Discrepancies between standardized measures of cognitive level and Halstead-Reitan impairment indices as inferences of brain damage following head injuries

z scores for measures of intelligence, memory, educational achievement, and neuropsychological impairment were obtained for 193 patients who had sustained impacts of mechanical energy to their skulls. Two sets of normative data, adjusted for age and sex and not adjusted for these variables, were employed to compute indices of neurocognitive proficiency (the inverse of impairment). 80% or 76 of the 96 patients whose Halstead-Reitan Indices were greater than 0.4 displayed scores for neurocognitive proficiency that were two or more standard deviations below the averages of their scores for intelligence, memory, and educational achievement. None of the patents whose Impairment Indices were 0.4 or less displayed this discrepancy. There were no statistically significant differences between these two groups of patients with respect to the presence of unconsciousness following the injury or the duration of posttraumatic memory disruptions. The results indicate that quantitative scores for neuropsychological impairments are still the most accurate criteria to discern brain dysfunction within the mild to moderate range.     

Never cross the path of a traveling salesman: The neural network generation of Halstead-Reitan trail making tests

The Halstead-Reitan Trail Making Test (TMT) is one of the most widely used neuropsychological instruments for the assessment of brain damage. Despite its usefulness, however, the TMT has two major disadvantages. It has not been constructed in a principled manner that would facilitate systematic investigation, and there is no established procedure for generating equivalent, but stochastically different, test forms. The reason is that the generation of self-avoiding TMT pathways resembles the finding of near-optimal solutions to the Euclidean Traveling Salesman Problem (TSP) and constitutes a computational problem that is NP-complete. This article describes a practical approach to the problem of generating stochastically different test forms. This approach employs anelastic net neural network to generate TMT forms based on self-avoiding, near-optimal paths, and closed circuits. The usefulness and limitations of this solution are discussed briefly in relation to alternative and complementary problems and procedures.     

Utility of the concept of brain damage for the school psychologist

This paper attempts to show that the concept of brain damage has little utility for the school psychologist or educator. This argument is based on three major points: (a) the definition of brain damage, particularly minimal brain damage, is unclear and confusing; (b) diagnosis of brain damage is often difficult and results of psychological testing often equivocal; and (c) differential treatment programs and educational procedures suggested for the brain injured child appear to be of only questionable value. Extreme caution is urged to prevent hasty, uncritical adoption of many inadequately tested teaching and management techniques advocated for brain damaged children.     

Cluttering after brain damage

On the basis of published cases and of observations made in two patients, a syndrome of acquired cluttering after brain damage in adults is delineated, and a hypothesis is presented regarding the patho-physiology of the disorder.     

Stuttering following brain damage

This paper describes the neurological, language, and speech status of seven brain-damaged patients with symptoms of cortical stuttering. We compare data from our seven patients to data presented on other brain-damaged stutterers, review theories of cortical stuttering's etiology, advance alternative hypotheses about mechanisms underlying such dy sfluencies, and compare cortical stuttering to stuttering in childhood.     

Reversal operations after brain damage

The ability to perform reversals—that is, the appreciation of the relationship between original and transformed states of knowledge—is critical to human thought processes. In order to assess whether a number of “special-purpose processors” are responsible for reversal operations, depending on the particular context in which the reversal is couched, or whether a single “core processing mechanism” subserves a critical aspect of reversal operations regardless of the specific context, patients with localized brain damage were asked to solve eight reversal problems. Visual and auditory reversals mediated by linguistic and non-linguistic symbol systems were presented. The findings demonstrate that patients with insult to the anterior portion of the right hemisphere encounter more difficulty performing reversals than patients with right posterior insult, Broca's aphasics, and fluent aphasics. This is regardless of the symbol system mediating the reversal, regardless of the modality of presentation, and regardless of the amount of available processing time. Subjects with insult to the posterior region of the left hemisphere or the right hemisphere also exhibit some difficulty solving reversal problems, although their difficulties appear modality specific. These data lend support to the claim that a core processing mechanism may play a critical role in the performance of reversal operations.     

Memory strategies with brain damage

The ability of anterograde amnesics with and without a history of alcoholism and patients with frontal lobe damage to think about memory, memorizing, and remembering was assessed. Alcoholic Korsakoffs' and frontal lobe patients' knowledge and use of memory strategies was deficient when compared with controls whereas nonalcoholic amnesics' was not. The use of the categorization mnemonic was assessed in a verbal learning experiment. Frontal lobe patients failed to spontaneously categorize a categorizable word list when trying to memorize it. Nevertheless, when forced to categorize the list, they benefited from the imposed structure. Nonalcoholic amnesics spontaneously categorized the list and benefited from the resulting organization.     

Reliability of the Halstead-Reitan Battery in individuals displaying acutely psychotic behavior

The purpose of the present study is to examine the test-retest reliability of the Halstead-Reitan Battery (HRB) in an acutely psychotic population. Ten acutely psychotic patients, initially tested upon admission to an inpatient unit of the Austin State Hospital, were selected for retesting on the basis of showing the most complete remission of psychotic symptoms of all patients tested over the 14-month period from June 1978 to August 1979. Only patients showing good remission were selected in order to maximize the potential for changes in test performance to occur and, thus, provide a conservative estimate of test-retest reliability. The average retest interval was 10.4 weeks (SD=6.67), with retest being completed just prior to discharge. Reliability was examined for each HRB subtest across subjects, as well as for each subject across subtest. While the patients generally showed an improved performance at retest, the reliability of the HRB was relatively high.     

Confirmatory tests in the diagnosis of brain death: The role of the radioisotope brain scan

In recent years physicians have used a variety of laboratory studies as confirmatory tests in the diagnosis of brain death. The most widely used test has been the EEG. However, with the development of newer technologies capable of measuring other parameters of brain functions, other laboratory studies are playing an increasingly important role in confirming brain death. In this article, we discuss the role of one of these newer tests, the radioactive brain scan, and compare its advantages and limitations with the EEG.