1. From the Stroke Rehabilitation Program, Braintree Hospital Rehabilitation Network, Braintree, MA, and Department of Neurology, Boston University School of Medicine, Boston, MA.
2. Supported in part by Memory Disorders Research Center at Boston University grant NS 26985.
3. Presented in part at the Academy of Aphasia, Cambridge, MA, October, 1993.
4. Received November 14, 1995. Accepted in final form June 17, 1996.
5. Address correspondence and reprint requests to Dr. Michael P. Alexander, c/o Aphasia Research Center, Boston VAMC, 150 South Huntington Ave, Boston, MA 02130.