Procedural memory during posttraumatic amnesia in survivors of severe closed head injury. Implications for rehabilitation
J. Ewert, H. S. Levin, M. G. Watson and Z. Kalisky
Department of Psychology, University of Houston, TX.
To investigate the possibility that learning of skills (ie, procedural
memory) is preserved during posttraumatic amnesia, 16 amnesic survivors of
severe closed head injury and 16 control subjects were studied. Procedural
learning tasks included mirror reading, mazes, and a pursuit rotor task
that involved tracking a rotating target. Declarative memory was assessed
by testing recognition of the words used in mirror reading and a
questionnaire concerning details of the previous testing session. Learning
was evaluated on 3 consecutive days and a fourth session was scheduled
after resolution of posttraumatic amnesia. Despite stable impairment of
declarative memory during posttraumatic amnesia, the performance of
head-injured patients improved across sessions on all procedural tasks and
showed transfer to testing after resolution of posttraumatic amnesia.
