The Mental Status Examination
– Mental Status Examination and Higher Cortical Functions > Chapter
5 – The Mental Status Examination
examination is used to help determine if a patient has neurologic as
opposed to psychiatric disease, to identify psychiatric disease which
might be related to underlying neurologic disease, and to distinguish
focal neurologic deficits from diffuse processes. Abnormalities of
mental status could be due to a focal frontal lobe lesion such as a
stroke or tumor, to diffuse disease such as metabolic encephalopathy,
or to a degenerative process such as Alzheimer disease. Patients might
have separate or comorbid psychiatric illness causing neurologic
symptomatology, or psychiatric illness related to underlying neurologic
disease, such as post stroke depression. The psychiatric mental status
examination is longer and more involved than the neurologic mental
status examination, as it explores elements of psychiatric function
that are not usually included in a neurologic mental evaluation. One
possible organization of the psychiatric interview and the elements of
the structured mental status examination is shown in Table 5.1. The additional elements of the psychiatric mental status are listed in Table 5.2.
may aid in evaluating his emotional status, memory, intelligence,
powers of observation, character, and personality. Observe the general
appearance, attitude, and behavior of the patient, including whether he
looks tidy, neat, and clean
or
slovenly, dirty, and rumpled. Note the patient’s manner, speech, and
posture, and look for abnormalities of facial expression. There may be
odd or unusual dress, gait, and mannerisms; prominent tattoos;
excessive jewelry; or other evidence of eccentricity. Unkempt,
disheveled patients or those dressed in multiple layers may have
dementia, frontal lobe dysfunction, a confusional state, or
schizophrenia. Depression, alcoholism, and substance abuse may lead to
evidence of self-neglect. Flamboyant dress may suggest mania or
hysteria. Patients with visuospatial disturbances or dressing apraxia
due to a nondominant parietal lesion may not be able to get into their
clothes properly.
TABLE 5.1 One Possible Organization of the Psychiatric Interview and the Mental Status Examination
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understand the situation, and be in touch with the surroundings, or
appear anxious, distracted, confused, absorbed, preoccupied, or
inattentive. The patient may be engaged, cooperative, helpful, and
pleasant or indifferent, irritable, hostile, or belligerent. He may be
alert, even hypervigilant, or dull, somnolent, or stuporous. Patients
who are disinhibited, aggressive, or overly familiar may have frontal
lobe lesions. Patients who are jumpy
and
hyperalert with autonomic hyperactivity (sweating, tachycardia) may be
in drug withdrawal. Abnormal motor activity may include restlessness;
repetitive, stereotypical movements; bizarre mannerisms; catatonia; and
posturing. Inertia and psychomotor slowing suggest depression,
dementia, or parkinsonism. Restlessness, agitation, and hyperactivity
may occur with mania or drug ingestion. Note any tendency to emotional
lability (pseudobulbar state) or apparent unconcern (la belle indifference).
The ability to establish rapport with the patient may give insight into
the personality of both the patient and the physician. It is sometimes
informative to observe patients when they are not aware of being
watched.
TABLE 5.2 Elements of the Psychiatric Mental Status Interview
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interaction with the patient during the history taking phase of the
encounter, then a more formal mental status examination (MSE) should be
carried out. The formal MSE is a more structured process that expands
on the information from the history. Detailed MSE should also be
carried out if there is any complaint from the patient or family of
memory difficulties, cognitive slippage, or a change in character,
behavior, personality, or habits. For instance, formerly personable and
affable patients who have become irascible and contentious may have
early dementia. Other reasons to proceed further include symptoms that
are vague and circumstantial, patients with known or suspected
psychiatric disease or substance abuse, or when other aspects of the
neurologic investigation indicate subtle or covert cognitive impairment
could be present, such as anosmia suggesting a frontal lobe tumor.
instruments have been developed for use at the bedside and in the
clinic. The most widely used of these is the Folstein Mini-Mental State
exam (MMSE), but there are others, including the
Information-Memory-Concentration Test, Orientation-Memory-Concentration
Test, Mental Status Questionnaire, Short Portable Mental Status
Questionnaire (SPMSQ), Abbreviated Mental Test (AMT), Neurobehavioral
Cognitive Status Examination, Short Test of Mental Status, Cambridge
Cognitive Examination, and Cognistat (Table 5.3).
The MMSE has a series of scored questions that provides a localization
based overview of cognitive function, but does not assess any function
in detail. The maximum score is 30. Minimum normal performance depends
on age and educational level, but has been variously stated as between
24 and 27 (Table 5.4). The MMSE has limitations
in both sensitivity and specificity, and should not be used as more
than a screening instrument. It is affected not only by age and
education, but by gender and cultural background. With a cutoff score
of 24 the test is insensitive and will not detect mild cognitive
impairment, especially in well educated or high functioning patients. A
normal MMSE score does not reliably exclude dementia. There is also a
relatively high false positive rate. A comparison of the MMSE, AMT, and
SPMSQ showed sensitivities of 80%, 77%, and 70% and specificities of
98%, 90%, and 89%, respectively. In patients where there is a question
of
cognitive
impairment or a change in behavior and the MMSE or a similar instrument
is normal, formal neuropsychological testing may provide more detail
regarding the mental status.
