A loss of the ability to carry out familiar, purposeful movements even when there is no paralysis or other motor or sensory impairments: William experienced apraxia that included his inability to perform movements that are necessary to use objects properly, even when the names and purposes of the objects were known and understood.

The inability to complete a bodily movement because of a failure to recognize and to interpret sensory information upon which its performance depends: "The player attempted to swing the baseball bat and hit the baseball but was unable to do so because she experienced agnostic apraxia and could not perceive how close the ball was to her."

The inability to carry out spontaneous movements: "His akinetic apraxia limited his ability to only move his left hand because his brain could not interpret the afferent movement information or the nerves that conducted impulses from the periphery (outer surface) of his body to his brain or spinal cord."

The inability to produce a movement on command because it is forgotten, although the ability to perform the movement is present: "The woman's amnesic apraxia was demonstrated when she could do the same movements of her fingers and hands that the doctor did; however, when she was told to move her fingers and hands again when the physician didn't do it, she couldn't remember how to repeat the actions."

The inability of a person to draw from memory or from a model, or to construct simple or complex shapes with matchsticks or building blocks: "A person with constructional apraxia usually can't accomplish certain activities that involve building, assembling, and drawing."

"For those who have a mild form of constructional apraxia only the ability to draw in perspective (appearance of objects to the observer) may be lost while the capacity to make gestures and to recognize geometric symbols can be remembered."

A disorder of an ability to plan and to execute motor activities that occurs in developing children: "Developmental apraxia is thought to be a result of central nervous system immaturity that exists in youngsters."

Being unable to move an individual finger when asked to do it even when there is no paralysis: "When the woman with digital apraxia was told to hold up her index finger, she couldn't do it."

Being incapable of dressing oneself because of the person's inadequate knowledge of the spacial relations of his or her body: "As the young woman was dressing to get ready to go out, she was having difficulty with dressing apraxia; for example, simply putting on her slacks was confusing her."

A condition in which a person's conceptual process is missing, often because of a lesion in the parietal lobe of the brain which is that part of the cerebral hemisphere that lies beneath the parietal bone or the main side bone of the skull: Susan has ideational apraxia, or sensory apraxia, and is incapable of formulating certain plans for the movements of things because she doesn't know what the proper uses of the objects are.

Working in the kitchen can be dangerous when someone, like Jane, suffers from ideational apraxia and is not sure how to use kitchen equipment correctly.

A disorder in which simple acts can not be performed in sequences or a continuous series of actions: "The ailments known as ideomotor apraxia and ideokinetic apraxia handicap people because they have nervous-system disorders that result in deficits in the execution of movements due to the inability of accessing the neural instructions to the muscles."

"Those neural instructions were stored by previous motor experiences when simple-single acts could be performed but those who have ideomotor apraxias can't do a sequence of associated actions."

Incapable of performing movements that are necessary to use objects properly although the names and purposes of the objects are known and understood: "When a person has motor apraxia, there is no loss of normal motor movements or strength, but the reasons for the movements are confusing."

"Despite having a trainer, the client continued to experience motor apraxia and was unable to ride his bicycle safely."

Being unable to perform a movement involving the use of a tool, an instrument, or another object: "The man's sensory apraxia handicapped him because he couldn't determine the size, shape, and purpose of what the doctor meant when he was told to pick up a hammer, the pliers, etc."

The inability to perform complex or co-ordinated movements: "Visual apraxia takes place when an individual fails to represent spatial relations correctly as when drawing or when involved in some form of construction."