om some deficits. They have some trouble with spoken commands and learning new skills. Their recent memory is poor, as is their topographic memory and new verbal memory. Because of the memory deficits, they don't tend to read, watch TV or watch movies. These patients also do not dream, and have blunted emotional responses. Many report having little control over their left hand.
21.4 The lumbar puncture is usually done above or below the fourth lumbar vertebra (Applegate, 2000, 170). This is the site of choice because the spinal cord ends at the fist lumbar vertebra, and entering the subarachnoid space above or below the fourth lumbar vertebra ensures that there is no risk of damaging the spinal cord with the needle.
21.5 There are two enlargements of the spinal cord, one in the cervical region and one in the lumbar region (Applegate, 2000, 170). The enlargement in the cervical region gives rise to the nerves which supply the upper extremities, and the enlargement in the lumbar region gives rise to the nerves that supply the lower extremities.
21.6 In the cerebral hemispheres, the white matter forms the bulk of the tissue, and is covered by a thin layer of gray matter (Applegate, 2000, 164). In the spinal cord, the grey matter forms the central core and is covered by white matter (Applegate, 20000, 171).
21.8 Upper motor neurons carry information from the brain to the spinal cord, where they synapse with lower motor neurons (Reyerse, 2004). The lower motor neurons innervate muscles directly. Damage to upper motor neurons will cause muscle weakness without atrophy; damage to lower motor neurons will cause muscle weakness, atrophy, flaccidity, and there will be no reflex response.
21.9 If the lower motor neurons serving a muscle has been destroyed it will not contract because the lower motor neurons directly innervate the muscles (Reyerse, 2004). If the nerves are destroyed, the muscle is no longer inner...