Looking at planar views during active object visual learning: moments of stability

Abstract

The planar bias in active object learning is a well-documented viewpoint selection preference: in adults, and infants, the proportion spent looking at planar views – viewpoints where flat surfaces are shown perpendicular to the viewer – deviates strongly from random selection. One hypothesis of the planar bias’ functional role is that dynamic viewing around them is more informative – movements around planar views reveal more of the objects’ structure; this hypothesis predicts more exploratory behaviours, for instance measurable in higher angular velocities of the main axis of elongation. We asked adults to manipulate 3D objects on a computer, using a mouse, for twenty seconds each, and recorded the object’s 3D orientation and eye fixations (60Hz). We computed, per contiguous frames of dwell activity, inside a bin of the object’s viewing sphere: duration, proportion of time with object not moving, mean angular velocity of the main axis, and number of saccades. Results show that counter to the initial prediction, viewing periods around planar views are more stable: duration is higher, time not moving is higher, main axis speed is lower, and there are more saccades. Put together, these findings suggest focused attention to planar views and learning of a static view.