Neuropsychology for Neurologists
by David W. Loring, PhD & Kimford J. Meador, MD
INTRODUCTION
Neuropsychological evaluation is an important adjunct in the evaluation
of selected neurologic patients. It serves as an extension of the mental
status examination, and employs standardized measures to evaluate
performance relative to the entire population or to specialized
subpopulations (e.g., patients with less than a high school education).
Neuropsychological evaluation allows for a qualitative interpretation
of problem solving strategies in addition to the quantitative results.
However, neuropsychological evaluation is not appropriate for all patients
with cerebral disease or even all patients with impaired cognitive
functioning. Variability also exists in the training and experience of
psychologists performing neuropsychological testing, which may effect the
validity and reliability of the neuropsychological findings. In this
seminar, we will examine common approaches to neuropsychological
assessment, training issues, and use and misuse of neuropsychological
tests. Pediatric neuropsychology, including assessment of learning
disabilities, will not be discussed.
BACKGROUND
For many years, the Halstead-Reitan Battery was synonymous with
neuropsychological testing in the United States. The Halstead-Reitan
battery consists of a series of tests chosen by Ward Halstead at the
University of Chicago in the 1930s to investigate the effects of brain
injury on cognitive abilities. These tests were subsequently applied to
different clinical populations in the 1950s by Ralph Reitan to assist with
the detection of brain damage or "organicity." The Halstead-Reitan
Battery consists of the Category Test, Tactual Performance Test, Seashore
Rhythm Tests, Speech Sounds Perception Tests, Finger Tapping Test, and
Trail Making. With this approach, performance is classified as normal or
impaired for each test. Based upon the proportion of tests passed and
failed (i.e., Halstead Impairment Index), the patient is considered either
normal or brain impaired. In addition to the above tests, the Aphasia
Screening Test, a Sensory-Perceptual Examination, and grip strength have
been added although performance on these tests is not considered in the
Impairment Index.
Although many neuropsychologists still administer the Halstead-Reitan
battery, a gradual shift away from this test battery has occurred since
the role of neuropsychological assessment in most contexts is no longer to
detect "organicity," but rather, to assess the cognitive and
behavioral deficits associated with known cerebral lesions. Many
neuropsychologists, however, continue to use selected tests from the
Halstead-Reitan Battery in their clinical evaluations.
Despite neuropsychology's diminished role in the detection and
localization of cerebral lesions, most neuropsychological batteries are
constructed to assess standard neurobehavioral aspects of brain impairment
associated with focal brain lesions or obtained through the study of
patients with traditional neurobehavioral syndromes. The areas most
commonly assessed include general intellectual function (i.e., IQ),
language, visual spatial ability, memory and learning, attention and
concentration, motor/sensory function, abstraction and executive function,
and personality. A comprehensive listing and description of specific tests
that may be used in neuropsychological assessment can be found in Lezak
(1995).
NEUROPSYCHOLOGICAL ASSESSMENT TESTS AND PROCEDURES
Most neuropsychologists obtain standard intellectual measures including
Full Scale IQ, Verbal IQ, and Performance IQ. In adults, the most commonly
employed intelligence test is the Wechsler Adult Intelligence
Scale-Revised (WAIS-R). The three summary IQ measures are derived from
averaging individual subtest scores. Thus, unless diffuse decline in
cognitive abilities exists (e.g., dementia or head injury), the usefulness
of the summary measures is limited (Lezak, 1988). Nevertheless, by
tradition if nothing else, these scores are dutifully reported in the
neuropsychological report. Of more interest is specific IQ subtest
performance, and most neuropsychologists interpret test scores with
non-IQ subtest measures of similar neuropsychological constructs (e.g.,
WAIS-R Block Design compared with the Rey-Osterrieth Complex Figure). Full
Scale IQ measures are helpful in selected cases such as in head injury
because, in addition to reflecting diffuse cognitive decline, they are
familiar and many believe (erroneously) that they know what IQ scores
mean. One major advantage of IQ tests is their large-scale formal
standardization with excellent normative information.
