Damage to the Postcentral Gyrus of the parietal lobe, the dorsal columns, or the dorsal root ganglion may produce a loss of proprioception, astereognosis (ability to recognize object in ones hand), loss of vibratory sense, and loss of two-point discrimination in the trunk or extremities. In general, describe the side of the body involved when damage occurs in the following areas, and explain your rationale.
- Dorsal columns below the medulla
- - the loss in proprioception is on the same side of the injury. The nerve has not decussated yet (ipsilateral)
- Dorsal columns above the medulla
- - The loss in proprioception is on the contralateral side of the injury because the nerve has decussated or crossed the midline (contralateral)