A controlled study of neuropsychological deficits in acute spinal cord injury patients

Abstract

According to a number of studies, between 40% and 60% of acute traumatic spinal cord injury (SCI) patients demonstrate cognitive dysfunction resulting from various forms of cerebral damage, including concurrent or premorbid closed head injury, chronic alcohol or substance abuse, and other causes. However, applicability of findings from these reports has been limited due to the use of inadequate neuropsychological testing techniques and the lack of control data. In a collaborative investigation, 81 acute SCI patients and 61 non-injured control subjects between 18 and 55 years of age completed a comprehensive motor-free neuropsychological test battery, including: Halstead Category Test (HCT), Vocabulary Subtest (VOCAB) of the Wechsler Adult Intelligence Scale - Revised; Mental Control (MC) Subtest, and Initial and Recall trials of Logical Memory (LM) and Paired Associates (PA) Subtests of the Wechsler Memory Scale; and the 8 trials of the Rey Auditory Verbal Learning Test (RAVLT). Percentages of retained information on the LM and PA were also calculated. Impairment levels for each test were defined as values which exceeded two standard deviations (one-tailed) from the control mean. Based on this definition, the prevalence of neuropsychological abnormality on each test ranged between 10% and 40%. Mean performance levels of patients were significantly more impaired than those of control subjects for all tests except for the Interference trial of the RAVLT and for the percentages of retained information on the LM and PA subtests. Comparison of test results of SCI patients with those of control subjects demonstrates that poor attention span and limited initial learning ability are frequent problems among SCI patients. Other common neuropsychological deficits among these patients include poor concentration ability, impaired memory function, and altered problem solving ability. These deficits may interfere with rehabilitation following SCI.