Academic Achievement
Achievement testing usually consists of reading single words, spelling,
and arithmetic. Achievement tests such as the Wide Range Achievement Tests
(WRAT) are well standardized and provide good measures of scholastic
attainment or accomplishment. However, the reading subtest requiring
pronunciation of single words is often used to estimate premorbid level of
function. As the test gets harder, words are presented that cannot be
pronounced correctly based upon phonics (e.g., paradigm). Thus, correct
pronunciation is taken as evidence of prior familiarity, and unless the
patient is aphasic, provides one measure to estimate level of function
prior to an accident or disease.
Other measures of academic achievement are more specialized and are
commonly employed in school-aged children when learning disability or
attention deficit disorders are being evaluated. These tests may include
measures of reading comprehension for paragraphs, receptive vocabulary
(e.g., point to the picture of an owl), or reading recognition.
Language
Language is commonly assessed with the Aphasia Screening Test of the
Halstead-Reitan Battery. However, this test yields primarily qualitative
information. It is frequently supplemented by examining generative verbal
fluency (how many words can be generated beginning with either a
particular letter of the alphabet or from a specific semantic category
such as fruits and vegetables), confrontation naming (e.g., Boston Naming
Test or Multilingual Aphasia Examination Visual Naming Test), or
comprehension (e.g., Token Test). Comprehensive aphasia batteries such as
the Boston Diagnostic Aphasia Examination, Multilingual Aphasia
Examination, or Western Aphasia Battery are typically not administered
unless there are specific questions regarding aphasia subtyping or the
need to fully delineate language functioning exists.
Visual Spatial
Visual spatial ability is assessed with a variety of tests, the most
familiar of which are the WAIS-R Block Design test and the Rey-Osterrieth
Complex Figure. Although the Bender Gestalt test has been frequently used
to assess visual motor function, it has been used less over the last
decade, perhaps due to poor standardization and scoring criteria and the
presence of newer tests of visual spatial function. Other commonly used
tests include the Visual Retention Test, Judgement of Line Orientation and
Facial Recognition Tests of Benton, and the Hooper Visual Organization
Test.
Attention/Concentration
Attention and concentration can be measured with a variety of
neuropsychological tests. From the Halstead-Reitan Battery, the Seashore
Rhythm Test and Speech Sounds Perception Test are sensitive to attentional
deficits. Many neuropsychologists continue to use these tests as measures
of right and left temporal lobe function, but recent research from
Reitan's laboratory shows that although both are good measures of
attentional processes, they are poor measures of lateralized temporal lobe
impairment (Reitan & Wolfson, 1989; Reitan & Wolfson, 1990). Trail
Making A and B require the patient to connect either numbers, or alternate
between numbers and letters (i.e., 1-A-2-B, etc.), distributed in a
spatial array. Although Trail Making can be affected by visual spatial
impairment due to a significant scanning component, the time to completion
makes it also sensitive to attentional impairments. The task alternation
aspect of Trail Making B makes it sensitive to certain aspects of
executive/frontal lobe function.
Digit span from the WAIS-R (both forward and backward) is a good
measure of gross attention, although vigilance tests (i.e., Continuous
Performance Test in which the patient responds only when the letter
"X" is flashed among a series in individually presented letters,
or to respond only to the letter "X" if immediately preceded by
the letter "A") and reaction time measures may be obtained when
a more fine-grained analysis is necessary. The Paced Auditory Serial
Addition Tests (PASAT) is a measure of sustained attention, and requires
the patient to add pairs of serially presented randomized numbers so that
each number is added to the number immediately preceding it.
Memory and Learning
Memory is most often assessed using the Wechsler Memory Scale (WMS) or
its revision (WMS-R). However, the WMS has been criticized on both
methodological and theoretical grounds (Erickson and Scott, 1977; Loring
and Papanicolaou, 1987). The WMS, published in 1945, yields a memory
quotient, or MQ, that may be informally contrasted with a patient's IQ to
suggest if a relative impairment exists in memory functioning. However,
the individual subtests contributing to the MQ were not standardized, and
several subtests contained constructs that, although necessary for
successful memory performance, are not genuine measures of memory (e.g.,
Orientation and Mental Control). In addition, the WMS does not examine
retention of information over time.
