Leibovich et al. opened up an important discussion on the nature and origins of numerosity perception. The authors rightly point out that non-numerical features of stimuli influence this ability. Despite these biases, there is evidence that from birth, humans perceive and represent numerosities, and not just non-numerical quantitative features such as item size, density, and convex hull.

Constructivist and ecological approaches are also observed in tactile perception studies. The question is whether identification and localization are dissociated in the tactile modality as well, and whether Norman's conception may be generalized to the field of touch. An analogue to blindsight was evidenced in passive touch, but no such dissociation was observed in active touch. A study is in progress in this domain.

Neonatal behavioral data support the argument that multiple relations exist between vision and touch. Looking at an object triggers the motion of a neonate's arm and hand towards it. A textured surface that is seen can be recognized tactilely, but not a volumetric shaped object in cross-modal transfer tasks. These data are supported by adult neuroimaging data.