Neuropsychological Assessment

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Neuropsychological Assessment

Definition

Neuropsychological assessment involves a series of tests in a controlled setting to help assess brain function in the areas of cognition, emotional health, and behavior.

Purpose

Neuropsychological testing is performed for a variety of reasons including:

to identify and characterize changes in the psychological health and function of an individual
to define the degree of the impairment in cognition and assist in determining its underlying cause
to determine how an impairment might affect the daily life of an individual in terms of their employment, education, social life, etc.
to determine how changes in brain function might impact the individual's overall well-being on a daily basis
to aid in diagnosing whether observed changes are due to a neurological condition or organic brain function syndrome (e.g., dementia from Alzheimer's disease, brain injury, stroke, a developmental problem, or a psychiatric condition)
to observe changes in a patient's behavior over time to determine a prognosis, or to anticipate therapies that should be administered (e.g., to monitor the progress of a stroke patient and determine the effect of physical therapy on their rehabilitation)
to determine if the patient's prognosis may be enhanced through neurosurgical intervention (e.g., surgery to reduce frequency of seizures in an epileptic patient)
to discern if a patient has the potential to be rehabilitated and what compensatory therapy might be beneficial
to provide information that will assist family members and caregivers in helping the patient once the patient has been discharged and returns home

Precautions

Several factors may impact neuropsychological testing results. Age and sex of the individual must be considered, as children and older adults may respond differently than young or middle-aged adults to a setting and to certain types of questions, and males may respond differently than females. The patient's personality may also affect performance on these tests based on the individual's motivation, self-esteem, and attitude toward the testing sessions. Additionally, the educational, social, and cultural background of the patient must be considered. For example, individuals may have difficulty comprehending what is being asked of them or difficulty performing certain tasks if they are not a native speaker of the language in which the tests are administered. For some individuals, the act of undergoing such testing arouses anxiety, which may influence test results.

Some neurological testing sessions are lengthy, and it may be difficult for some individuals to maintain focus and concentration throughout the entire session if they are in pain, depressed, anxious, or sleep deprived. The extent of prior exposure to previous testing sessions may also play a role how an individual performs on the tests. Some individuals may become adept at responding to a test if it has been administered several times. This can give a false representation of improvement. Also, standardized testing is based upon comparison to a set of "normal" data, but data from some groups, such as those with diminished cognitive capacity, may not be included in the "normal" data used for comparison. As a result, it may be difficult to accurately assess a problem in function for such individuals.

It is critical that a thorough physical assessment be performed to help determine if a clinical presentation is due to a psychiatric problem, physical problem, or a combination of both, since there can be complex interactions and overlap between psychological and physiological conditions. Also, physical problems may inadvertently influence a testing session (e.g., a vision or hearing problem may result in slow or inaccurate responses).

Taking a detailed medical and psychological history from the patient is an essential part of the neuropsychological testing process. Additional information about may be obtained from others who know the patient well, such as family members or caregivers. These individuals may be able to give the clinician a more accurate portrait of consistent patterns in behavior than can be detected in a more structured clinical testing session. Additionally, their input may bring to light aspects of the patient's condition that need follow-up for rehabilitation to improve effective daily functioning.

It may be necessary to administer more than one type of test in order to gather enough data to draw a clinical conclusion, thus patients may need to return for multiple testing sessions. Also, the presence of a rare condition may be difficult to pinpoint without extensive testing because tests generally are designed to evaluate more common conditions. Testing can be quite comprehensive, and include psychological as well as physical assessments that incorporate conventional laboratory analysis and the use of neuroimaging techniques, such as magnetic resonance imaging (MRI) and positron emission tomography (PET) scans. Diagnosis is usually accomplished by combining various testing methods to define the condition from both physiological and psychological perspectives.

Description

One of the first steps taken during a neuropsychological assessment is a thorough examination of clinical notes by healthcare providers that detail the nature of the condition. The healthcare team is then challenged to determine the level at which the patient was functioning prior to the onset of the condition that is being evaluated.