The most commonly employed WMS subtests that are individually
administered include Logical Memory, Visual Reproduction, and Paired
Associate Learning. Logical Memory is a test of paragraph or prose passage
recall. Visual Reproduction examines immediate reproduction of simple
geometric designs. Paired Associate Learning tests the ability to form
associations between word pairs, some of which are easy (e.g.,
penny/quarter), and some of which are difficult (yield/page). When
selected subtests are administered, a 30 minute delay component is often
obtained (e.g., Russell, 1975). Significant limitations of the WMS include
lack of adequate scoring criteria for memory units of the paragraph, and
lack of adequate normative information.
The WMS was revised in 1987, and in addition to retaining the commonly
employed subtests described above, added several new subtests although
many problems associated with the test remain (Loring, 1989). Five summary
measures are derived from performance on this test: General Memory, Verbal
Memory, Visual Memory, Delayed Recall, and Attention Concentration. The
WMS is now undergoing revision and restandardization and will most likely
be called the WMS-III.
The other major self-contained standardized collection of memory
subtests is the Memory Assessment Scales (Williams, 1990). The specific
content of the items differs from the WMS-R, but it also yields summary
measures for General Memory, Verbal Memory, and Visual Memory. It is less
popular than the WMS-R, but in our experience at the Medical College of
Georgia, it frequently provides lateralizing information in candidates for
anterior temporal lobectomy.
Many neuropsychologists give word list learning tasks as additional
measures of verbal memory. The most common word list learning tests are
the Rey Auditory Verbal Learning Test, California Verbal Learning Test,
and Buschke Selective Reminding Test. Visual memory is frequently assessed
using the Rey-Osterrieth Complex Figure. However, the specificity of
visual memory impairment to right temporal lobe dysfunction is much less
than that associated with verbal memory deficits and left temporal lobe
impairment. Although the Benton Visual Retention is sometimes employed as
a visual memory test, it does not examine retention of material over long
delays, and is generally considered as a test of visual construction or
visual attention. The Memory Assessment Scale is a battery of tests
similar in construction to the WMS, and yields a general memory measure in
addition to verbal and visual memory summary scores.
Executive Function/"Frontal" Lobe Tests
Tests of executive function, informally called frontal lobe tests, most
commonly include the Wisconsin Card Sorting Test (WCST) and Halstead
Category Test. In the WCST, the subject is given a deck of cards that can
be sorted into different categories based upon color, shape, and number.
It is the subject's task to figure out how to sort the cards based solely
on feedback from the examiner whether each response is "correct"
or "incorrect." The Category Test is similar, although each
stimulus represents a number from 1-4 and it is the patient's task to
figure out what aspect of the stimulus is used for number representation.
The only information given to the patient concerns the correctness of the
response. Consequently, the patient must engage a series of hypotheses to
learn the underlying principle. Tests of maze performance may also be used
to assess planning and impulse control. Trail Making B is sensitive to
task alternation difficulty (1-A-2-B).
Sensory and Motor Function
Tests of sensory and motor function are tested to varying degrees
depending both upon the patient population and the biases of the examiner.
Common tests of motor and fine motor function include the finger tapping
and grooved pegboard tests. Grip strength is assessed with a hand
dynamometer. Sensory testing may consist of measures of stereognosis from
the Halstead-Reitan Battery, although this test is sensitive to
inter-examiner variability. The Halstead-Reitan Battery tactual
performance test requires the blindfolded patient to feel different shapes
and to fit them into a formboard. However, many factors contribute to the
tactual performance test (visual spatial ability, memory, motor function),
making this test sensitive to brain impairment independent of its
location.
Task Motivation/Test Validity
In patients with mild head injuries, neuropsychological test
performance may be the only evidence of cerebral involvement. However, the
neuropsychological evaluation is dependent on patient motivation and
compliance, and consequently, not all performances in the
"impaired" range reflect brain pathology. Although inclusion of
explicit measures of task motivation and test validity should be included
in all neuropsychological assessments, it is particularly true when a
strong financial incentive to perform poorly on neuropsychological tasks
exists.
