| This study investigated the memory and attention performance of patients with posttraumatic stress disorder (PTSD), mild traumatic brain injury (mTBI), and both diagnoses. The WAIS-III and WMS-III test scores of 217 patients seen after a motor vehicle accident (MVA) were examined and revealed no between-groups differences on memory variables. However, ANCOVAs with education as the covariate did reveal between-groups differences on 3 of the 6 attention variables (WMS-III Working Memory Index, Arithmetic, and Spatial Span), with post-hoc t-tests demonstrating that the mTBI-only group performed significantly better than both the PTSD-only and the comorbid PTSD/mTBI groups. The data were then grouped for individuals who were seen either I to 3 months, 4 to 12 months, or 13 to 36 months post-accident, to clarify how memory and attention problems related to mTBl and PTSD, both separately and combined, may change across these time frames. Factorial ANCOVAs with education as the covariate, as well as the 3 diagnostic groups and 3 timeframe groups as factors revealed no significant interaction effects and no main effects for diagnosis on either the memory or attention variables. However, several main effects for the time since MVA group were significant. Post-hoc t-tests revealed no significant differences between the 1- to 3-month group and the 4- to 12-month group, but did show significant improvement between the 4- to 12-month and 13- to 36-month timeframes on Spatial Span, Visual Immediate and Delayed, and Family Pictures I, but not on other memory or attention variables. When scores were recoded to reflect impairment "I SD below the mean) or lack of impairment, minimal differences in the percentage of impairment across diagnostic groups and time post-trauma groups were uncovered. Interestingly, educational and gender differences were evidenced. Gender differences emerged through analysis ofparticipants' qualitative data from clinical interviews. Minimal differences in the memory and attention scores among the 3 diagnostic groups reinforces the message that neuropsychologists cannot look to test data alone to clarify patients' diagnoses. These findings highlight the need for a detailed clinical interview in making a differential diagnosis for PTSD and/or mTBI.;KEY WORDS: mild traumatic brain injury, posttraumatic stress disorder, memory deficits, attention deficits, motor vehicle accidents... |
