Fig 1.
A. During task blocks dedicated to spontaneous motor action, only a central fixation point was shown. B. During task blocks during which we measured the pupil light reflex, two rectangles flanked the fixation point and varied in luminance over time.
Fig 2.
Intervals between consecutive self-paced motor actions.
Aggregate distribution including all participants, for hand movements (left) and foot movements (right).
Fig 3.
Rate of fixational saccades surrounding self-paced motor actions.
Fixational saccade rate (across-participant average and standard error) as a function of time relative to hand movements (left) and foot movements (right). Dark bars near the x-axis designate periods of significant deviation from baseline. Light rectangles designate time windows that are used for extracting summary statistics (see panel B and also main text).
Fig 4.
Pupil size surrounding self-paced motor actions.
Pupil diameter change rate (across-participant average and standard error) as a function of time relative to hand movements (left) and foot movements (right). Dark bars near the x-axis designate periods of significant deviation from 0 mm/s. Light rectangles designate time windows that are used for extracting summary statistics (see Fig 5 and main text).
Fig 5.
Association, across individual motor actions within participants, between movement-related modulation of fixational saccade rate and pupil size.
Multiple linear regression results with event-related fixational saccade rate modulation as the response variable. Standardized regression coefficients were computed per participant. ‘Interval pre’ and ‘interval post’ correspond to the time periods that separate the current motor action from the previous and subsequent one, respectively. Bars and error bars show means and standard errors across participants, respectively.