Abstract
A hollow face does not normally look as it really is, hollow; but looks convex especially if viewed from a distance. It is difficult to recognize the identity and the emotional expression in an upside-down face. One explanation is that global face processing only occurs for upright faces. Here video faces expressing emotions are projected onto an upright and an upside-down structureless white mask. When the upright mask is viewed at close proximity with two eyes from the normal side, the facial expressions are clearly discernable. But when viewed from the hollow side — when it looks hollow — the emotional expression is not easy to read. Emotional expressions are not clearly discernable (as expected) when the upside-down mask is viewed either when normal or hollow. Experiments will be reported quantifying these effects.