The patient’s appearance and general behavior are important indicators of his or her general level of function. The well-dressed, well- organized patient is likely functioning at a higher level than the disheveled, unkempt patient. Additionally, a patient’s dress and demeanor are important indicators of underlying psychiatric and psychological disturbances, such as the patient who is inappropriately dressed for the weather or is clearly responding to unseen stimuli.

Level of consciousness is a crucial part of the mental status examination. One should note and document whether the patient is awake, alert, and attentive versus unresponsive or drowsy. A lethargic patient appears drowsy but is easily aroused. An obtunded patient has a reduced level of consciousness and cannot easily be aroused. An unconscious patient who cannot be fully aroused is stuporous. An unconscious patient with no purposeful response to even noxious stimuli is comatose.

Mood refers to a person’s persistent emotional state, while affect denotes more immediacy. Mood and affect can be assessed by observing the patient’s body language and behavior as well as by verbal report. Depression is a state of persistently low mood. A brief screen for depression includes inquiries about reduced “spirits,” reduced energy, poor self-attitude, poor appetite, disturbed sleep, anhedonia, thinking difficulty, suicidal ideation, and psychomotor retardation. Conversely, mania is a state of persistently elevated mood, increased energy, and heightened self-attitude, sometimes in association with delusions of grandeur, pressured speech, and “flight of ideas.” Depression is seen in a number of neurologic disorders including Parkinson disease, Huntington disease, and strokes affecting the dominant hemisphere; mania may be seen occasionally with cerebral lesions of the nondominant hemisphere.

Speech refers to the articulation of words, while language deals more with the structure and meaning of the spoken and written word. Both provide the examiner valuable insight into the patient’s mental state and can be assessed easily during the interview. Important aspects of speech include the amplitude or loudness, volume or amount (paucity vs. overabundance), and prosody or fluidity. Often patients with end-stage dementia will have paucity of speech. Patients with Parkinson disease will often have hypophonic or soft speech. Patients with cerebellar disorders may speak in a “choppy” ataxic manner. Speech may be slurred or dysarthric in a number of different clinical settings.

A patient’s language capabilities can be assessed quickly by evaluating spontaneous speech and comparing it to comprehension of spoken and written material. The presence of a language disturbance or aphasia should be identified early, as it may preclude an adequate assessment of the rest of the mental status examination. An aphasia may be expressive or receptive. An expressive or nonfluent aphasia (e.g., Broca aphasia) is characterized by difficulty producing speech with intact comprehension, and typically results from lesions in the inferior frontal region of the dominant (usually left) hemisphere. In contrast, a receptive or fluent aphasia (e.g., Wernicke aphasia) is characterized by poor comprehension without difficulty producing speech. This may result in the production of nonsensical speech (“word salad”) and is typically caused by lesions of the posterior temporal area of the dominant hemisphere.

Additonal localizing information can be gleaned by assessing the patient’s ability to repeat and write.

Two components of memory are commonly assessed-working memory (also known as primary memory) and long-term memory (also known as secondary memory).

Working memory is assessed by measuring digit span (most patients can repeat strings of approximately seven digits) or by backward spelling (“Please spell WORLD backward.”), which are commonly interpreted as tests of attention.

Long-term memory is typically tested using delayed word recall. Patients are given a list of three to five words (e.g., “cat, table, apple, purple, and bank”) and asked to repeat them back (registration). After being distracted by other tasks (such as tests of working memory or visuospatial processing), the patient is asked to recall the list of words (retrieval). Clues or cues may be given (e.g., “One of the words was an animal,” or “One of the words began with the letter C.”). Difficulty with this type of delayed recall can be seen with lesions of the temporal lobe or thalami affecting the hippocampi or other structures within the Papez loop. The distinction between “recent long-term memory” (e.g., “What you had for breakfast this morning?”) versus “remote long-term memory” (e.g., an event from childhood) is somewhat artificial. The use of the term short-term memory may be confusing as some use it to refer to working memory, while others use it to refer to recent long-term memory (see Chapter 15, Behavioral Neurology).

