Chapter 4
Cognitive and Neuropsychiatric History Taking and Tips on Physical Examination
The Patient Interview
The importance of establishing an accurate and detailed account of the patient’s cognitive problems and their evolution cannot be overemphasized. It is also essential to obtain an independent account from the patient’s spouse/partner or, if necessary, another family member or close friend. This applies particularly in the area of memory disorders and behavioural/personality change, where the patient is frequently unaware of his or her deficit. By the end of the interview, it should be possible to formulate a fairly accurate provisional diagnosis, or at least to delineate the areas of cognitive function requiring particular attention on examination.
Suggested structure of interview
For the full assessment of a new patient we allow an hour, which is often not long enough for a full cognitive assessment, but this should allow a working diagnosis to be reached. Further neuropsychological testing will often be necessary.
Beginning
Before embarking upon the history of the presenting complaint, it is important to establish a rapport with the patient by chatting to the patient and asking a few general, non-confrontational questions about the patient’s background, such as place of birth, schooling, past jobs, family, hobbies, and interests. Even at this stage, valuable information is gained. Clearly, if the patient is unable to engage in sensible conversation and answer simple questions accurately and coherently, then further attempts to take a history from the patient in person will be impossible and pointless. In this situation, the informant will be vital in providing information about the current problems and background.
Reason for referral
Does the patient know why he or she has been referred to the clinic, or why he or she is in hospital? In ordinary medical practice, we usually assume that patients are fully aware of the reasons for their referral. In patients suffering from cognitive deficit, this is not always the case. It is revealing to enquire why they think they are being seen. Questions need to be phrased sensitively to avoid insulting or patronizing the patient, but can usually be achieved with something along these lines: ‘I like to ask all of my patients to tell me why they think they have been referred to see me’. It is surprising how often patients think that they are being seen about a skin complaint or bad hearing!
Open-ended questioning
Continue the interview by asking general ‘open-ended’, rather than leading, questions. This provides the best opportunity to obtain a non-biased narrative account of the patient’s problems. Some suggestions are:
Try to record in the hospital notes phrases used by the patient verbatim. These are often much more meaningful and useful to future doctors than statements such as ‘complaining of memory difficulties’ or ‘six years of progressive dementia’.
Direct questions
In all cases, the narrative account obtained by open-ended questions needs to be supplemented by questions designed to probe specific domains of cognitive function. In this way, an overall pattern of abilities in each area can be built up. Valuable additional information will be obtained by questioning the patient’s relatives. Indeed, in more impaired patients this supplementary information is by far the most important. A checklist for use with patients and informants is given in Table 4.1 and expanded in the following sections.
1. Memory
The complaint ‘memory difficulty’ is used in a variety of ways by patients and relatives. Try to establish if the patient is referring to one of the following three domains.
Attention and concentration
Symptoms of poor attention include the inability to concentrate when reading a magazine or book; difficulty following conversations although language comprehension is normal; immediate loss of new information, for instance, following a telephone conversation; walking from one room to another and forgetting the reason why you wanted to go there; slips of everyday action such as putting the milk in the oven or the clean plate in the dishwasher and so on.
These are all symptoms that we all experience at times of stress, when very tired, or preoccupied. They are exaggerated in patients with depression and anxiety but are also the types of ‘memory’ symptoms that predominate in patients with frontal, subcortical, and basal ganglia pathology.
Episodic memory
More commonly, in the context of a memory clinic, the symptom of ‘poor memory’ refers to memory for personally experienced events or recently acquired information (messages, news items, shopping, conversations, etc.), in which case the deficit is one of episodic (event-based) memory.
An important distinction, clinically and neuropsychologically, is between memory for newly encountered information (anterograde memory) and memory for past personal events (retrograde memory). Usually these are affected in parallel, and to a roughly equivalent degree, for instance, in Korsakoff’s syndrome and Alzheimer’s disease. However, dissociations may occur: after closed head injury there is severe anterograde amnesia and limited retrograde; with selective damage to the hippocampus, fairly pure anterograde memory loss may occur.
In order to gain an overall impression of the severity of memory loss it is helpful to ask the patient to estimate the degree of impairment of day-to-day memory on a scale of zero (terrible, abysmal, no recall of new information) to 10 (fine for my age, as good as my friends). We ask this question of the patient and accompanying family member. Patients with organic memory loss typically give higher scores (e.g. 5 or 6) compared to their spouse (e.g. 2 or 3), whereas the opposite applies in patients with depression or anxiety, and the ‘worried well’.
