| Recent data shows that, on average, approximately 1.4 million people sustain a traumatic brain injury (TBI) each year in the United States (Lucas & Addeo, 2006). There are certain cognitive deficits common to TBIs. These injuries typically produce deficits in attention and distractibility; slowed cognitive processing and behavioral responding; impaired learning and retrieval of new information; deficits in auditory and visual processing; and a variety of problems in executive function (Lucas & Addeo, 2006). This study proposed to examine the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) because of its widespread use in standard neuropsychological evaluations. Data was collected from a sample of 33 participants from the Pasadena Rehabilitation Institute (PRI), referred by neurologists for psychological testing following suspected TBI. Although the results of the study suggested that there were no significant differences between the study variables and the control group, they were consistent with respect to the pattern of index scores from previously described research suggesting that PSI and WMI are most sensitive to brain injury (Lezak et al., 2004). In addition to the WAIS-IV variables, two measurements of effort (b and Dot Test) were used (1) to assess for probability that the results could be considered valid and reliable and (2) to include b and Dot Test performances in a sample of TBI to the existing database on these effort tests. The results from both effort measures suggested that the participants exerted strong effort during the testing and more often than not displayed credible cognitive symptoms. |
