Peripersonal and vertical neglect.

When bisecting radial lines visually, normal subjects err towards distant peripersonal space, and when bisecting vertical lines visually, they err towards upper vertical space. In contrast, when bisecting lines under tactile-proprioceptive guidance, subjects err towards near peripersonal space, suggesting that normally attention is preferentially distributed away from the body during visual exploration but distributed towards the body during tactile exploration. A patient with ischaemic lesions, however, involving both inferior temporal lobes neglected far peripersonal and upper vertical space. He also demonstrated a motor bias away from the neglected space. These findings suggest that in man attention is spatially directed in three orthogonal axes (horizontal, vertical and radial), that attention may normally be unequally distributed in each of these axes, and that neglect may occur in not only the horizontal axis but also in the radial and vertical axes.