Common tests of visuospatial processing include copying a complex figure or clock drawing. Patients can be asked to copy a design drawn by the examiner (e.g., a drawing of a cube, intersecting pentagons, or the façade of a house), or they may be asked to draw a clock face set to a particular time (e.g., “twenty after eight”). Patients with parietal dysfunction may neglect to draw half of the figure or may have trouble placing the numbers correctly on the clock face.

The integrity of the frontal lobes may be tested in several ways. Poor performance on tests of executive function, poor judgment and insight, or the presence of frontal release signs may all be evidence of frontal lobe impairment.

Some simple tests of executive function include assessment of verbal fluency and oral trail making. To assess verbal fluency, patients should be asked to generate a list of words from a specific category (e.g., “words that begin with the letter F” or “all of the animals you can think of”) in 1 minute. Although normative values vary based on age and level of education, most patients should be able to generate 10 or more items for each list without much difficulty. Oral trail making involves having the patient sequentially alternate between letters and numbers (“A—1—B—2—C—3—etc.”). Patients with frontal lobe dysfunction
may perform poorly on these tests while doing surprisingly well on other components of the cognitive examination.

A person’s judgment relies on the value system, making an assessment of judgment the most subjective component of the mental status examination. Clinicians may ask questions such as “What would you do if you found a stamped envelope lying on the ground?” with the expected answer being, “Place the envelope in a mailbox.” Such questioning is probably most helpful in the patient who is demented or cognitively impaired. Insight refers to the patient’s understanding of his or her condition. The patient with Alzheimer disease, for example, may have little awareness of memory loss, often denying any problems in thinking.

When the frontal lobes are damaged due to trauma, tumor, stroke, or dementia, primitive reflexes may resurface. For example, the presence of a palmar grasp reflex (reflexive gripping of a finger or object stroking the palm) may signify a lesion of the contralateral frontal lobe. An abnormal glabellar reflex (persistent blinking in response to tapping of the forehead) can be noted in the setting of frontal lobe injury, although it may also be present in parkinsonian disorders. Other frontal release signs include the palmomental reflex (a twitch of the corner of the mouth when the ipsilateral palm is stroked), rooting (turning toward the cheek when stroked), and the snout reflex (pursing of the lips when the lips are tapped lightly). The presence or absence of frontal release signs does not, however, correlate well with degree of dementia.

Patients who are psychotic or delirious often report bizarre sensory experiences such as hallucinations and illusions. Hallucinations are perceptions in the absence of stimuli. These can be elicited by asking the patient if he or she has seen (or heard) things that “weren’t really there” or “that others couldn’t see (or hear).” Illusions are misperceptions, whereby the patient mistakes an object for something else, such as a coat for an intruder. Both hallucinations and illusions can be seen in patients who are delirious or encephalopathic.

Abnormalities of thought form and content are “psychotic features” associated with delirium, dementia, schizophrenia, and severe affective disorders. Abnormalities of thought content consist of bizarre beliefs such as delusions, obsessions, compulsions, and phobias. Delusions are fixed, false, idiosyncratic beliefs tenaciously held by patients. Obsessions are intrusive, recurring thoughts that disturb patients. Similarly, compulsions are acts that patients feel compelled to perform over and over again. Lastly, phobias are irrational fears held by patients. These abnormalities of thought content can be uncovered by simply asking the patient if he or she has “any special powers,” or any strong beliefs or practices that others do not share. Paranoid delusions can be specifically detected by asking patients if “anyone is after them” or if “anyone is out to get them.”

