After a cerebrovascular accident, a patient is evaluated for cognitive and perceptual dysfunction. When stacking wooden blocks, the patient cannot determine how the block should be used after picking it up. This dysfunction is MOST likely due to which condition?

After a cerebrovascular accident, a patient is evaluated for cognitive and perceptual dysfunction. When stacking wooden blocks, the patient cannot determine how the block should be used after picking it up. This dysfunction is MOST likely due to which condition?

• A. Homonymous hemianopsia
• B. Astereognosis
• C. Unilateral neglect
• D. Apraxia

Answer: (D)

Motor planning for how to use objects after a brain injury is impaired. In apraxia, a person can have intact strength and sensation but cannot perform purposeful movements or use objects correctly because the brain’s planning of the action is disrupted. Here, picking up a block but then being unable to determine its use or how to stack it shows a breakdown in conceptualizing and sequencing the motor action required to achieve the task, which is classic for apraxia. This isn’t a sensory or visual problem. A deficit like homonymous hemianopsia would involve a loss of vision in half the field of view, not an inability to plan how to use an object. Astereognosis is the inability to recognize an object by touch, despite normal vision and movement. Unilateral neglect involves ignoring stimuli on one side of space, not a general difficulty with using an object. The difficulty in figuring out how to use the block points to impaired motor planning for object use, i.e., apraxia.

Motor planning for how to use objects after a brain injury is impaired. In apraxia, a person can have intact strength and sensation but cannot perform purposeful movements or use objects correctly because the brain’s planning of the action is disrupted. Here, picking up a block but then being unable to determine its use or how to stack it shows a breakdown in conceptualizing and sequencing the motor action required to achieve the task, which is classic for apraxia.

This isn’t a sensory or visual problem. A deficit like homonymous hemianopsia would involve a loss of vision in half the field of view, not an inability to plan how to use an object. Astereognosis is the inability to recognize an object by touch, despite normal vision and movement. Unilateral neglect involves ignoring stimuli on one side of space, not a general difficulty with using an object. The difficulty in figuring out how to use the block points to impaired motor planning for object use, i.e., apraxia.