Table 4.1 Checklist for interviewing patients and informants
1. Memory |
Attention and concentration |
Anterograde: recall of new episodic information in day-to-day life (for example, recalling messages and conversations, outings/trips, losing things, family news, TV programmes, etc.), repetitiveness, disorientation |
|
Retrograde: past personal and public event memory |
|
Semantic: vocabulary, memory for names, and general factual knowledge (history, geography, etc.) |
|
2. Language |
Output: word finding, grammar, word errors (paraphasias) |
Comprehension of words and grammar |
|
Reading |
|
Writing: spelling and motor components |
|
3. numerical skills |
Handling money, shopping, dealing with bills |
4. executive abilities |
Planning, organization, problem-solving, flexibility |
Hobbies, use of appliances |
|
5. visuospatial skills |
Dressing |
Constructional abilities |
|
6. neglect phenomena |
Bodily neglect |
Neglect of extrapersonal space |
|
7. visual perception |
Recognition and identification of people |
Object and colour identification |
|
8. route finding and landmark identification |
Recognition of known landmarks, ability to learn new routes |
9. Personality and social conduct |
Social conduct, empathy, egocentrism, disinhibition |
Sexual behaviour |
|
Eating, grooming, personal hygiene |
|
10. eating |
Appetite, food preference, manners |
11. Mood |
Features of depression (including sleep, libido, appetite) |
Elation and mania |
|
12. Motivation / apathy |
Mental energy, get-up-and-go, drive |
13. Anxiety or agitation |
Irritability, restlessness, autonomic symptoms |
14. Delusions and hallucinations |
Delusions of theft, infidelity, phantom boarder, Capgras delusion; visual, auditory, tactile, olfactory hallucinations |
15. Activities of daily living |
Basic (dressing, grooming, toileting) and instrumental (using appliances, phone, banking, medication, etc.) |
It is impossible to separate history taking from assessment in the context of a memory clinic so the informal chat at the beginning of the interview reveals much about remote episodic memory. Many patients with significant episodic memory problems display the ‘head turning sign’. That is to say, when asked about past life events they appear vague and say something like ‘It was a long time ago’ while turning to their spouse to fill in the details.
Confabulation refers to the tendency to produce erroneous material on being questioned about past events. Confabulations may occasionally be grandiose and delusional, but more commonly consist of misordering and fusion of true past memories.
Semantic memory
‘Loss of memory for words and names’ is the principal and hallmark symptom of patients with semantic memory impairment. Naming depends on both knowledge of the target and the linguistic components of name retrieval and articulation. It is important, therefore, to disentangle these aspects. Patients with semantic memory loss are fluent without phonological or syntactic errors in speech. When semantic memory breaks down it produces problems with word production and comprehension although the latter is much less evident to patients and their families. It is usually apparent when processing complex information, for instance, when a number of people are talking or when trying to digest the meaning of written language containing less common words.
It is also important to enquire whether there has been a decline in the patient’s general knowledge: most people have some fund of expert vocabulary related either to their work or hobbies.
Reminder: throughout this book I avoid (wherever possible) the confusing terminology of short-term and long-term memory. In experimental psychology, short-term refers to the very limited capacity store, lasting only seconds as measured by digit span. Alternative names for this short-duration system are immediate or working memory. By contrast, clinicians and the general public usually refer to short-term memory as that assessed by name and address recall after 5 or 10 minutes (see ‘Short-term (working) memory’ in the ‘Memory’ section in Chapter 1 for a fuller discussion). Whenever I use ‘short-term’ it is in the neuropsychological sense.
Suggested areas of enquiry
2. Language
When questioning patients and their relatives about language problems, it is useful to consider language in terms of production and comprehension.
Language production
Language comprehension
Disorders of language comprehension may affect grammar (syntax) or word meaning (semantics). It is difficult to tell these apart as both are often first apparent when trying to follow complex instructions and keeping track of group conversations. Using the telephone is particularly difficult for patients with any degree of comprehension deficit, because all the usual gestural and contextual cues to meaning are absent. Comprehension deficits parallel output disorders in that patients with non-fluent aphasia have difficulty understanding sentences while those with fluent anomic aphasia tend to have problems with word comprehension, although comprehension deficits are nearly always less prominent than output deficits.
Reading
Can the patient still read fluently with comprehension and pleasure? A reduction in leisure reading is a subtle indicator of mild dyslexia, but memory and attentional difficulties may complicate interpretation of this symptom. In dominant hemisphere injury, reading problems usually accompany and mirror spoken language; but in occasional cases, pure alexia may occur. The rare, but well-recognized, combination of alexia with preserved writing ability is a distinct and localizing syndrome, almost invariably associated with right hemianopia, and often with disorders of colour perception and verbal memory problems.
Writing
If a history of writing difficulty is elicited, try to distinguish between breakdowns in spelling or in the motoric control of writing. In the latter, termed ‘apraxic agraphia’ which may occur in basal ganglia disorders, oral spelling is preserved. Remember, most people write very little other than shopping lists and postcards. Agraphia is, therefore, usually underestimated by relatives and patients but is common in neurodegenerative diseases and especially prominent in the corticobasal syndrome.
