Lawson, R., Boylan, A., & Edwards, L.

We investigated whether the relative position of objects and the body influenced haptic recognition. People felt objects on the right or left side of their body midline using their right hand. Their head was turned towards or away from the object and they could not see their hands or the object. People were better at naming 2D, raised line drawings and 3D, small-scale models of objects and also real, everyday objects when they looked towards them. However, this head-towards benefit was only reliable when their right hand crossed their body midline to feel objects on their left side. Thus haptic object recognition was influenced by people's head position although vision of their hand and the object was blocked. This benefit of turning the head towards the object being explored suggests that proprioceptive and haptic inputs are remapped into an external coordinate system and that this remapping is harder when the body is in an unusual position (with the hand crossing the body midline and the head turned away from the hand). The results indicate that haptic processes align sensory inputs from the hand and head even though either hand-centred or object-centred coordinate systems should suffice for haptic object recognition.

Attention, Perception and Psychophysics (2014), 76, 559-574.