The testing setting must be conducive to optimal performance for the patient. Often, the test is performed in a quiet room designed to minimize distractions and put the patient at ease. The duration of testing depends upon the type of tests and the capacity of the patient to undergo multiple testing sessions. Often, to establish consistency of testing conditions, multiple tests are performed in one day.

The types of tests administered vary with the condition of the patient. Sometimes, a battery of tests is administered as a panel in order to attempt to address the majority of cognitive functions. Such tests may be long, however, and lack the detail needed for full clinical assessment. Another approach involves the initial step of generating a hypothesis about the condition and then administering only those tests that test this hypothesis. However, with this approach more subtle problems may be overlooked.

Pre-morbid levels of function

It is important to assess the level of function before the current condition developed (pre-morbid functioning) through past history information, as each person initially has his or her own baseline "normal" level of functioning. For example, those individuals who initially functioned at a very high level may have a significant impairment, yet test within normal results when compared to standardized testing norms.

In order to assess pre-morbid functioning, the patient, the family, and prior caregivers are often interviewed. During this interview, questioning revolves around identification of the problem, severity of symptoms and their onset, and the impact of the condition on the patient's daily functioning. Patients often have difficulty recalling information in a structured, unfamiliar setting that could be anxiety provoking. Therefore, they may be presented with lists that describes symptoms and problems and asked them to check those that they experience. Family members and caregivers should be interviewed separately from the patient, as they may not feel comfortable describing sensitive issues in the patient's presence, and the patient may not wish to disclose the true nature of his or her situation. In addition to a medical history, questions may be asked about the patient's cultural, educational, social, vocational, and emotional history. This provides clinicians a backdrop of a person's life used to frame the results obtained from testing. Throughout the process, the patient's behavior will be observed to gain insight into aspects such as their alertness, motivation to cooperate, attention span, affect, ability to remember, ability to speak, and level of anxiety.

In addition to gathering historical information from the patient, family, and caregivers, a variety of tests may be used to help determine of the level of pre-morbid function. The National Adult Reading Test-2 (NART-2) and North American Adult Reading Test (NAART) assess the individual's ability to read words with unusual spellings. The Wechsler Test of Adult Reading (WTAR) tests the reading level of words with unusual pronunciations. Word recognition and vocabulary, considered by some to remain fairly constant throughout brain damaged conditions, can be assessed by the Shipley Institute of Living Scale (SILS), a vocabulary test that involves word recognition. However, there is a wide range of abilities for this skill in normal individuals. Wide Range Achievement Test-Revision 3-Reading (WRAT3) tests the verbal ability of patients to read a series of words of increasing complexity. The Speed and Capacity of Language Processing Test (SCOLP) tests the ability to process language quickly.

Assessment test groups

Once an estimation of pre-morbid functioning has been made, further testing can be performed to assess current functioning in a wide variety of areas. Some of the areas that can be tested include attention, intelligence, influences of personality and emotions, learning and memory, executive functions, language and communication functions, and visual and construction functions.

ATTENTION. Attention testing involves assessment of the ability to quickly process information and the use of memory by examining the ability to focus and sustain attention, despite distraction, the ability to manipulate information, and the ability to visually search for information. Some of the tests for assessment of attention include Digit Span (repeating a series of digits in their proper order as well as backwards), the Vigil Continuous Performance Test (computerized testing), the Brief Test of Attention (BTA, discerning letters from numbers in a list and vice versa), and the Connor's Continuous Performance Test-II (CPT-II, visual attention).

INTELLIGENCE. Intelligence tests determine the overall ability to perform certain tasks, and assist the clinician in estimating where the patient's abilities fall as compared to the norm. Some common tests of intelligence include the Wechsler Scales (verbal and performance IQ, specific for children and adults), the Kaufman Adolescent and Adult Intelligence Test (KAIT, measures IQ and problem solving), Raven's Progressive Matrices (reasoning using designs and patterns, tests specific for children and adults), the Stanford-Binet Intelligence Scale (SB-IS, measuring different tiers of cognitive abilities), and Bayley Scales II (used in very young children to test the development of motor and cognitive skills).

