Ralph M. Reitan's passing on August 24, 2014 washed as a tsunami of great sadness over the many clinical neuropsychologists who knew Reitan, and for the field generally. Ralph was the anchor of empiricism and evidence-based practice in clinical neuropsychology, who developed and vigorously promoted neuropsychology as an evidence-based specialty long before the term was so popular. Reitan is best known for his development of the various age levels of the Halstead-Reitan Neuropsychological Test Battery (HRNTB) for clinical applications to the assessment and treatment of brain-damaged individuals. As is well known, the core tests of the HRNTB were initially developed by Reitan's primary mentor, Ward Halstead, as part of a research program on biological intelligence, but Reitan, over many decades, adapted, and augmented the original core battery for clinical application in the assessment and treatment of brain-damaged individuals. Reitan's initial research approach was to compare control subjects to previously diagnosed persons known to have heterogeneous types of lesions in various locations and identify the procedures that were sensitive to the general condition of the brain. Essentially, the HRNTB was developed to be sensitive to neurological as opposed to behavioral variables as a critical concern for clinical neuropsychologists was the biological condition of the human brain. Reitan used empirical methods to determine and demonstrate that performances on specific psychological tests (HRNTB) were brain related rather than behavior related. In a research career of over 60 years, Reitan published numerous scientific peer-reviewed articles, book chapters, and books demonstrating the validity of the interpretations he proffered for the various score patterns on the HRNTB in the clinical assessment of brain-damaged individuals while working at major research universities including Indiana University, University of Washington, and the University of Arizona. Reitan published numerous peer-reviewed papers from 1948 (Aita & Reitan, 1948) to 2008 (Reitan & Wolfson, 2008), a 60-year span of impressive scholarship. Numerous other research studies have since cross-validated Reitan's research findings in the USA and in other countries around the world (Hevern, 1980; Horton, 1997, 2008).
Perhaps less understood and less appreciated was the impact of Reitan's research and innovative clinical procedures in establishing the role of the clinical neuropsychologist in the healthcare system, particularly in hospital and medical school practice and curriculum. When Reitan began his research program at Indiana University, psychologists were not typically included as clinicians in departments of neurology. Reitan's research was of such a high level that neurologists and other physicians had to accept the fact that clinical neuropsychologists had important contributions to make in terms of the assessment and treatment of brain-damaged individuals. Clinical neuropsychologists who entered the field in this century, many times are unaware that in the last century, the clinical role of the neuropsychologist had to be carved out of an initially unwelcoming healthcare system. Reitan through his research and clinical work with brain-damaged individuals clearly demonstrated the important contributions that clinical neuropsychologists make to the assessment and treatment of brain-damaged individuals. In a time where X-ray was nearly the only imaging procedure available and localization of brain functions was crude at best, Reitan travelled the lecture circuit demonstrating the value of neuropsychological test data in localization and diagnosis of central nervous system issues and often contributed to the surgical interventions required by providing surgeons with information on brain functions in the individual patient not otherwise available. Reitan's impact is difficult to overstate as his research was the major reason that departments of neurology decided to include neuropsychologists as clinical staff members. Every clinical neuropsychologist working today owes a debt to Reitan's contributions.
It might also be noted that in addition to these outstanding clinical neuropsychology research contributions, Reitan was an extremely erudite and kind individual who spent numerous hours teaching and supervising graduate students, interns, and postdoctoral students. He was extremely generous in sharing his research findings and clinical wisdom, and the majority of leaders in clinical neuropsychology in the last century had been either students of Reitan or students of his students.
Reitan was truly the Father of American Clinical Neuropsychology, and the great importance of his many contributions will always be remembered.
Reitan was born in the place that translated from Norwegian as “Sweet Meadow” in South Dakota. He was a son of a Lutheran minister and spent much of his early life traveling from one parsonage to another in the Midwest. Unfortunately, Reitan's family was quite poor, and he had to go to school with newspapers stuffed in his shoes because the shoes had holes in them, and his family was too poor to buy new shoes. Interestingly, Reitan did not speak English until he went to elementary school because his first language was Norwegian as many of the Lutheran communities in the Midwest where his father served as a minister only spoke Norwegian. So the father of American neuropsychology was a speaker of English as a second language.
