Ralph Reitan and Biological Intelligence

Archives of Clinical Neuropsychology 30 (2015) 733– 739 Special Article Ralph Reitan and Biological Intelligence Gerald Goldstein VISN IV MIRECC, VA Pittsburgh Healthcare System, Pittsburgh, PA, USA E-mail address: . Accepted 5 October 2015 Introduction The success of Ralph Reitan’s career may be attributed to numerous influences, but here consideration will be given to the theoretical framework in which it emerged. As we know, Reitan was a student of Ward Halstead, and developed a strong interest in Halstead’s work with a group of neurosurgeons in the development of new test procedures for assessing brain function in humans. The tests described in Halstead’s Brain and Intelligence: A quantitative study of the frontal lobes (1947) and related publications (Halstead, 1951) formed the basis for Reitan’s research and clinical careers. After reviewing a large number of tests Halstead identified 26 procedures, listed in his book, as a particular group of tests he characterized as potential “quantitative indicators” of “Biological Intelligence” (Halstead, 1951), and stressed the importance of the abilities these tests assessed for adaptive functioning. A factor analysis with a four factor solution based upon several of these tests became the basis of what we now know as the Halstead-Reitan Battery. The theory developed was evolutionary or “Darwinian” in nature, and Halstead offered the view that his tests were indicators of level of adaptive function in civilized society. Based upon a survival of the fittest concept, they reflected those abilities that promoted survival on the planet. Those individuals who developed brain function that supported acquisition of these abilities were those who did not become extinct. As indicated in the title of his book, Halstead believed that this evolutionary process was largely a product of development of the frontal lobes. While the part of the theory about the frontal lobes remains unsettled (Reitan & Wolfson, 1994), there is greater agreement that Halstead’s tests are particularly sensitive to brain function unlike another group of tests characterized as measuring “psychometric intelligence” that are more related to cultural influences, notably education. Reitan continued to characterize these tests as measures of adaptive behavior. The major point developed in this presentation is that a substantial portion of Ralph Reitan’s success is that he had the wisdom to recognize that Halstead’s “Biological Intelligence” tests were very powerful instruments for assessing brain function, and that tests of that type differed from “psychometric intelligence” tests that were associated mainly with upbringing. Some of these tests had existed for many years, but they had not been related so coherently to the evolution of the brain and the emergence of adaptive behaviors. For example, a form of the Tactual Performance Test was used since the Civil War, but its relevance to brain function was not understood. Believers in natural selection would no doubt make the assumption that life forms emerged that did not acquire the abilities of the type assessed by these tests, and on the basis of natural selection did not survive. The clear clinical inference that can be made is that impairment of the brain systems that support “Biological Intelligence” because of damage or disease would be associated with loss of the associated behaviors. It was this inference that appeared to be the major impetus for Reitan’s research vision and for the development of clinical neuropsychology in general. Rather than pursuing a factor analytic model as initiated by Halstead, Reitan developed a form of levels of processing model of brain function as presented in Reitan and Wolfson (1993a, 1993b) starting with input and going to attention, concentration, and memory; then followed by a branching into language and visual spatial skills, a convergence to concept formation, reasoning and logical analysis leading to some form of output. Assessment of each of these levels is accomplished with a battery of tests the results of which produce inferences related to general level of performance, pathognomonic signs, patterns of performance, and interhemispheric differences. An important point to be made, however, is that Halstead’s and Reitan’s models used essentially the same # The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: . doi:10.1093/arclin/acv069 734 G. Goldstein / Archives of Clinical Neuropsychology 30 (2015); 733–739 data base, a battery of quantitative tests sensitive to various aspects of brain function and dysfunction. Perhaps more importantly was that the battery contained tests that were powerful indicators of brain function rather than simply relying on the pathognomonic sign approaches commonly relied upon by neurology, or single indicators of cognitive ability employed by those who base their assessments on single standard intelligence (IQ) tests. Crucial to this approach was the extensive use of procedures characterized as tests of Biological Intelligence, such as the Category or Tactual Performance Test. The complete battery after Reitan’s modifications contained tests of both biological and psychometric intelligence since their contrast is of major clinical significance. There are important differences in brain function between individuals who do poorly on Biological Intelligence tests in association with poor performance on psychometric intelligence as well, as commonly involved in individuals with intellectual disability (previously called mental retardation) and those with selective impairment on Biological Intelligence tests like the Category Test, with good preservation of psychometric intelligence, a pattern commonly associated with acquired brain dysfunction. Unlike other approaches to neuropsychological assessment, both Halstead and Reitan were committed to quantitative measures, although they used quantification in different ways. As indicated, Reitan was not a strong advocate of factor analysis, never using it in his research, and his thinking did not reflect Halstead’s factor model. One does not see in his research or clinical work analyses presented within the framework of Halstead’s factor analysis. Rather, it was based on stages of processing going from sensory-perceptual input through attention and remembering, analysis by the appropriate cerebral hemisphere and conceptual reasoning. However, the procedures used for assessment at each of these levels were quite similar, based largely on many of the tests described in Halstead’s Brain and Intelligence. Reitan therefore used the concept of Biological Intelligence in his work, but in a way quite different from that of Halstead. A major unique contribution by Reitan was that of taking the Biological Intelligence concept and building with it a major system for the study of brain function using both experimental and clinical methods. What are t (...truncated)