Daniel Allen

A comparison was made among participants with schizophrenia and those with structural lateralized or diffuse brain damage in order to determine the extent to which the cognitive profile of the schizophrenia sample resembled the profiles obtained from patients with left-hemisphere, right-hemisphere, and diffuse brain damage. The Halstead-Reitan Neuropsychological Battery was used as the testing procedure. The data were subjected to discriminant analysis in order to obtain frequencies of predicted classification of the participants with schizophrenia into schizophrenia, left-hemisphere, right-hemisphere, and diffuse groups. Half of the participants with schizophrenia were classified into the schizophrenia group. The other half was evenly distributed across the left-hemisphere, right-hemisphere, and diffuse brain damage groups. There was not a disproportionately large number of participants classified into the left-hemisphere group. Comparisons among these four predicted groups were ac...

The authors' goal was to determine whether cognitively impaired patients with schizophrenia exhibit age-related cognitive declines similar to those of patients with schizophrenia who do not have substantial cognitive impairment. Correlation coefficients were computed between age and the Average Impairment Rating, a summary index of cognitive ability, in a group of 77 patients with schizophrenia. These patients were clustered into two groups: one with near-normal cognitive function (N=51) and one with severely impaired cognitive function (N=26). A group of patients with senile dementia (N=21) and another comparison group of nonschizophrenic patients (N=299) were used as reference groups. There were significant correlations between age and the Average Impairment Rating in all groups except the cognitively impaired patients with schizophrenia, in which a zero-order correlation was obtained. Patients with schizophrenia who have substantial cognitive impairment do not have the signif...

Intelligence tests are commonly administered to children following moderate-to-severe traumatic brain injury (TBI). The Reynolds Intellectual Assessment Scales (RIAS) is a recently developed measure of intellectual ability that has a number of appealing features for assessing individuals with brain damage, but as yet has little validity information when applied to children with TBI or other forms of brain injury. It is therefore unclear whether RIAS scores are sensitive to brain injury and how they compare to older more well-established tests such as the Wechsler scales. The current article reports two studies that examine these matters in youth with TBI. The first study examined sensitivity of the RIAS to TBI in 110 children. Results indicated the TBI sample performed significantly worse compared with the standardization sample on all RIAS index scores. The second study included 102 children who were administered either the RIAS, Wechsler Intelligence Scale for Children-Third Editi...

Traumatic brain injury (TBI) may have a profound impact on a child's ongoing development. Various risk factors have been found to predict outcome, but considerable variability remains unexplained. This study used a prospective, longitudinal design to examine recovery of memory function following TBI within the pre school period. Ninety-six children with TBI were divided according to injury severity (mild, moderate, severe), and compared to age and SES matched healthy controls (n = 35). Children were evaluated acutely and at 6,12 and 18 months post-injury using intellectual and memory measures. Results showed a relationship between greater injury severity and poorer intellectual ability. This dose-response relationship was not clearly evident for memory function within the acute phase of recovery, but developed over time, with greater memory impairments evident for children with more severe TBI by 12 months post-injury. Children with mild TBI exhibited few memory problems. Findings are discussed in the context of theories of plasticity and recovery of function.

Recent factor-analytic studies of the Halstead Category Test (HCT) indicate that its seven subtests form three factors including a Counting factor (subtests I and II), a Spatial Positional Reasoning factor (subtests III, IV, and VII), and a Proportional Reasoning factor (subtests V, VI, and VII). The sensitivity and specificity of these factors to heterogeneous forms of brain damage was examined in a large sample of patients and a normal comparison sample. A prorated Impairment Index, which excluded the HCT error score, was used to assign participants with brain damage into mild, moderate, and severe impairment groups. Also, groups with various forms of neuropathology were contrasted. Results indicated that both the Spatial Positional Reasoning and the Proportional Reasoning factors were sensitive to brain damage. However, in all of the brain-damage groups, a greater percentage of errors were made on the Spatial Positional factor, suggesting that of the two it was more difficult for those with brain damage. The sensitivity and specificity of the Spatial Positional factor score for detection of brain damage was comparable to that of the total error score, which has been previously demonstrated to be an excellent indicator of brain damage. Findings provide further support for the validity of the HCT factors, and are consistent with the view that factor scores may be useful in interpreting the HCT.