Elementary school was not a pleasant experience for Reitan as he rather famously punched his fifth grade teacher because the teacher tried to make him go to the blackboard to do fractions. Reitan noted no teachers bothered him after that. He did retain his feistiness throughout his career, and it served him well in the early days of establishing clinical neuropsychology as a contributing field to patient care.
Also in high school, Reitan could not run for the Presidency of the Senior Class because of his parents' religious beliefs. His minister father forbade dancing, singing, drinking alcohol, or going to movies. In Reitan's high school, the tradition was the senior class president danced the first dance at the senior prom. As Reitan could not dance, he could not run to be the senior class president and instead served as the vice-president of the high school senior class. Regarding movies, Reitan noted his parents did exempt from the ban those movies that were documentaries because of their educational value, so Reitan smilingly noted he saw many documentaries in his high school years.
Reitan also during his teenage years in Chicago was a member of a street gang. Apparently at that time in order to settle disputes between street gangs, each gang would designate one of their members to fight a designated member of the other street gang. Reitan's street gang earned great distinction because Reitan was actually a relatively small individual but surprisingly potent as a fighter. It is noteworthy that Reitan was the 137 pound Golden Gloves boxing champion of the city of Chicago in the early 1940s. Remarkably at this time, Reitan was rated 4F for military service during World War II because of a shoulder injury. He later described this as a major turning point in his life believing that if he had been drafted into the military in WWII in all likelihood he would have been a second lieutenant who died in a beach landing. When talking about this, Reitan always appeared very sad reflecting on his peers who died and the chance circumstances that allowed him to live.
After obtaining an undergraduate degree in psychology from the 39th Street YMCA in the city of Chicago, Reitan attained a position as a psychologist in an Army hospital in the Chicago area. Reitan had a physician as a patient who had a profound effect on him. The physician apparently had had a stroke and had recovered, but the physician told Reitan that he (the physician) could no longer care for his patients as he used to prior to the stroke and asked Reitan for help. Reitan administered to the physician all of the available psychological tests of the day (this was the 1940s) and found the physician to have scored above the 85th percentile on all of the psychological tests. This case profoundly influenced Reitan in the direction of studying brain injury. Apparently at the time Reitan was working at the Army Hospital, he was saving money with the intention of going to study counseling and psychotherapy with Carl Rogers at the Ohio State University (many individuals who worked with Reitan found the idea of Reitan as a Rogerian client centered nondirective therapist very funny as Reitan could be rather firm in his views). At the same time, it must be said, all kidding aside, anyone who consulted Reitan about a personal problem found that he would demonstrate unconditional positive regard, accurate empathy, and kindness in response to personal confidences—he was a psychologist of great clinical skill and also a compassionate human being. Only when Reitan felt, he was being attacked did his very firm side appear. In all likelihood he would have been a superb psychotherapist.
Nonetheless, because of his physician patient who had had a stroke and self-reported he (the physician) was unable to take care of his patients as before the stroke but scored well on all of the psychological tests of the day, Reitan began to investigate the question of brain damage effects and was told of the research program on biological intelligence begun by Ward Halstead at the University of Chicago Medical School. Reitan visited Halstead and was greatly impressed by his research program. Halstead in turn was impressed by Reitan (Reitan as a young man could exceed 70 taps in 10 s on the Finger Tapping Test, like a machine, which is an outstanding score) and invited Reitan to study with him (Halstead). Reitan still had to be accepted in the psychology program at the University of Chicago but had a very positive interview with professor Thurstone, a famous statistician, and was accepted as a doctoral student in the psychology department. Reitan noted that his language facility in Norwegian was a major factor in gaining rapport with professor Thurstone who was and spoke Swedish and the two were able to communicate in their respective non-English languages. Thurstone took an important interest in Reitan and spent many hours teaching Reitan statistics.
It is interesting that despite Reitan's difficulties with mathematics in elementary school, he did very well with respect to statistics and quantitative reasoning, the point being that Reitan became renowned for the methodological rigor of his research studies and statistical acumen. A Deputy Director of the National Institute of Neurological Disorders and Stroke (NINDS) at the National Institutes of Health (NIH) once endorsed the results of a research study on Epilepsy by simply saying “The study was designed by Ralph M. Reitan.,” The level of respect his work engendered was very clear.
