Neurocognitive Disorders 595Perceptual-motor 
(includes abilities 
subsumed under 
the terms visual 
perception,  visuo-
constructional,  
perceptual-motor,  
praxis,  and gnosis ) Major:  Has significant difficulties with previously familiar activ-
ities (using tools, driving motor vehicle), navigating in familiar 
environments; is often more confused at dusk, when shadows 
and lowering levels of light change perceptions. 
Mild:  May need to rely more on maps or others for directions. 
Uses notes and follows others to get to a new place. May find 
self lost or turned around when not concentrating on task. Is 
less precise in parking. Needs to  expend greater effort for spa-
tial tasks such as carpentry, assembly, sewing, or knitting.Visual perception: Line bisection tasks can be used to detect basic 
visual defect or attentional neglect. Motor-free perceptual tasks 
(including facial recognition) require the identification and/or 
matching of figures—best when task s cannot be verbally mediated 
(e.g., figures are not objects); some require the decision of whether 
a figure can be “real” or no t based on dimensionality.  
Visuoconstructional:  Assembly of items requiring hand-eye coordina-
tion, such as drawing, copying, and block assembly. 
Perceptual-motor:  Integrating perception with purposeful movement 
(e.g., inserting blocks into a form board without visual cues; rap-
idly inserting pegs into a slotted board).
Praxis:  Integrity of learned movements, such as ability to imitate 
gestures (wave goodbye) or pant omime use of objects to command 
(“Show me how you would use a hammer”).