Abstract
We can perform the same action with more or less "vigor" (e.g., walking to a good friend we haven't seen in a while versus walking after a long day) — and this phenomenon applies even to visual actions, i.e., eye movements. But as the speed of eye movements increases with higher vigor, sensory information also arrives at a faster rate, which might leave an inflexible system unable to catch up. Here we ask whether and how the visual system can flexibly adapt to the vigor of the actions that ultimately deliver its inputs. We manipulated the vigor of eye movements by varying the pace of saccade targets appearing and disappearing from view. Saccades of the same range of amplitudes were performed with higher velocities in high-pace than in low-pace conditions. We then assessed the consequences of this vigor induction across stages of visual processing. First, to test what breaks through into conscious awareness in the first place, observers pressed a key as soon as they saw a face in a repeated mask suppression experiment (e.g., Abir & Hassin, 2020). Observers showed a traditional face inversion effect (with faster breakthrough times for upright versus inverted faces) in high-vigor but not in low-vigor trials, suggesting that eye movement vigor may facilitate the effective prioritization of meaningful stimuli. Second, to test the speed of meaning extraction, observers reported whether they saw a particular concept (e.g., a dog) in rapid serial visual presentation (RSVP) streams (e.g., Potter et al., 1976; 2014). Detection rates increased with presentation durations (from 13ms to 80ms) — but this curve was shifted upwards and leftwards in high-vigor compared to low-vigor trials. Thus, the vigor of eye movements alters the efficiency of visual processing — from what enters awareness to how we extract meaning from incoming sensory information.