As with the neurologic evaluation, inconsistent performance may suggest
malingering or, at least, failure to put forth one's best effort. However,
other factors such as anxiety and fatigue may produce neuropsychological
test inconsistencies. Measures of task motivation and test validity
include clinical judgement based upon standard neuropsychological tests,
validity measures from the MMPI, performance patterns present in existing
neuropsychological testing, and formal measures designed explicitly to
detect performance distortion (e.g., forced-choice symptom validity
checking).
Clinical judgement may be used to infer less than maximum task
performance (e.g., an IQ of 60 following a minor head injury with no loss
of consciousness), although often clinical experience alone is not a good
indicator of motivation (e.g., Heaton et al., 1978). The MMPI contains
explicit validity measures, and evidence on the MMPI suggesting that the
patients are purposely presenting themselves poorly may be generalized to
other test results.
Symptom Validity Memory Testing typically employs a forced choice
recognition format for numbers (e.g., Hiscock & Hiscock, 1989). A
series of digits is presented, typically on a computer screen. Following a
delay ranging from a few seconds to as long as 30 seconds or more, two
number sequences are presented from which the subject makes a selection.
Feedback regarding correctness of response is given, and getting the
correct answer at least half the time may make some patients get the
impression that they are doing "too well" and begin purposely
choosing the incorrect answer. Thus, performance of actively malingering
patients may be below chance. As noted by Lezak (1995), the malingering
patient may find it difficult to score within chance over many repeated
trials.
Symptom validity testing results are unequivocal when the specific
statistical probabilities of less than chance responding is obtained.
Thus, the strongest evidence of malingering occurs when a patient scores
significantly below chance, indicating that there has been a deliberate
attempt to answer incorrectly. To score below chance, the patient must
identify the correct answer and then choose the opposite and incorrect
answer. That is, a patient must recognize the correct answer significantly
above chance to score significantly below chance. Unfortunately, not all
suspected malingerers perform worse than chance.
Simple "memory" tests are also frequently used. The most
widely employed test in this approach is the 15 item (or 3x5) memory task
described by Rey (in Lezak, 1995). The patient is presented with 15 items
to "memorize," but in fact, due to immediate recall and the
multiple redundancies in the stimuli, this is an extremely simple task.
This technique relies on the examiner repeatedly informing the patient how
hard the task is.
Personality
Most patients are administered some measure of personality function in
addition to the tests of cognitive abilities. The most common approach is
to use the MMPI/MMPI2, although some neuropsychologists may choose
different inventories such as the MCMI/MCMI2. The need for measures of
personality function is clear when performing an evaluation of possible
dementia vs. depressive pseudodementia. However, personality testing is
not used to determine the likelihood of cerebral compromise. Further,
these inventories are unable to determine, for example, the amount of
depression that is the primary result of cerebral injury vs. the amount
that may be a psychological reaction to cerebral injury. Projective tests
of personality are generally not employed in a neuropsychological context
unless they are administered as part of a larger series of tests that
includes objective measures such as the MMPI.
Personality assessment using the MMPI is frequently helpful in the
evaluation of low back pain and in the prediction of outcome following
back surgery. In addition, the MMPI may provide information regarding the
personality contributions to medical disease including neurologic disease.
Frequently, the neurologist may request personality assessment to help in
the evaluation of back pain patients or to evaluate if a person's
personality characteristics are significant clinical factors. When
personality assessment is performed, it may be performed by clinical
psychologists without specialized training and expertise in cognitive
aspects of clinical neuropsychology. However, in certain cases of
personality contributions to clinical complaints in patients with cerebral
disease, background in neuropsychology is helpful in overall patient
evaluation.