INFLUENCES OF THE PERSONALITY AND EMOTIONS. Emotions and personality may have a profound impact on the results of neuropsychological tests. In patients with brain injury, the areas of the brain that regulate emotional control may be damaged. Additionally, there may be emotional changes and reactions as a result of coping with the condition and its subsequent effects on daily life. A variety of tests may be used to detect conditions such as underlying depression, an anxiety disorder, or hyperactivity. Some common tests include the Minnesota Multiphasic Personality Inventory (MMPI-2), the Beck Depression Inventory (BDI-II), the Personality Assessment Inventory (covers items such as mental disorders and drug and alcohol problems), and the Neuropsychological Impairment Scale.

LEARNING AND MEMORY. Memory problems are often one of the first signs of dysfunction in certain diseases such as Alzheimer's and Parkinson's disease. Testing memory and learning often requires multiple tests administered over time to determine disease progression or to monitor rehabilitation efforts. A variety of tests are used to assess different aspects of both verbal and nonverbal information, and how information is retained, recalled, and forgotten. Some of the tests used to assess memory and learning include the Neurobehavioral Functioning Inventory (with two parts, one for the patient and one for the family to complete regarding the patient), Memory Assessment Scales (MAS, test memory of both verbal and visual cues), Wechsler Memory Scale III (WMSIII, a comprehensive test with different scores for different types of memory), and the California Verbal Learning Test (information about how the memory is acquired, retained, and recalled).

EXECUTIVE FUNCTIONS. Executive functions are exhibited when an indiviudal is in an unfamiliar situation and he or she must develop a new behavior or thought process in order to carry out an activity. Executive functions include abstract thought processes, establishing a goal and planning how to achieve it, and introspection. Loss of such function may have social impacts, such as aggressiveness, apathy, and failure to acknowledge social norms. Some tests to evaluate executive functions include the Stroop Color and Word Test, Trail Making Test (measures the ability to visually scan and to maintain one's visual attention), and the Wisconsin Card Sorting Test (a test of abstract reasoning that requires individuals to sort cards based on categories).

LANGUAGE AND COMMUNICATION FUNCTIONS. It is necessary to assess a patient's capacity to speak and communicate because a deficiency in either of these areas may negatively impact the individual's score on other neuropsychological tests. Language and communication skills are observed by the clinician during the testing process, but additional testing may be necessary if a deficiency is suspected. The Boston Diagnostic Aphasia Examination (BDAE-III) is a common test of language and communication skills. This test measures the ability to produce speech spontaneously and comprehend written material. It measures aphasia, a difficulty with the ability to recall words that arises from brain pathology. The Frenchay Dysarthria Assessment is often used to evaluate dysarthria, which is a difficulty in producing speech. Other specialized language and communication tests may be administered by speech and language pathologists.

VISUAL AND CONSTRUCTION FUNCTIONS. Following brain injury or in certain diseases such as Alzheimer's disease, the brain may have a reduced capacity to process visual information. Problems may relate to locating objects spatially, moving the eyes to locate an object, pointing toward a particular object, or reaching for objects on command. In addition to a vision examination by an optometrist or ophthalmologist, individuals may be assessed for the ability to point to objects, their acuity of depth perception, and their ability to estimate the size of objects. Some visual tests include the Visual-Perceptual Skills test (TVPS-R, comprehensive test for children), the Cube Analysis test (tests the patient's ability to recognize three-dimensional cubes when they are drawn in two dimensions on paper), and the Judgment of Line Orientation test.

In addition to the tests mentioned above, there exist a wide variety of specialized tests to evaluate reading and writing disorders, voluntary movement, calculation disorders, and problems with awareness. Some common test batteries covering some of these areas include the Halstead-Reitan Neuropsychological Battery, the Luria-Nebraska Neuropsychological Battery, and the Boston Process Approach.

Preparation

The accuracy of neuropsychological testing is highly dependent on a thorough presentation of accurate past medical and psychological history, as well as observations of the patient, the family, and the caregivers. As such, it is important for the clinician to be provided with copies of the patient's medical records, past evaluations, list of medications, and information related to the onset and progression of symptoms of the condition to be evaluated. The patient and family should be willing to discuss sensitive areas such as alcohol and drug use, suicide attempts, and problems in the home that may exist as a result of the condition. If the individual has been involved in an accident that resulted in brain damage, any copies of emergency room records may assist in evaluating pre-morbid functioning, as would past records of scholastic performance, such as academic transcripts or standardized test scores. Employment history and description of job functions is also useful for evaluating pre-morbid functioning.