An interesting side light was that Reitan because of poverty had to work two full time jobs at a time while going to the University of Chicago full time throughout graduate school. One of his positions was at a large bank in Chicago. The bank executives decided to put up a suggestion box for employees to submit suggestions on how to improve the bank operations and efficiency and hired Reitan, the poor graduate student, to do research studies to evaluate the worth of the suggestions. This was apparently an excellent job for a young psychologist. Unfortunately, few suggestions were submitted, and Reitan was concerned he might be let go. With amazing daring, Reitan started submitting suggestions to the suggestion box himself. Also, Reitan was a member of the bank's committee that reviewed the written suggestions and assessed the need for Reitan to design and carry out a research study to evaluate them. Having devised and submitted the suggestions made it easier for Reitan to advocate for them. After Reitan, then in his 80s told this story to an incredulous group at dinner, he was asked what would have happened if the bank executive had found out Reitan was the person submitting the suggestions. Reitan's facial expression and mood immediately changed to concern. Indeed, he went from being the gentle kind full professor to the 12-year-old boy caught with his hand in the cookie jar in demeanor, and he said in a very dramatic tone “They would have fired me at once!” Anyone who had been a poor graduate student, being cold because of inadequate clothing, not sure of being able to buy enough food to eat in the next week, not to mention paying tuition, would have a great deal of empathy for Reitan's situation and as George Simeon said “understand and do not judge.”
Another important influence on Reitan in graduate school at the University of Chicago was Samuel Beck and Beck's method of blind interpretation of Rorschach responses. Later Reitan would do blind interpretations of neuropsychological test data from the HRNTB to demonstrate that information in the neuropsychological test scores was the basis for the interpretations rather than observations of the patient or the patient's clinical history. This method was used primarily as a research device to demonstrate that the neuropsychological test scores were predictive of brain behavior relationships such as degree of brain damage, laterality, and localization. It might be also noted that Reitan was required by Halstead to take the first 2 years of medical school (including cutting up his own cadaver) as part of his doctoral program in psychology so that Reitan would be on a par with physicians when discussing anatomy, physiology, and pathology.
In order to provide a perspective on Reitan's important contributions to clinical neuropsychology, it will be necessary to start with a discussion of the concept of intelligence which was very central to understanding the concept of “Biological Intelligence” which was the focus of Halstead's research and later a focus of Reitan's research. The discussion will be at some length because conceptually intelligence is the foundation of psychological assessment. Also, the concept of biological intelligence is best described and understood in counterpoint to the assessment of intelligence. The field of clinical neuropsychology is composed of those human mental abilities that are to some extent distinct from intelligence. There is of course a degree of overlap but there is also a degree of divergence. Moreover, clinical neuropsychological assessment is to a large degree based on early work on biological intelligence and how biological intelligence diverged from the concept of intelligence.
While the psychological construct of intelligence has been of major importance to society, it nonetheless has limitations with respect to characterizing human mental abilities. Halstead (1947) observed that in many cases brain injury patients were still able to score well on intelligence tests despite clear and substantial brain damage and significant adaptive behavior problems in daily living. Halstead (1947) concluded that there was an additional brain-based latent construct that was sensitive to human adaptive abilities but poorly evaluated by then existing intelligence tests. Theoretical interest in the human mental abilities subserved by an intact human brain was the focus of an important research program (Halstead, 1947) that was pivotal to the development of the field of clinical neuropsychology. Halstead also conceptualized a type of mental abilities that was different from what was measured by the then standard psychometric intelligence tests; he named this type of mental ability “Biological Intelligence” (Halstead, 1947). Essentially Halstead (1947) postulated that there were human adaptive abilities subserved by an intact uninjured human brain that went beyond those measured by the then standard intelligence tests. In other words these human adaptive abilities that were subserved by an intact uninjured human brain were described as “Biological Intelligence.”
Intelligence has been conceptualized as a product of the overall physiological efficiency of the brain. Wechsler (1944) suggested that intelligence could be defined as “the aggregate or global capacity of the individual to act purposefully, to think rationally, and to deal effectively with his environment” (p. 3). Intelligence is a major psychological construct that includes theoretical, social, and clinical perspectives. Human intelligence has served as a selection and placement criterion as well as an aid in diagnosis and treatment, including as a baseline of overall mental function against which more specific cognitive skills may be compared. Halstead (1947) found then contemporary intelligence tests inadequate to satisfy Wechsler's definition (1944) of intelligence and sought to identify the brain-based latent construct of biological intelligence that would better satisfy Wechsler's definition.
