Neuropsychological Assessment chapter 28 R. L. was a 32-year-old nurse and mother of four. Driving home from work one afternoon, she stopped at a red light and was rear-ended by another vehicle. R. L.’s head snapped back and struck the head rest and then the side window as she bounced forward. She blacked out for a few minutes, but, when the emergency vehicles arrived, she was con- scious, although disoriented and dysphasic, in addition to having severe pain in her back and neck from the whiplash. R. L. spent about a week in the hospital, where neither CT nor MRI scans identified any cerebral injury, although several vertebrae were damaged. An accomplished musician, she could still play the piano well from memory, but she could no longer read music. In addi- tion, her oral language skills remained impaired and she was completely unable to read. R. L.’s difficulties did not abate, and she had spells of apraxia. For example, she often found herself unable to figure out how to put on her makeup; she would stare at her lip- stick and have no idea how to use it. When R. L. came to us, she was depressed because, although the neurologists could find no reason for her impairments, she continued to have significant difficulties. Our neuropsychological evaluation revealed a woman of above- average intelligence who had a significant loss of verbal fluency and verbal memory, as well as severe dyslexia even a year after the accident. Now nearly 10 years later, she is still unable to read music and reads text only with great difficulty. L.’s case illustrates one of the remaining problems in clinical neurology. R People with closed-head injuries often have no sign of cerebral injury vis- ible on neuroimaging but still have significant cognitive deficits, often so se- vere that they cannot resume their preinjury life styles. For many, the only evidence of neurological disorder comes from neuropsychological tests. The 1980s were the heyday of neuropsychological assessment. Clinically trained neuropsychologists were in demand and neuropsychological evaluation was regarded as an essential tool in neurological assessment. The role of neu- ropsychological assessment has changed radically, however, and it has begun to develop a new face that is likely to continue changing for some time. In this chapter, we describe this changing role for neuropsychological assessment, consider the rationale behind assessment, and present summaries of six actual case assessments. 751 CHAPTER 28 NEUROPSYCHOLOGICAL ASSESSMENT 752 The Changing Face of Neuropsychological Assessment The roots of neuropsychological assessment lie in neurology and psychiatry. Clinician Kurt Goldstein, for example, was expert in neurology, psychology, and psychiatry. The psychological basis of assessment began to diverge from medicine in the 1940s. The first neuropsychological tests were designed to identify people suffering from cerebral dysfunction attributable to some type of organic disease process (brain pathology), rather than to “functional disor- ders” linked to behavior. Although test designers originally believed that it would be possible to con- struct a single test for brain damage and to establish a cutoff point that sepa- rated the brain-damaged from the non-brain-damaged patient, the task proved to be impossible. Gradually, more-sophisticated testing procedures were de- veloped, largely in a few locations in Europe and North America, including Cambridge (Oliver Zangwill), Oxford (Freda Newcombe), Moscow (Alexander Luria), Montreal (Brenda Milner and Laughlin Taylor), Boston (Edith Kaplan and Hans-Leukas Teuber), and Iowa City (Arthur Benton). By the early 1980s, neuropsychology was no longer confined to a few elite laboratories, and the new field of clinical neuropsychology blossomed in clin- ics and hospitals. Since that time, three factors have enhanced the rate of change in neuropsychological assessment: functional imaging, cognitive neu- roscience, and managed health care. We consider each briefly. Functional Imaging Perhaps the biggest change in both neurology and neuropsychology in the past 25 years has been the development of functional imaging. Indeed, we have em- phasized the importance of functional imaging in the Snapshots in Chapters 6 through 27. Thus, whereas in earlier eras the effects of cerebral injury or dis- ease often had to be inferred from behavioral symptoms, neuroimaging has al- lowed investigators to identify changes in cerebral functioning in a wide variety of disorders, including most of the neurological and behavioral disorders dis- cussed in Chapters 26 and 27. The main role of the clinical neuropsychologist therefore has changed from one of diagnosis to one of participating in rehabilitation, especially in cases of chronic disease