In some cases, information about complications that the patient's mother had during pregnancy, childhood illnesses, developmental milestones, and previous behavioral or psychological problems may be useful to the clinician. In summary, successful evaluation of neuropsychological testing results requires open and honest communication between the clinician, patient, family, and caregivers to gather as much data as possible to assist with accurate characterization of the patient's past functioning and present condition.

Aftercare

For some patients, undergoing neuropsychological testing may be exhausting and stressful, producing an anxiety response. Information gained from testing may be depressing for individuals if they receive an unfavorable diagnosis. Care should be taken in presenting the results of the tests clearly and compassionately. Counseling for the family and/or the patient may be recommended.

Results

The results from neuropsychological testing must be carefully interpreted within the context of the physiological and psychological state of the individual, as well as his/her cultural, educational, and vocational background. Additional testing may be required to periodically monitor the individual's prognosis or assist in the effort toward rehabilitation. In some cases, the patient can be taught compensatory strategies for dealing with the challenges of the condition in daily life.

KEY TERMS

Neuroimaging— The use of imaging tools such as contrast MRI and PET scans to examine brain anatomy and function in a non-invasive way.

Neuropsychological assessment— A series of tests in a controlled setting that help to assess brain function in the areas of cognition, emotional health, and behavior.

Neuropsychological test battery— A defined group of neuropsychological tests that are administered collectively to an individual to assess their level of function.

Pre-morbid function— A measure of the individual's baseline level of functioning at his/her best performance level. Characterization of this level is usually drawn from history of past performance and information from the personal, educational, and vocational history.

Healthcare team roles

Clinicians (neuropsychologists) and administrators of the testing session

Neuropsychological testing is a complicated process influenced by many external variables. Testing data must be evaluated in the context of the patient's history, background, and capabilities to maximally respond under the testing conditions. A few practical guidelines are:

Strive to put the patient at ease in a testing environment that is conducive to maximal patient response, as free as possible from external distractions.
Establish rapport and be observant for non-verbal cues.
Be flexible in the testing session to accommodate the patient's level of performance, but do not alter the standardized test questions. Adhere to the wording in the questions to get an accurate assessment of the patient's ability to understand basic instructions.
Investigate past history thoroughly to gain an accurate understanding of the pre-morbid state.
Select tests that are appropriate to the individual's age, cultural background, educational background, and other external factors.
If elderly patients are to be tested, choose tests of shorter duration. Take care to administer appropriate tests designed for children or those who may have impairments of some type.
Be cognizant of how the results of the testing may affect the patient, family, and caregivers.
Discuss possibilities for rehabilitation and daily coping strategies.

Nurses

The assessment process is quite comprehensive, requiring nurses to assist as part of the healthcare team. There are several practical considerations that can aid in communication between the nurse and the patient during the evaluation and rehabilitation process: they are primarily centered on developing a non-threatening rapport with the patient and establishing good communication. These elements are essential to the success of the assessment, care, and rehabilitation of the individual. Several, practical ways that nurses can assist in the assessment process are:

Develop rapport by making eye contact, calling the patient by name, and being respectful. In general, strive to put the patient at ease.
Demonstrate sensitivity to physical needs by speaking clearly and adjusting the volume of speech for those who are hearing impaired or adjusting the lighting for individuals with vision problems. Make sure that the patient is as comfortable as possible.
Ask questions so as to allow the patient an opportunity to express his or her feelings and concerns. Try to understand the patient's perspective and struggle to cope with problems and challenges the patient faces in performing daily activities.
Try to determine what kind of support is needed by the patient.
Allow patients to establish some measure of control and self-esteem by inquiring about their preferences regarding daily activities and how they would like to schedule them.
Help patients establish goals that are obtainable for them. For those who may be more anxious in situations that require decision-making, reduce their choices to just a few options from which to choose. Be patient and supportive of small steps that they make to achieve their goals.
Educate the patient on as many aspects of the condition as possible.