when its retinal motion was slowed by a microsaccade (active condition). The stimulus was presented embedded in a clock face and observers reported perceived stimulus timing in each trial. We compared the perceived timing of microsaccade-contingent stimuli to that of stimuli resulting from replaying a previous microsaccade’s retinal consequences (replay condition). Trials without a stimulus were included as a control. To examine the role of intention, we tested this paradigm across two experiments: In Experiment 1, observers were instructed to either saccade or fixate, leading to intended (microsaccade instruction) and unintended (fixation instruction) microsaccades. In Experiment 2, no instruction was administered and microsaccades were labelled as spontaneous. Microsaccades rendered the stimulus perfectly visible, with visual sensitivity substantially higher in trials with generated or replayed microsaccades compared to those without, in particular when microsaccade direction and peak velocity matched direction and speed of the stimulus. Temporal estimates did not differ between active and replay conditions for any microsaccade type. Thus, we found little evidence for temporal binding of an eye movement to its sensory consequence. This data does not support that microsaccades are accompanied by a phenomenally distinct feeling of control, nor that FoA for small eye movements is facilitated by intention.

Acknowledgements: JNK was supported by the Berlin School of Mind and Brain, Humboldt-Universität zu Berlin. SO was supported by the DFG (OH 274/4-1) and its Heisenberg Programme (OH 274/5-1). MR was supported by the ERC under the Horizon 2020 program (grant agreement 865715), and the DFG (RO3579/8-1 and RO3579/10-1).