Halstead established an experimental brain–behavior research program at the University of Chicago Medical School focused on mental abilities in the intact human brain which he described and conceptualized as biological intelligence (Horton & Wedding, 1984). Halstead studied the behavioral deficits of brain injured persons which were distinct from psychometric intelligence so he could identify human mental abilities important for adaptive functioning and problem solving. Halstead (1947) further postulated biological intelligence resided in the frontal lobes, but that notion was disproven by later research. To a degree, the current unanswered questions in clinical neuropsychology regarding executive functioning in the human brain might be seen as an extension of the search for biological intelligence. In many ways, Halstead's research has implications that continue.
In the course of his research, Halstead first observed brain injured individuals in naturalistic settings to gain insight into their neuropsychological deficits and later developed and assessed with psychological tests which were intended to significantly differentiate between individuals with documented brain injuries and individuals with no documented history of brain injury (Halstead, 1947). These tests, as they were found to be uniquely sensitive to the adaptive functioning of neurological patients, were then termed neuropsychological tests. In other words, the field of neuropsychology was based on development of tests that were more sensitive to intact brain functioning than intelligence tests. Halstead had defined intelligence operationally as what intelligence tests measured, so his tests were designed to measure human adaptive abilities that were not captured by intelligence tests. As earlier noted, many individuals with documented brain injuries did not demonstrate deficits on intelligence tests and the lack of clear deficits in intelligence suggested that, in individuals with documented brain injuries and adaptive functioning deficits, there had to be abilities that intelligence tests were not measuring. Halstead's tests were clearly better able to differentiate brain damaged from normal subjects than intelligence tests alone and thereby validated the notion of unique human brain-based adaptive functioning and problem-solving abilities.
Reitan became very interested in the concept of biological intelligence for both research and clinical purposes (Horton & Wedding, 1984). In many ways, the physician patient of Reitan's who had a stroke but scored above the 85th percentile on all of the available psychological tests of the day was a classic example of the puzzle of the adaptive ability deficits caused by a brain injury.
Reitan's Early Career
When Reitan graduated from the University of Chicago and went to Indiana University Medical School, he established his own neuropsychology laboratory for two purposes—first to validate Halstead's tests as measures of biological intelligence, which was postulated to reside in the frontal lobes, and secondly to validate a clinical neuropsychological test battery based on Halstead's tests as a core assessment of the behavioral problems of neurological patients and aid in treating these patients (Reitan, 1974). It might be noted that when Reitan established his neuropsychology laboratory there were relatively few psychologists working in medical centers and probably less than a handful working in departments of neurology. At the University of Iowa Medical Center, Department of Neurology, around the same time, Arthur Benton (Benton, 1974), another important early clinical neuropsychology contributor, was given a former coat closet in which to conduct neuropsychological assessments of neurological patients.
In addition, from an historical note, in the 1950s there were no CT or MRI brain scans, only flat film X-ray and pneumoencephalography. An early selling point for clinical neuropsychological assessment for neurology patients at that time was that neuropsychological assessment was a non-invasive behavioral procedure. One of the neurological diagnostic assessment procedures used at that time was pneumoencephalography, which required the patient to be put on a tilt table, have the patient's head lowered and his legs raised and air forced into the ventricles of the brain. The neurodiagnostic procedure often caused the patient severe headaches and as many as 10% of the patients would die. While this seems to have been barbaric, at the time it was a standard diagnostic procedure in neurology.
Reitan's work in augmenting Halstead's tests to develop a clinical neuropsychology test battery was seen as a much safer way to assess neurological patients. An interesting fact is that Reitan had great success in obtaining grant funding for his research. Also, Reitan extensively used neuropsychology technicians to administer the HRNTB to patients. This enabled him to do blind interpretations of the neuropsychological test data. Another point was that Reitan hired the wives of neurology and neurosurgical residents to work as neuropsychology technicians. These neuropsychology technician positions were located in the medical school and were well paid with excellent working conditions and enabled the wives to support their husband throughout the husband's residency. Reitan noted that he never had a dearth of clinical referrals from the neurology and neurosurgical residents who had wives working in Reitan's neuropsychology laboratory. As should be very clear, Reitan was a very shrewd judge of human behavior and clearly understood the principle of positive reinforcement.