WHEN TO REFER FOR NEUROPSYCHOLOGICAL ASSESSMENT
Not all patients with cognitive or behavioral deficits from brain
injury should be referred for neuropsychological assessment. Although the
threshold for each neurologist to make referral will be based in part on
the experience and comfort with which they examine patients with
neurobehavioral deficits, some guidelines are helpful in choosing which
patients will benefit from neuropsychological assessment.
Patients who complain of cognitive deficits and have normal or
minimally impaired mental status examinations are frequently candidates
for neuropsychological assessment. Neuropsychological testing is often
most helpful when the deficits are mild. In cases of elderly patients who
are experiencing normal age-related decline in mental status,
neuropsychological testing may help to identify whether the subjective
memory impairment is due to normal aging or may be related to early stages
of a progressive dementia. Although neuropsychological testing cannot
always help in the diagnosis of dementia during the earliest stages, it
provides a reliable baseline against which subsequent evaluations can be
compared to detect cognitive change. In addition, normal
neuropsychological testing reassures elderly patients who are concerned
that they may be developing Alzheimer's disease, and neuropsychological
testing may be considered for certain cases in which cognitive decline is
not suspected strictly to provide patient reassurance.
Not all cases of dementia or probable dementia require
neuropsychological evaluation. Neurologists comfortable with dementia
assessments may request neuropsychological evaluation only for unusual or
atypical cases. However, neurologists whose practices encounter dementia
cases less frequently may request neuropsychological assessment to make
that diagnosis with greater confidence.
Patients with clear cognitive impairment may undergo neuropsychological
evaluation, not for diagnostic consideration, but to help in competency
issues such as driving, work, ability to manage funds, live independently,
or to take medications. Similarly, patients with non-progressive
neurologic disease may benefit from neuropsychological evaluation for
management or rehabilitation issues, or assist in disability determination
or readiness to return to work or school.
Patients with little formal education are frequently as difficult to
assess with a battery of neuropsychological tests as they are with a
bedside mental status evaluation and may not benefit from extended
evaluation. A 75-year-old with two years of education and a lifelong
history of manual labor may indeed have dementia, but it is a rare patient
with this type background in which neuropsychological assessment provides
information beyond that which can be obtained at the bedside. The norms
that exist for patients with limited education simply do not exist, and
the sensitivity of all neuropsychological tests is less at the low extreme
of the distribution. Thus, neuropsychological testing, either with
dementia rating scales (e.g., Mattis Dementia Rating Scale) or more
traditional neuropsychological testing in these cases is used primarily
for establishing a baseline to monitor disease progression.
STATISTICAL PROPERTIES OF TESTS
The best standardized tests, such as IQ tests, typically yield
standardized scores that have a mean of 100 and a standard deviation of
15. Most neurologists are familiar with the general qualities of IQ scores
such as mental retardation being labeled for IQs less than 70. As with any
standardized distribution, about two-thirds of the population fall between
-1 SD and +1 SD around the mean. With IQ scores, approximately two-thirds
of the population has an IQ between 85 and 115. Approximately 95% of the
population has an IQ that fall between -2 SD and + 2 SD (IQs between 70
and 130).
Because of these (and other) properties, the corresponding percentile
difference between two IQ scores that differ by a fixed number of IQ
points is not always the same. For example, an IQ of 75 corresponds to the
5th percentile, an IQ of 85 corresponds to the 16th percentile, an IQ of
95 corresponds to the 37th, and an IQ of 105 corresponds to a percentile
of 63. Thus, the percentile difference for 10 IQ point change is 11
percentile points from IQs 75-85, 21 percentile points for IQs 85-95, and
26 percentile points for IQs 95-105. Similar relationships are present for
other transformed scores such as scaled scores.
Norms for very old patients are limited. The WAIS-R provides norms only
through age 74 years. There have been efforts by the Mayo clinic to obtain
norms on healthy patients into the 90s (e.g., Ivnik et al., 1992),
although this sample of subjects is better educated than average.