TABLE 5.3 The Short Orientation-Memory-Concentration Test for Cognitive Impairment
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TABLE 5.4 The Mean (Standard Deviation) Mini-Mental State Examination Scores Based on Age and Educational Level
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status, especially memory, the examiner should assure that the patient
is alert, cooperative, attentive, and has no language impairment.
Mental status cannot be adequately evaluated in a patient who is not
alert or is aphasic. To avoid upsetting the patient, it is desirable,
when possible, to examine the mental functions unobtrusively by asking
questions that gently probe memory, intelligence, and other important
functions without appearing to conduct an inquisition.
an assessment of orientation. Normally, patients are said to be
“oriented times three” if they know who they are, their location, and
the date. Some examiners assess insight or the awareness of the
situation as a fourth dimension of orientation. The details of
orientation are sometimes telling. The patient may know the day of the
week, but not the year. Orientation can be explored further when
necessary by increasing or decreasing the difficulty level of the
questions. Patients may know the season of the year if not the exact
month; conversely, they may be oriented well enough to know their exact
location down to the street address, hospital floor, and room number.
Most patients can estimate the time within half an hour. Orientation
questions can be used as a memory test for patients who are
disoriented. If the patient is disoriented to time and place, they may
be told the day, the month, the year, the city, etc., and implored to
try to remember the information. Failure to remember this information
by a patient who is attentive and has registered it suggests a severe
memory deficit. Occasional patients cannot remember very basic
information, such as the year, the city, or the name of the hospital,
despite being repeatedly told, for more than a few seconds. In the
presence of disease, orientation to time is impaired first, then
orientation to place; only rarely is there disorientation to person.
function cannot be attributed to cortical dysfunction if the patient is
not attentive to the tasks. Defective attention taints all subsequent
testing. Patients may appear grossly alert but are actually
inattentive, distractable, and unable to concentrate. An early
manifestation of toxic or metabolic encephalopathy is often a lack of
attention and concentration in an apparently alert patient, which may
progress to delirium or a confusional state. Confusion, inattention,
and poor concentration may also be seen with frontal lobe dysfunction,
posterior nondominant hemisphere lesions, and increased intracranial
pressure. Lesions causing apathy or abulia also impair attention.
Patients with dementing illnesses are not typically inattentive until
the
cognitive deficits are severe. The possibility of a CNS toxic or
metabolic disturbance should be considered when the patient is
inattentive.
heard from a string of random letters dictated by the examiner, or
having the patient cross out all the A’s on a written sheet may reveal
a lack of attention or task impersistence. In the line cancellation
test, the patient is requested to bisect several lines randomly placed
on a page. Inattentive, distractable patients may fail to complete the
task. Patients with hemineglect may bisect all the lines off center, or
ignore the lines on one side of the page.
concentration, and immediate memory. The examiner gives the patient a
series of numbers of increasing length, beginning with 3 or 4, at a
rate of about one per second, and the patient is asked to repeat them.
The numbers should be random, not following any identifiable pattern,
e.g., a phone number. Backward digit span, having the patient repeat a
series of numbers in reverse order, is a more complex mental process
that requires the ability to retain and manipulate the string of
numbers. Expected performance is 7 ± 2 forward and 5 ± 1 backward.
Reverse digit span should not be more than two digits fewer than the
forward span. Forward digit span is also a test of repetition and may
be impaired in aphasic patients. Another test of attention and
concentration is a three step task. For instance, tear a piece of paper
in half, then tear half of it in half and half in half again, so that
there are three different sizes. Give the patient an instruction such
as “give the large piece of paper to me, put the small piece on the
bed, and you keep the other piece.” Another multistep task might be,
“stand up, face the door, and hold out your arms.”
patients may fail to attend to one side of space (hemi-inattention or
hemineglect). The nondominant (usually right) hemisphere has special
responsibilities regarding attention. It seems to maintain attention in
both right and left hemispace. The dominant hemisphere in contrast only
attends to contralateral hemispace. Patients with right parietal
lesions often have hemineglect for the left side of space. They may
also ignore even a profound neurologic deficit involving the left side
of the body (anosognosia). With dominant lesions, the nondominant
hemisphere can attend well enough to both sides of space that
hemineglect does not occur as a prominent feature. Bilateral lesions
may be required to cause neglect of right hemispace. Neglect may also
occur with thalamic lesions.
