A neuropsychologist is a psychologist who specializes in studying brain behavior relationships. Neuropsychologists have extensive training in the anatomy, physiology, and pathology of the nervous system. Some neuropsychologists specialize in research while other neuropsychologists specialize in evaluating and treating people who are thought to have something wrong with the way in which their nervous system is functioning.
Neuropsychologists study brain behavior relationships under very specific circumstances which are both controlled and standardized. As a general rule, this means using tests which have been validated and which have been shown to have acceptable levels of sensitivity and specificity. This means the test can measure the thing it is trying to measure even when the thing it is trying to measure is only present in small amounts and it also means the test can distinguish the thing it is trying to measure from other things.
If we wish to measure a thing “A” then the test has to be able to measure”A” even when very little of “A” is present; this is sensitivity. Specificity means when we measure “A” with our test, we know that the test does not measure “B”, “C,” or “D.”
Clinical neuropsychologists evaluate patients using one of three general methods. The first method is to use an assessment technique in which a fixed battery of tests is given and in which we only want to know what functions are impaired and what functions are not impaired.
The most commonly used representative of this type of test is the Halstead – Reitan Neuropsychological Battery. The second method is to use an assessment technique in which a fixed battery of tests is given but in this method there is a hierarchical each subtest so that if a function is impaired, the level at which it is impaired can be determined. The most common representative of this type of test is the Luria – Nebraska. Common to both of these tests is a long history of research studies examining the ability of the two batteries to measure dysfunction of the brain and to accurately identify why that dysfunction is occurring.
The third method used by neuropsychologists is the flexible battery approach. By definition, the flexible approach is not a battery because when one uses this approach one gives a group of tests allegedly picked for just the particular patient. This means that the particular group of tests is not given to other patients and it is not
Neuropsychology involves the study, evaluation, and treatment of known and suspected brain disorders using the methods of psychology.
“How do neuropsychologists study these brain/behavior relationships?” Classically, brain/behavior relationships have been inferred from the study of individuals with head injuries, tumors, neurological disease, and other unpleasant brain pathologies. Behavioral changes are assumed to be due to this brain tissue damage. For instance, if a stroke caused damage to the very back of your brain, it is known that you will more than likely experience visual difficulties eventhough your eyes are perfectly intact. On the other hand, if the stroke caused damage to the very front of your brain, attention, lack of social insight, and sequencing difficulties would be expected. New brain imaging techniques have allowed us to study brain/behavior in people without brain injury, and not surprisingly, basically the same observations have been made. In a nutshell, a large group of the brain’s functions are said to be “localized” to different areas.
The last 5 to 10 years in behavioral neurology and neuropsychology have seen tremendous advances in the understanding of the brain bases of cognition, perception, and affect. This, in part is due to the development and growing availability of brain imaging techniques, as well as theoretical and methodological progress in cognitive psychology.
Behavioral Neurology and Neuropsychology, Martha J. Farah, Publisher: McGraw-Hill Companies, The
Pub. Date: January 1997
Traditionally defined, neuropsychology is the study of (and, the assessment, understanding, integration, and modification of) brain-behavior relationships. Neuropsychology seeks to understand how the brain, through structure and network functions, controls/produces behavior and mental processes, including emotions, personality, thinking, learning and remembering, problem solving, and consciousness. It is also concerned with how behavior may influence the brain and related physiological processes, as in the emerging field of psychoneuroimmunology (the study that seeks to understand the complex interactions among brain and immune systems, and their
implications for health).
Neuropsychology seeks knowledge about brain and behavior relationships through the study of both normal and damaged brain systems. It seeks to identify the underlying biological causes of behaviors, from creative genius to mental illness, that account for intellectual processes and personality. Clinical neuropsychology seeks such understanding, particularly, in the case of how damaged biological structures alter behaviors and interfere with their normal expressions.
If we presume that the brain is the starting point for why and how we process all mental information (not just cognitive, but interpersonal communications, self-concept, emotional reactivity, personality, learned responses, etc.), then in some aspect, all psychology is neuropsychology. Neurolinguistics, for example, is the study of how language shapes our self-concepts and our interpersonal communications. Neurodevelopmental psychology is the study of how behavioral and mental characteristics change with nervous system growth. Even psychological concepts of dreaming (and experience as a whole are subserved by brain (i.e., hard, physiological) processes. Cognitive and even basic Skinnerian psychology, which rely on theories of how environmental stimulus and behavioral response are connected, must account for the vital connecting linkthe brain.