The sources of normative information also vary. Tests such as the
Wechsler Intelligence Scales, Wechsler Memory Scale-Revised, Memory
Assessment Scale, and Achievement tests have undergone formal
standardization and have normative tables that are reliable and generally
reflect the population at large. However, most other neuropsychological
measures have not undergone formal standardization, and in consequence,
the source of normative information is typically based upon published
reports of healthy volunteers or control subjects and can be based on
relatively few subjects. Many different sources of normative information
exist for many commonly employed neuropsychological measures, and the
choice among several normative tables is not necessarily a trivial issue.
Large discrepancies in interpretation may occur based upon the normative
tables selected by the neuropsychologist for comparison. As pointed out by
Van Gorp (1995), for example, a score of 28 seconds on Trail Making Part A
in a 45-year-old patient with an 11th grade education may yield
performances ranging from the 8th percentile (Bornstein, 1985) to the 75th
percentile (Davies, 1968). For this reason, we recommend the presentation
of raw scores in addition to percentile rankings and clinical
interpretation.
Variability also exists in how certain neuropsychological tests are
administered, and this will also effect how comparable the selected norms
are. The two tests subject to the greatest variability in administration
are the Logical Memory subtests from the original Wechsler Memory Scale
and the Rey-Osterrieth Complex Figure. In the Logical Memory subtest
(prose passage recall), scoring criteria do not exist to define what
constitutes correct recall of each memory unit. Some neuropsychologists
require verbatim recall, some will score the item as recalled if the gist
of the element is remembered (e.g., kids for little children), and others
employ a half credit scoring approach. Similar scoring ambiguities exist
for the Complex Figure. Although the 36 scorable elements are described,
the only criteria given are for whether the element is correctly placed,
and whether or not the element is distorted or incomplete. Thus,
considerable scoring variability exists among neuropsychologists for this
test.
NEUROPSYCHOLOGICAL REPORTS
As with other laboratory procedures, the written report serves as the
primary permanent record of the patient's performance. However, the
neuropsychologist typically retains all of the scoring and test forms
although this specific information is not routinely available to the
referring physician. This situation is analogous to EEGs, in which a
formal report is written describing the patient's record, but copies of
individual EEG tracings are not included with the report.
A consensus does not exist within the neuropsychological community
regarding the amount of test detail that should be included in a
neuropsychological report. At one extreme is the position that only
performance description should be included which, although based directly
on neuropsychological test performance, does not mention tests by name.
Thus, statements such as "verbal memory was severely impaired
although more normal memory was present when a contextual cue for
information was provided" or "severe visual-constructional
deficits were observed" may serve as the primary source of
information.
The rationale for not including specific test scores in a report is
that not only are they meaningless for the vast majority of persons
reading the report, but in addition, neuropsychological scores including
IQ measures are subject to considerable misunderstanding and potential
misuse. Thus, the scores are withheld from the formal report but are made
available to appropriate individuals if they are requested.
At the other end of the spectrum is the presentation of all scores and
percentiles. Some neuropsychologists will include scores with their
description and interpretation, and others will present the scores
separately as a summary information sheet. The rationale behind this
approach is that since one strength of neuropsychological assessment is
the systematic application of standardized tests, not to present the
information is analogous to throwing away information. Specifically, it
allows the referring individual to examine the performance and, perhaps,
arrive at different conclusions. To not include information would be
analogous to not providing CT or MRI films for evaluation and relying
solely on the written interpretation of the scan. However, even when
scores are presented in the report, the referring physician should be
aware that the reliability of the corresponding percentile values may vary
both as a function of the test and as a function of which particular set
of norms is employed as discussed above.
INTEGRATION OF NEUROPSYCHOLOGICAL RESULTS WITH CLINICAL HISTORY AND
NEUROLOGICAL FINDINGS
As with any consultation, posing a specific referral question and
direct communication with the consultant will increase the likelihood of
obtaining information that address the clinician's concern and provides
valuable information for the care of the patient. The neuropsychological
findings must then be interpreted within the context of the clinical
history and neurological examination. For example, the neuropsychological
finding of moderate anterograde memory deficits has distinctly different
implications in an 18-year-old patient with recent head trauma compared
with identical findings in a 76-year-old patient complaining of slowly
increasing memory difficulty. In addition, the pattern of neurological and
neuropsychological findings may be complimentary and thus enhance the
diagnostic significance above either individual finding alone. For
example, neuropsychological evidence of a mild language disorder in a
patient with an equivocal right Babinski reflex increases the probability
of a left hemisphere lesion.