function that requires the patient not only to attend to a complex task
but to marshal other intellectual resources, such as the ability to
mentally manipulate items. Tests of mental control include serial 7’s
or 3’s, spelling world backwards (part of
MMSE), and saying the days of the week or months of the year in
reverse. Most normal adults can recite the months of the year backwards
in less than 30 seconds. When underlying functions, e.g., calculation
ability, are intact, defective mental control may indicate dorsolateral
frontal lobe (executive) dysfunction, usually on the left.
ways. Memory terminology is not used consistently, and a precise
description of the task attempted is often more useful than describing
the patient’s “recent memory.” A commonly used memory classification
includes immediate (working memory), recent (short-term), and remote
(long-term). Digit span is a test of attention and immediate memory, a
very short term function in which the material is not actually
committed to memory. A patient’s fund of information reflects their
remote memory. The fund of information includes basic school facts,
such as state capitals, famous presidents, and important dates, as well
as current information such as the sitting president, vice-president,
governor, and similar public officials. The patient should also know
personal information, such as their address, phone number, social
security number, wedding anniversary date, and names of children.
Mothers and grandmothers usually know the ages and birth dates of their
children and grandchildren. These items are fertile ground for
assessing remote memory and fund of information so long as there is
some
way to check the accuracy of responses. Judging the expected fund of
information for patients with low educational attainment is often
difficult, but any normal patient should be fluent with their personal
information (except for the phone number, which many do not know,
saying “I never call myself”). Asking directions is often useful, and
tests both memory and spatial ability. Most patients are able to
describe how to drive from their home to the place of the encounter, as
well as the general direction and distance to major cities and local
towns. Patients who work in very specialized fields and who have few
outside interests are challenging to assess. Patients with major
cognitive impairment may still recall some deeply ingrained,
overlearned memories, e.g., days of the week, months of the year,
nursery rhymes, and jingles.
patient items to recall. The recall items may be simple objects, such
as orange, umbrella, and automobile, or more complex, such as “John
Brown, 42 Market St., Chicago.” The items should be in different
categories. After ensuring the patient has registered the items,
proceed with other testing, and after approximately 5 minutes ask the
patient to recall the items. Patients with severe memory deficits may
not only fail to recall the items, they may fail to recall being asked
to recall. Some patients may fail to remember the items, but can
improve performance with hints or pick the items from a list. A
distinction is made between retention and retrieval. Patients who are
able to remember items with cueing or by picking from a list are able
to retain the information, but not retrieve it. When cueing or picking
do not improve performance, the defect is in retention. Patients with
early dementing processes may have only a failure of retrieval. Another
memory test is to ask the patient to remember the Babcock sentence
(“One thing a nation must have to be rich and great is a large, secure
supply of wood.”) after 5 minutes. Normal patients can do this in three
attempts. Tests of nonverbal memory include hiding objects in the
patient’s room as they watch, then having them remember where the
objects are hidden, or asking them to remember shapes, colors, or
figures.
asking the patient to count forward or backward, to count coins, or to
make change. Dyscalculia is characteristic of lesions of the dominant
parietal lobe, particularly the angular gyrus. Patients may be asked to
select a certain amount from a handful of change presented by the
examiner. Calculations may be more formally tested by having the
patient perform simple arithmetic, mentally or on paper. The ability to
calculate depends on the patient’s native intelligence, their innate
number sense or mathematical ability, and educational level. Basic
calculations, such as 2 + 2, are often rote, overlearned items from
early schooling, and these test remote memory more than calculating
ability. The average normal patient can perform mental calculations
that involve two digit operations and require simple carrying and
borrowing. If successful initially with very simple calculations, the
patient should be pressed to at least a moderate level of difficulty,
e.g., 12 × 13, 17 + 11, 26 + 14. Another test is to ask the patient to
sequentially double a number until failure. Asking the patient to add
or subtract a column of two or three digit numbers on paper further
requires them to correctly align and manipulate a column of numbers and
gives insight not only into calculating skill, but into their
visuospatial ability, which may be particularly impaired with
nondominant parietal lesions. Simple mathematical problems may be
presented, e.g., if apples are a quarter apiece, how many can you buy
for a dollar? how many quarters are in $1.50? if a loaf of bread cost
89 cents and you paid with a dollar, what change would you get back? A
commonly used calculation task is subtracting serial 7’s from 100
(failing that, serial 3’s). This function also requires attention and
concentration. Counting to 20 is more of a remote memory test and
counting backward from 20 more of an attentional task. There is little
difference in calculating ability across age groups, and little
impairment in early Alzheimer disease, but advancing disease
dramatically alters calculation ability.
because they make paraphasic errors involving the numbers. Impaired
calculating ability may occur with posterior dominant hemisphere
lesions,
either as an isolated defect or as part of Gerstmann syndrome. These
patients have a true anarithmetria, a primary disturbance of
calculating ability.