Neuropsychology is an objective and scientifically based formal discipline for peeking into individual minds. Clinical neuropsychology seeks, ultimately, to understand the individual mind (and its normal as well as errant behaviors) and not just the broader, statistically normal mind. The discipline uses experimental procedures to compare performance among persons with known differences in their biological brain structures (within the limited criteria currently available for defining these differences), and to search for the myriad sources of variance that produce individual differences.
In the application of clinical neuropsychology, such understanding of the biological sources of individual differences helps identify brain-based disorders in memory, personality, self-awareness (conscious experience), cognition, and emotional expression. Working backwards, then, from a look at abnormal behavior obtained through formal tests, reasonable inferences about brain disorders can be reached. Understanding these neurofunctional changes (i.e., abnormalities) as a result of brain changes (i.e., injury) defines parameters for current and future behavioral expectations in the lifestyle of the individual. As our knowledge of brain plasticity improves, such understanding also provides realistic expectations for remediation (restoration or adjustment) of
Neuropsychological understanding is achieved through a comprehensive exploration of the neurophysiological foundation of behavior and seemingly infinite potential contributing factors. Everyones brain is wired differently, a product of native biological structure, past experiences, physical health, learned responses (and personality), injuries and diseases, and a host of other factors. Clinically, it is the role of the neuropsychologist to sort out the factors that influence how the brain is working to form expectations in the product, progress, and recovery from disease or injury.
Neuropsychologists use scientifically validated objective tests to measure brain functions. While CT scans, EEGs, and neurological examinations look at structure and physical condition of the brain, the neuropsychological examination is the only way to formally assess brain function. Neuropsychological tests cover the range from simple motor performance to complex reasoning and problem solving. In almost all cases of objective tests, quantitative results are compared with some normative standard, including groups of non-brain injured and groups of persons with varying kinds of brain injury. If the norms are based on age and educational achievement, good comparisons can be made between an individual’s performance and that of persons in known diagnostic categories and persons who do not have a diagnosis of brain injury.
Qualitative assessment of neuropsychological tests provides a look at the process of the individual in producing the
quantitative scores. The combination of objective scores and behavioral process observations made by the neuropsychologist constitutes the art and science of neuropsychological assessment.
The following listing includes some of the more frequently used neuropsychological tests and what they are intended to measure. In order to keep test content and applications confidential to preserve their clinical usefulness, this information is restricted to general information.
Purpose of Test
Wechsler Adult Intelligence ScaleIII
This set of 13 separate “subtests” produces measures of simple memory, knowledge, problem solving, calculation, abstract thinking, spatial orientation, and speed of mental processing. In addition to summary measures of intelligence, performance on each subtest has implications
for different neurofunctional domains. The set of tests takes about an hour or more to administer. The WAIS-III is often the foundation for a comprehensive neuropsychological assessment.
Wechsler Memory ScaleIII
This set of 18 separate “subtests” yields information about various kinds of memory and learning processes. Summary memory indices are provided in addition to the individual scores of the subtests. The whole set of tests takes about an hour to administer. The WMS-III provides a comprehensive assessment of memory.
Halstead Category Test
This test measures concept learning. It examines flexibility of thinking and openness to learning. It is considered a good measure of overall brain function.
Wisconsin Card Sort Test
Similar in concept to the Category Test, this procedure also measures the ability to learn concepts. It is considered a good measure of frontal lobe functioning.
Trail Making Tests A and B
These rather simple tests measure attention, visual searching, mental
processing speed, and the ability to mentally control simultaneous
stimulus patterns. These tests are sensitive to global brain status but are
not too sensitive to minor brain injuries.
A set of tests that examines language, attention, motor speed, abstract
thinking, memory, and spatial reasoning is often used to produce an
overall assessment of brain function. Some neuropsychologists use some
or all of the original set of tests in this battery.
This brief procedure examines attention and mental control.
Verbal Fluency (various)
There are a variety of verbal fluency tests used. Each is designed to
measure the speed and flexibility of thought processes.
This procedure examines ability to visually integrate information into whole
perceptions. It is a sensitive measure of moderate to severe brain injury.
Aphasia Tests (various)
Several aphasia and language tests examine level of competency in
receptive and expressive language skills.
California Verbal Learning Test
This procedure examines several aspects of verbal learning and memory.
Comparison of vocabulary knowledge and ability to figure out abstract
sequential patterns has been established as a sensitive measure of
general brain functioning.