Thus, Reitan set up his neuropsychology laboratory to assess brain injuries. The implication of using the term “laboratory” was that, just as medical laboratories would do tests of blood and urine to produce results such as white blood cell count and thyroid levels, so the neuropsychology laboratory would do tests to determine brain–behavior relationships. In other words, a consulting relationship to the neurologists and neurosurgeons was established in terms they understood, not taking over their clinical role but providing information to enable them to function more effectively.
Halstead-Reitan Neuropsychological Test Battery
Reitan performed neuropsychological assessments over many years and accumulated large numbers of patient records of the neuropsychological tests results and also clinical neurological patient diagnostic information on each patient. When the subject numbers became large enough, Reitan started to compose groups of subjects into groups with no confirmed evidence of brain damage and groups of patients with confirmed brain damage. Reitan did blind reports and he later correlated his blind test results with the documented clinical neurological case records. Through this process of feedback, Reitan started the process of modifying and adding to his battery of neuropsychological tests. If he consistently missed diagnosing an area of the brain, then Reitan added test procedures to improve the test battery and then evaluated if the added procedures were effective in improving his diagnostic efficiency. This of course went on for many years.
As Reitan (1974) described the research process:
Specifically, an experiment was performed for every subject which consisted of (a) an intensive study of the test results (dependent variables) for each individual subject followed by (b) a written evaluation of these results (a set of predictions of neurological variables based on behavioral measurements), and finally (c) an actual comparison of these predictions with the independently obtained neurological criterion information” (p.31).
One of the first studies to emerge from Reitan's neuropsychology laboratory (Reitan, 1964a, 1964b) demonstrated the limitations of Halstead's conceptualization of biological intelligence as a frontal lobe measure. Essentially, Reitan assembled equal groups of documented brain damaged patients with brain lesions in the four quadrants of the brain, based on hard neurological criteria. The four quadrants were the left anterior and right anterior and the left and right posterior areas.
There were 16 brain-damaged subjects in each quadrant group and the results of Reitan's blind clinical interpretation correctly classified 9/16 in the left anterior quadrant, 7/16 in the right anterior quadrant, 11/16 in the left posterior quadrant and 15/16 in the right posterior quadrant (Reitan, 19647). Simply put, Reitan demonstrated that the HRNTB was most successful in assessing the right posterior quadrant and less successful in assessing the right anterior quadrant. Similarly for both the left and right anterior quadrants, the results were less successful than the left and right posterior quadrants. If Halstead's conceptualization of biological intelligence had been correct, then the most successful classification should have been in the anterior quadrants. At the same time, the HRNTB test results blindly interpreted by Reitan clearly were able to localize brain damage in human subjects.
Reitan (Reitan & Wolfson, 1986) learned a great deal regarding the assessment of neurological patients through his clinical work. As Reitan noted:
Using this procedure, we have learned that certain variables contribute little to neurological conclusions (even though they may serve as comparison variables in certain respects), whereas other combinations of test results are of unequivocal significance. This procedure has permitted us to gradually refine clinical interpretation of results on individual subjects to a high degree of accuracy, as will be illustrated later. Certain neuropsychological test data are particularly helpful in determining whether brain damage is present; other test results are especially useful for lateralizing and localizing of cerebral damage; certain patterns of results relate to generalized or diffuse cerebral damage; other test results, particularly as they reflect the entire configuration of data, are used to differentiate the chronic, static lesion from the recent acutely destructible or rapidly progressively lesion; and still different findings aid the interpreter in deciding whether the cerebral damage was sustained during the developmental years or adulthood. One can readily see that in addition to formal, controlled research studies (the type usually published in the literature) there are challenging tasks that involve development of valid clinical interpretation of results for individual subjects. Achieving this aim has required development of a test battery that represented at least a reasonable approximation of the behavioral correlates of brain function. (p.136)
While a detailed description of the HRNTB is beyond the scope of this manuscript as there have been excellent prior descriptions published (Reitan & Wolfson, 1986; Horton, 2008), a brief description by Reitan and Wolfson (1986) is offered for those unfamiliar with the cited references.