asking the patient to describe similarities and differences and to
interpret proverbs and aphorisms. The patient may be asked what is
alike about an apple and a banana, a car and an airplane, a watch and a
ruler, or a poem and a statue; or to tell the difference between a lie
and a mistake, between laziness and idleness, or between a cable and a
chain. The patient may be unable to interpret a proverb, or may
interpret it concretely or literally. For “Don’t cry over spilt milk,”
the patient thinking concretely will talk about accidents, milk,
spillage, cleanup, and other things which miss the point. The
usefulness of proverb interpretation has been questioned. It seems many
examiners are not precisely sure themselves what some of the proverbs
mean. Some commonly used proverbs include: a rolling stone gathers no
moss, a stitch in time saves nine, Rome wasn’t built in a day, and
people who live in glass houses shouldn’t throw stones. Bizarre,
peculiar proverb interpretations may be given by patients with
psychiatric disease, or normal people not familiar with the idiomatic
usage. It may be useful to throw in a concatenated, mixed, and confused
proverb or saying such as “the hand that rocks the cradle shouldn’t
throw stones,” to test both the patient’s abstraction ability and sense
of humor. Impaired abstraction occurs in many conditions, but is
particularly common with frontal lobe disorders.
the patient what they would do if they found a sealed, addressed,
stamped letter on the sidewalk, or smelled smoke in a crowded theater
may be less useful than determining if the patient has insight into his
illness and the implications of any functional impairment. Historical
information from family members about the patient’s actual judgment in
real life situations may be more enlightening than these artificial
constructs. Patients with no concern about their illness have impaired
judgment. Patients with poor judgment may behave impulsively or
inappropriately during the examination. Many neurologic conditions may
impair judgment, particularly processes that affect the orbitofrontal
regions. Lack of insight into the illness, to the point of denial of
any disability, may occur with nondominant parietal lesions.
methods of bedside testing, including formal neuropsychological
assessment, may fail to detect even significant frontal lobe
dysfunction. Comparison with the patient’s premorbid personality and
behavior are often more telling than assessment based on population
derived reference information. In addition to the standard tests of
abstract thinking and proverb interpretation, special techniques
designed to evaluate frontal lobe function may be useful. Tests helpful
for evaluating frontal lobe function include verbal fluency by word
list generation, assessment of the ability to alternate tasks or switch
between tests, abstraction ability, and tests for perseveration,
apathy, and impulsivity,
methods may not be able to generate word lists. The Wisconsin Card Sort
test is used by neuropsychologists to determine if the patient can
shift between tasks (shift sets). The formal test requires the patient
to discover through trial and error the expected sorting of cards by
color, shape, or number, then to recognize and adapt to a change in the
scheme. A bedside variation is to ask the patient to detect a pattern
when the examiner switches a coin between hands behind his back, e.g.,
twice in the right hand, once in the left, then to change the pattern
and see if the patient detects the new scheme. Perseveration is the
abnormal, inappropriate repetition of words or actions. Patients with
frontal lesions, especially those involving the dominant dorsolateral
prefrontal cortex, have difficulty abandoning the
initial
pattern of responses, and tend to perseverate. In trail making tests
the patient is required to connect in sequence either letters or
numbers scattered around a page (Trails A), or to alternate connecting
letters and numbers, e.g., A-1-B-2-C-3 (Trails B). In another test of
alternating ability, the patient writes a string of M’s and N’s, all
connected. In Luria’s fist-edge-palm test, the patient is asked to
repetitively place the hand down in a series of motions: fist, edge of
hand, palm, over and over. There is a tendency to perseveration and
difficulty accurately executing the sequences of hand positions,
particularly with frontal lobe lesions. In copying tasks involving
drawing simple figures with multiple loops, patients with perseveration
may insert extra loops.
inhibit automatic responses. In the “little-big” test the words little
and big are printed on separate cards in both upper and lower case
letters, and the patient required to respond aloud “big” if the print
is upper case, even in response to the word “little,” or vice versa. A
variation is to write several color names in nonmatching colors, e.g.,
write the word blue with a red marker, then ask the patient to read the
cards by stating the color of the print not the written name of the
color. Patients with frontal lobe dysfunction have trouble inhibiting
the tendency to read the color name. The antisaccade task is another
measure of the ability to inhibit automatic responses.
“imitation behavior” in patients with frontal lobe damage. Patients
with utilization behavior will reach out and use objects in the
environment in an automatic manner, and are not able to inhibit this
response. Similarly, patients with imitation behavior will imitate the
examiner’s gestures, even if specifically told to refrain.
include assessment of visuospatial and constructional ability, praxis,
language disturbances, recognition (visual, tactile, and auditory),
rightleft orientation, and finger identification. These are discussed
in subsequent chapters.