Which statement correctly distinguishes decorticate posturing from decerebrate posturing?

Which statement correctly distinguishes decorticate posturing from decerebrate posturing?

• A. Decorticate: brainstem; Decerebrate: cerebral hemispheres
• B. Decorticate: cerebral hemispheres; Decerebrate: brainstem
• C. Decorticate: cerebellum; Decerebrate: spinal cord
• D. Decorticate: frontal lobe; Decerebrate: occipital lobe

Answer: (B)

Posturing patterns reflect where motor pathways are disrupted. In decorticate posturing, the disruption is above the red nucleus, typically involving the cerebral hemispheres or internal capsule. This causes the upper limbs to flex (often with adduction) while the legs extend. In decerebrate posturing, the injury is at or below the red nucleus in the brainstem, leading to loss of cortical inhibition on brainstem pathways and producing an overall extension of the arms and legs. So, decorticate posturing involves the cerebral hemispheres, while decerebrate posturing involves the brainstem.

Posturing patterns reflect where motor pathways are disrupted. In decorticate posturing, the disruption is above the red nucleus, typically involving the cerebral hemispheres or internal capsule. This causes the upper limbs to flex (often with adduction) while the legs extend. In decerebrate posturing, the injury is at or below the red nucleus in the brainstem, leading to loss of cortical inhibition on brainstem pathways and producing an overall extension of the arms and legs.

So, decorticate posturing involves the cerebral hemispheres, while decerebrate posturing involves the brainstem.