Abnormalities of thought form consist of disordered thinking such as “thought blocking,” “loosening of associations,” and “flight of ideas.” Thought blocking is evident when patients are unable to complete their thoughts while speaking. Loosening of associations is seen when patients jump from one subject to another with little connection. Similarly, flight of ideas is manifested by patients speaking at a rapid pace, on any number of subjects, without easily identifiable connections. Detecting abnormalities of thought form involves noting the manner in which patients volunteer information or respond to questions. Responses that are clear and concise are easily distinguishable from answers that are difficult to follow.

The MMSE is a commonly used screen for abnormalities of cognition. The MMSE is a 30-point
instrument that assesses orientation, language, recall, concentration, and some visuospatial skills. Ten points are awarded for varying degrees of orientation in time and space. Three points are given for registration (correctly repeating the names of three objects). Five points are given for concentration, which is tested by having the patient spell “WORLD” backward or sequentially subtracting 7 from 100 five times (e.g., 100, 93, 86, 79, 72, 65). Three points are given for correctly naming two objects and repeating the phrase “No ifs, ands, or buts.” Three points are given for following a three-step command. Three points are given for reading and enacting the sentence “close your eyes,” writing a sentence, and copying a figure composed of two interlocking pentagons. Finally, three points are given for recalling the three objects mentioned for testing registration.

Other brief neuropsychological batteries have been developed which may be useful in the clinical setting, such as the Montreal Cognitive Assessment (MoCA), which includes measures of frontal lobe/executive functioning in addition to tests of memory, language, and visuospatial processing.

The olfactory nerve (cranial nerve I) is responsible for the sense of smell. CN I is not tested routinely during the screening neurologic examination, but should be assessed when patients complain of loss of smell. Olfaction is assessed by having the patient identify a fragrant substance such as coffee or cloves. A small vial of the aromatic substance is held under one nostril, while the other nostril is occluded. The patient is asked to breathe through the unobstructed nostril and identify the scent. The exercise is repeated on the other side with a different aromatic substance. Noxious substances such as ammonia or “smelling salts” should be avoided because of the concomitant stimulation of cranial nerve V, the trigeminal nerve. Although reduced olfaction may be due to advanced age, pathologic states such as head trauma, tumors affecting the base of the skull, and certain inflammatory disorders such as sarcoid should also be considered.

The optic nerve (cranial nerve II) is responsible for vision. Evaluation of the optic nerve includes examination of visual acuity, visual fields, the pupillary light reflex, and funduscopy. Visual acuity is typically tested using a wall chart or handheld “near-card.” Each eye should be tested separately with contact lenses or glasses in place (if needed).

The pupillary light reflex is checked by having the patient look into the distance while swinging a bright light from one eye to the other. Normally, both pupils react equally to light shone in either eye (the “consensual response”). A lesion of one optic nerve may result in a weaker pupillary response from one eye when compared to the other. When severe, such a relative afferent pupillary defect results in a paradoxical dilation of the pupils when light is swung from the “good eye” to the “bad eye.”

Visual fields can be easily tested in the office or at the bedside by confrontation. The patient should be asked to fixate on the examiner’s nose while covering one eye. The examiner should hold up one, two, or five fingers in each of the four quadrants of the visual field and ask the patient to count the fingers. One or multiple trials can be conducted, depending on the accuracy of the patient. The other eye should be tested in the same manner.

A visual field defect present only in one eye suggests a lesion within that eye or of the optic nerve. Visual field defects present in both eyes may suggest a lesion farther back along the visual pathway. A bitemporal hemianopia (affecting the temporal fields of both eyes) implies a lesion of the optic chiasm. Quadrantanopias, lesions of the same quadrant of both eyes (upper right, upper left, lower right, or lower left), suggest a lesion of the optic radiations. A homonymous hemianopia, a field cut involving the same side of both eyes (meaning the temporal field of one eye and the nasal field of the other eye), suggests a lesion of the contralateral optic tract or occipital cortex. With experience, additional visual field defects such as central scotomas, macular sparing, or incongruous hemianopias can be detected as well (see Chapter 26, Eye Signs in Neurologic Diagnosis).