Action affordance affects proximal and distal goal-oriented planning.

Visual attention is mainly goal directed and allocated based on the upcoming action. However, it is unclear how far this feature of gaze behaviour generalizes in more naturalistic settings. The present study investigates the influence of action affordances on active inference processes revealed by eye movements during interaction with familiar and novel tools. In a between-subject design, a cohort of participants interacted with a virtual reality controller in a low-realism environment; another performed the task with an interaction setup that allowed differentiated hand and finger movements in a high-realism environment. We investigated the differences in odds of fixations and their eccentricity towards the tool parts before action initiation. The results show that participants fixate more on the tool's effector part before action initiation when asked to produce tool-specific movements, especially with unfamiliar tools. These findings suggest that fixations are made in a task-oriented way to plan the distal goals of producing the task- and tool-specific actions well before action initiation. Moreover, with more realistic action affordance, fixations were biased towards the tool handle when it was oriented incongruent with the subjects' handedness. We hypothesize that these fixations are made towards the proximal goal of planning the grasp even though the perceived action on the tools is identical for both experimental setups. Taken together, proximal and distal goal-oriented planning is contextualized to the realism of action/interaction afforded by an environment.