The battery consists of tests in five categories: (1) input measures; (2) test of verbal abilities; (3) measures of spatial, sequential, and manipulatory abilities; (4) tests of abstraction, reasoning, logical analysis, and concept formation; and (5) output measures. The tests cover a broad range of difficulty: both very simple and quite complex tasks are included. Attention, concentration, and memory are distributed throughout the tests in the battery, just as they appear to occur in the tasks that people face everyday living. Many of the tests require immediate problem-solving capabilities, others depend on stored information, and some require simple perceptual skills that focus principally upon the sensory modalities of vision, hearing, and touch (pp. 136–137).
Neuropsychological testing requires the assessment of multiple neuropsychological domains under a condition of maximum effort by the examinee if brain functions are to be assessed accurately. By definition, neuropsychological tests have been determined by research to be uniquely sensitive to brain damage. Perhaps Reitan's most important methodological contribution to clinical neuropsychological assessment was his conceptualization of the need to use multiple levels of inference in interpreting neuropsychological test data (Meier, 1974) along with his insistence on empirical verification. As postulated by Reitan (1974), there were four levels of inference. These are as follows: levels of performance, pathognomic signs, patterns of performance, and left right comparisons of the two sides of the body. Levels of performance are variables such as intelligence or memory and the severity of impairment. Patterns of performance are discrepancies among abilities that are not found in normal subjects. Pathognomic signs are uniquely poor performances in selected areas such as repeating a word, phrase, or short sentence, simple reading or math, drawing simple shapes, or visual field cuts. Left–right comparisons of the two sides of the body are discrepancies in motor speed or strength or visual, auditory, or simple and complex tactual perception. For motor speed or strength, a particular difference between the dominant and non-dominant upper extremity is a biological variable as invariant as having two eyes, two arms, or ten fingers. It has been demonstrated in research that the most accurate level of discriminating brain damaged from normal subjects was achieved by using all four levels of inference together. Using only a single method of inference such as level of performance yielded a lower level of accuracy.
For example, a very intelligent individual could sustain a brain injury but not suffer a significant drop in level of intelligence but might demonstrate pathognomic deficits, unusual patterns of performance, or discrepancies in performance on tasks subserved primarily by different sides of the brain. Indeed, a major reason clinical neuropsychological assessment was developed was the fact that many brain injured patients had deficits in complex activities of daily living but no or minimal loss in intelligence test performance.
Reitan and Wolfson (1986) described how the multiple methods of inference were used in clinical interpretation of neuropsychological test data.
First, it is necessary to determine how well the subject performs on each of the measures included in the battery. This approach essentially refers to level of performance and, on most of the measures, is represented by a normal distribution for non-brain damaged subjects. Since some persons perform quite well and others performed more poorly, it clearly would not be possible to accept a level-of- performance strategy alone as a basis for diagnosing cerebral damage. In other words, there are some persons who demonstrate above-average ability levels in spite of having sustained cerebral damage and some individuals with below-average ability levels who do not have cerebral damage. A level-of-performance approach represents an interindividual inferential model. It is useful for comparing subjects, but offers relatively little direct information regarding the brain functions of the individual subject. (As the reader has probably noted, this is the model most used in research studies.)
A second approach, introduced by Babcock (1930), postulated that differences in levels of performance on various tests might denote impaired brain functions, or at least a loss of efficiency in psychological performances. This approach has also been used to compute the Deterioration Quotient, based on comparison of scores from different subtests of the Wechsler Scale (Wechsler, 1955). This method represents an intraindividual comparison procedure (a comparison of the subject's own performances on various tests) and helps identify the uniqueness of an individual's ability structure. Research with the tests included in the Halstead-Reitan Battery has produced a number of intraindividual patterns that are quite useful for assessing differential functions of the brain and identifying impaired areas within the brain.
A third approach incorporated into the Halstead-Reitan Battery is the identification of specific deficits on simple tasks of the type that occur almost exclusively among brain-damaged persons. Deficits on these simple tasks may not only identify the presence of cerebral damage but also indicate areas of maximum involvement (Wheeler & Reitan, 1962). The reader should beware, however, that this inferential strategy fails to identify a significant portion of brain-damaged persons who do not show the specific deficit in question (false negatives). The fourth measurement strategy used in the Halstead-Reitan Battery to identify cerebral damage is one which compares motor and sensory-perceptual performances of the same type on the two sides of the body, thus permitting inferences regarding the functional status of homologous areas of the two cerebral hemispheres. This method is also based on intraindividual comparisons, using the subject as his or her own control. When positive findings occur they may have unequivocal significance for cerebral damage (pp. 138–139).