such as stroke and head injury. An important point to bear in mind, however, is that even the most sophisticated functional imaging tech- niques often do not predict the extent of behavioral disturbance observed in people with certain types of brain injury, especially in head trauma, as R. L.’s case illustrates. For people with closed-head injury, the only way to document the nature and extent of their disabilities is by a thorough neuropsychological assessment (see Christensen and Uzzell). Cognitive Neuroscience One effect of the growth of clinical neuropsychology is the diversification of methods used by individual neuropsychologists, the choice of tests varying with the disorder being investigated. Indeed, there are now two texts that CHAPTER 28 NEUROPSYCHOLOGICAL ASSESSMENT 753 summarize the various tests available (one by Lezak and the other by Spreen and Strauss). From the early 1950s through the early 1980s, batteries of tests were devel- oped, each with a different focus (Table 28.1). Many of these test batteries, such as the Halstead-Reitan Battery, retained the concept of cutoff scores, although this assumption presents difficulties because performance below a particular level cannot always be taken as being indicative of brain damage. For one thing, cerebral organization varies with such factors as sex, handedness, age, educa- tion, and experience. Furthermore, test problems can be solved by using differ- ent strategies and can thus entail different cortical regions. Symptoms of cortical injury can be highly specific (recall the color-blind painter’s case de- scribed in Chapter 13). Finally, because many tests require problem solving of various kinds, we might expect task performance to vary with intelligence. All these factors make the use of cutoff scores difficult to justify. A serious handicap in the development of test batteries was the absence of theory in test construction or use. Knowledge of brain function was based largely on clinical observation, and few clinicians other than Alexander Luria had tried to formulate a general theory of how the brain functions to produce cognition. The emergence of cognitive neuroscience in the 1990s produced a dramatic change in the theoretical understanding of brain and cognition. Case studies once again became popular, each directed by sophisticated cognitive theory and assisted by structural and functional imaging technologies (see Shallice). These more-cognitive approaches also use multivariate statistical methods such as structural equation modeling to attempt to understand the way in which neural networks are disrupted in both individual cases and in groups. Test design has begun to incorporate this knowledge, but the emerging field of cognitive neuroscience will certainly change the way in which neuropsycho- logical assessment is conducted in the future. Perhaps the area most influenced to date is in understanding the functions of the right frontal lobe (see a review by Stuss and Levine). Historically, the right frontal lobe proved remarkably unresponsive to neuropsychological assessment. The combination of functional imaging and neuropsychological test develop- ment has now led to an understanding of the role of the right frontal lobe in previously inaccessible functions such as social cognition (see Chapter 22). Table 28.1 Overview of neuropsychological test batteries Test battery Type Basic reference Benton’s neuropsychological investigation Composite Benton et al., 1983 Boston Process Approach Composite Kaplan, 1988 Oxford neuropsychological procedures Composite Newcombe, 1969 Montreal Neurological Institute approach Composite Taylor, 1979 Frontal lobe assessment Composite Stuss and Levine, 2002 Western Ontario procedures Composite Kimura and McGlone, 1983 Halstead-Reitan Battery Standardized Reitan and Davison, 1974 Luria’s neuropsychological investigation Standardized Christensen, 1975 Luria-Nebraska Standardized Golden, 1981 CanTab Computerized Robbins et al., 1998 CHAPTER 28 NEUROPSYCHOLOGICAL ASSESSMENT 754 Managed Care Perhaps economics is the greatest challenge faced by practicing psychologists in the past decade. In the era of managed health care, clinicians are pressured to reduce the time and money spent on neuropsychological services. In particular, there is sometimes unreasonable pressure to reduce the number of tests given to individual patients, especially in view of the perception that medical imaging can provide faster and more accurate assessments of cerebral dysfunction. As already noted, imaging has changed the way in which neuropsychologi- cal assessment will be used, but, in cases of head trauma, as R. L.’s case demon- strates, neuropsychological assessment is often the only way to document cognitive disturbances. Groth-Marnat