CLINICAL JUDGEMENT AND EXPERIENCE
Experience is frequently used to justify an assertion that a patient
put forth his or her best effort. However, clinical experience in
neuropsychology is not sufficient to make reliable inference regarding
potential malingering. A favorite question of defense attorneys is
"If you were fooled, doctor, how would you know you were
fooled?"
Heaton et al. (1978) reported the ability of neuropsychologists to
detect faked neuropsychological performance. Level of general impairment
(Halstead Impairment Index or FSIQ) was equivalent in moderate to severe
head injury patients and in healthy subjects instructed to fake
neuropsychological deficits. However, different patterns of deficits were
produced. The malingerers tended to obtain high scores on the MMPI F scale
and performed poorly on sensory and motor tests. However,
neuropsychologists' ability to classify patients correctly as malingerers
or head injury patients based solely upon neuropsychological test
performances ranged from chance-level prediction to about 20% better than
chance.
PROFESSIONAL QUALIFICATIONS AND TRAINING
Successful completion of a medical residency and board eligibility is
frequently used to insure adequate training in medical specialties.
However, clinical neuropsychological training is more variable, and
consequently, relying on board eligibility is even more important since it
serves as an independent criterion with which to evaluate "education,
training, and experience." The definition of a clinical
neuropsychologist adopted by Division 40 (Clinical Neuropsychology) of the
American Psychological Association describes the minimum training, and
indicates that attainment of the American Board of Professional
Psychology/American Board of Clinical Neuropsychology diploma is "the
clearest evidence of competence as a Clinical Neuropsychologist."
Thus, the neuropsychologist must have successfully completed both
systematic didactic and experiential training in neuropsychology and
neuroscience at a regionally accredited university. Current standards do
not allow a psychologist to become a neuropsychologist by simple
postdoctoral supervision, and the physician is entirely justified if a
neuropsychologist does not hold an ABPP/ABCN diploma to ask about what
formal training (other than supervised experience) has been obtained.
As with physician guidelines, board "eligibility" rather than
board certification may be a useful measure of "education, training,
and experience." Since the criteria described in the definition of a
clinical neuropsychologist are essentially those requirements for
eligibility for the ABPP/ABCN diploma, board eligibility should be the
standard to insure adequate training in clinical neuropsychology. Although
other boards of professional neuropsychology exist (i.e., American Board
of Professional Neuropsychology, or ABPN [which is not the American Board
of Psychiatry and Neurology]), they are not held with the same esteem as
ABPP/ABCN.
FUTURE DIRECTIONS
Clinical neuropsychology has been an area of rapid expansion and
application in the 1980s. The rate of growth has slowed in the 1990s,
although part of this slowing is undoubtedly due to concerns in the
rapidly changing medical marketplace.
Neuropsychology has always embraced change and new approaches to
assessment. Part of the changes that will continue to occur include
improvement in sampling and normative information for current approaches
to assessment. However, there will probably also be more fundamental
changes in the approach to neuropsychological assessment that will occur
that capitalizes on the rapid development of computers and virtual
reality. Neuropsychology has been criticized for not testing enough real
world behaviors. Consequently, driving capacity must be inferred
indirectly based upon some informal combination of psychomotor speed,
visual scanning ability, and general judgment. It soon may be possible to
test driving in a virtual reality computer simulator in which specific
conditions are presented and the patient's response measured directly. The
conceptual extensions are limitless, and include shopping, cooking, or
dressing simulations.
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~~~~~~~~~~
© 1995, American
Academy of Neurology.
Authors - David W. Loring, PhD & Kimford J. Meador, MD,
Department of Neurology, Medical
College of Georgia, Augusta, Georgia, USA, 30912-3275.
Source - Presented at the Annual Meeting of the
American Academy of Neurology, Seattle, Washington, May 12, 1995.
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