Essentially, Reitan conceptualized brain damage as requiring multiple methods of inference for an accurate assessment of the status of the brain. Reitan would consider level of intelligence like height as a normally (approximately) distributed variable in normal non-brain damaged individuals. On the other hand, neuropsychological impairment in brain damaged individuals is a variable that is usually skewed rather than approaching a normal distribution. That is to say, a brain injured population is expected have many individuals in the lower ranges as they have greater levels of neuropsychological impairment. Regarding pathognomic signs, it was earlier mentioned Reitan had a difficulty with arithmetic in elementary school, and it might be noted that Reitan had averred in public presentations that he could only tell the difference between his left and right hands when he assumed his boxing stance. That might be interpreted as a left/right orientation problem—and as a pathognomic sign. We do now know that boxing is not good for brains.
Fixed vs. Flexible Neuropsychology Batteries
A point might be raised regarding what had been purported to be Reitan's views regarding fixed versus flexible neuropsychological test batteries. While some have asserted that Reitan was inflexible regarding use of the entire HRNTB for every patient, that was not so. In personal communication, Reitan indicated that he appreciated that some neurological patients would be too impaired to complete an entire HRNTB. Indeed, Reitan told a story of the very impaired neurological patient who had been referred to him for neuropsychological assessment. Only the Reitan-Indiana Aphasia Screening Test could be administered to the impaired neurological patient, and Reitan provided a qualitative interpretation (similar to the approach advocated by Edith Kaplan) to the neurologist who apparently was greatly impressed by Reitan, and Reitan noted with a smile that he was very proud of that qualitative interpretation.
Reitan also noted that he had actually no problems with adding additional psychological and neuropsychological tests to the HRNTB test results, such as the Wechsler Memory Scale among others. Rather Reitan's view with regard to the HRNTB as a fixed neuropsychological test battery was that he devoted decades of his life in terms of researching what appeared to be the best and most appropriate battery of neuropsychological tests for assessing heterogeneous brain damage. If there was a better set of neuropsychological test procedures, then there should be research data demonstrating that fact. In the absence of research data, he thought it would be premature to draw conclusions using that alternative battery. Reitan was firm on the need for empirical verification, and many flexible battery approaches lack such necessary validation work.
Reitan was well aware of the fact that in many cases it would not be possible to administer a complete HRNTB, and he developed and researched a number of screening procedures to determine if a complete HRNTB should be administered (Reitan, 1958; Reitan & Wolfson, 2004). In some cases, it might be noted that times have changed. When Reitan established his neuropsychological test battery, the healthcare system was focused on producing optimal results. In the present-day, the healthcare system appears to be focused on cost containment rather than quality of services (Cummings, 1986).
In closing, it is noted that the field of clinical neuropsychology grew rapidly because of the empirical research foundation of Ralph M. Reitan (e.g., 1955). Neuropsychological assessment techniques for diagnosis and treatment have been recognized by the American Academy of Neurology (AAN) in an official report of its Therapeutics and Technology Assessment Subcommittee (American Academy of Neurology, 1996) and many scientific publications (e.g. Horton, 1997, 2008; Reitan, 1955, 1958, 1964a, 1964b, 1966, 1967, 1975, 1994; Reitan & Wolfson, 1986, 1992, 1993, 2002, 2008). Reitan had been given many awards for his important contributions to clinical neuropsychology from the National Academy of Neuropsychology (NAN) and the American Board of Professional Neuropsychology (ABN). In addition, the CPT code for neuropsychological testing lists the “Halstead Reitan battery” as neuropsychological testing. Clinical neuropsychological testing results have been well accepted in settings such as medical, educational, and legal arenas (Zillmer, 2004). The central premise of clinical neuropsychology is that there are direct and predictable behavioral correlates of structural lesions in the neocortex (Reitan & Davison, 1974). The hope and expectation is this article will be helpful in terms of facilitating an understanding of the important research and clinical contributions of Ralph M. Reitan, PhD, ABPP (CL), ABN.