Perceptual lengthening of visual time throughout learning of hand-reaching actions

Timing is intimately woven into human cognition and behavior, yet the dynamic interplay between timing and action remains poorly understood, particularly during goal-directed action learning. Using combined behavioral, electroencephalographic, and modeling approaches, we investigated how perceptual time changes as participants gained experience in a goal-directed reaching task requiring different degrees of action planning. Participants judged brief visual durations while preparing hand movements toward visual targets. Subjective time expanded during action preparation, which gradually increased across trials mirroring gradual improvements in action readiness. Representational similarity analysis revealed dissociable neural responses linking action and timing: action planning influenced time encoding during timed stimulus presentation, whereas broader motor engagement shaped subsequent time decoding following stimulus presentation. These findings extend previous accounts of action-dependent changes in perceived time, showing that the interaction is dynamic, evolving with changes in action readiness, and is mediated by dissociable neural responses during time encoding and decoding stages.