Note: disorders of reading and writing do not always denote dominant hemisphere pathology. In neglect dyslexia, patients may fail to read one side—usually the left side—of the page or individual words. Likewise, in neglect dysgraphia, one portion of the page or word is omitted. Consider these syndromes if other aspects of spoken language are normal.
3. Numerical skills
Difficulty with manipulating numbers often manifests as inability to use money, and hence to shop alone. Ask also about management of household accounts.
4. Executive abilities
As discussed in Chapter 1, this term refers to the uniquely human ability to initiate, plan, and organize, which in turn involves goal setting and attainment while avoiding distractions and remaining flexible and responsive to changing contingencies. There is, of course, huge variability in baseline abilities in this domain so it is important to assess change from the patient’s normal state.
Two types of questions are helpful. First, general enquiries about the ability to plan, organize, and solve problems plus signs of distractibility or impersistence. The second, and generally more informative, line of enquiry concerns executive function in action. That is to say, the patient’s ability to organize his or her usual life: work, home commitments, use of appliances, DIY, hobbies, and planning holidays and trips.
This is a domain where family members’ views are virtually always more informative. Patients typically lack insight into these problems which are all too evident to family, friends, and colleagues.
5. Visuospatial skills
In contrast to language and memory disorders, which are usually clearly apparent to close observers, deficits in visuospatial ability may be clinically silent. Therefore it is particularly important to make specific enquiries about potential symptomatology.
Dressing ability
Impairment in the ability to dress oneself, so-called dressing apraxia, usually reflects a complex visuospatial deficit rather than a true apraxic (i.e. motor-based) problem. The act of putting on a shirt requires alignment of body parts and mental rotation, which depend upon the non-dominant hemisphere. Thus this type of dressing disorder usually occurs in the context of focal right posterior parietal lesions. Patients with frontal brain damage may show a different disorder of dressing, which consists of a mis-sequencing of garments, and results, for example, in wearing underpants on top of trousers.
Constructional deficits
These are rarely evident without formal testing. Occasionally patients with particular skills or professions (architects, model builders, etc.) may complain of difficulty drawing or in three-dimensional constructions, suggesting right parietal damage. It is always worth asking about hobbies. A specific decline in practical abilities such as DIY or drawing may also suggest right-sided pathology but often reflects impaired executive function.
Spatial orientation
Topographical disorientation, that is to say, getting lost in familiar surroundings, is a common accompaniment of moderately advanced dementia. It may also indicate focal right hemisphere pathology. It may be due to poor spatial memory or failure to recognize landmarks.
6. Neglect phenomena
Neglect of space
Patients with focal right hemisphere lesions often fail to respond to stimuli in the opposite half of extrapersonal space. This may manifest as a failure to talk to visitors on the left side of the bed, a tendency to ignore food on the left half of the plate, constantly bumping into objects and door-jambs on the neglected side, or even failing to read the left half of the page.
Bodily neglect
In its most profound form, patients deny the presence of hemiplegia despite evidence to the contrary. The term ‘anosognosia’ applies to this phenomenon. Less dramatic versions, consisting of a tendency to ignore or under-use one side, are more frequent.
7. Visual perception
Misidentification
Patients with disorders of visual processing may think that faces on the television are actually in the room. Misidentification of familiar faces may also occur, and is common in delirium, when other illusions and hallucinatory experiences are often present (see following ‘Agnosia’ section).
Agnosia
There are a number of fairly rare syndromes involving the inability to identify faces, colours, or objects despite normal basic perceptual processes. In prosopagnosia, patients are unable to recognize faces belonging to friends, acquaintances, or famous people. They can, however, identify these people correctly from voice, dress, or gait. A failure to recognize people by any sensory modality suggests a deficit of semantic memory. In visual object agnosia, subjects fail to recognize objects by sight, but can still identify the same objects by touch. Achromatopsia denotes a loss of colour vision with preserved acuity and object identification. Suggestions for useful screening questions are:
8. Route finding and landmark identification
As discussed in Chapter 3, the ability to navigate in a complex environment depends on a number of cognitive processes, notably the recognition of familiar landmarks as well as learning and retaining spatial maps. Patients with Alzheimer’s disease are prone to topographical disorientation which is particularly prominent in posterior cortical atrophy. This is also common dementia with Lewy bodies.
9. Personality and social conduct
It is difficult to overlook major deficits in memory and language, even with unstructured history taking, and visuospatial disorders should be readily detected by a few simple pen-and-paper tests. Disorders of social cognition and conduct as associated with frontal lobe damage or disease, by contrast, are easily overlooked, and it is in these domains that informant interview is extremely important. One should ask if there have been any changes in character, personality, or social behaviour.
Typical personality changes associated with frontotemporal dementia consist of lack of concern about oneself and others, often with childish, egocentric behaviour, inability to empathize, and lack of inhibition, with a tendency to react impulsively. Patients may become rigid and have difficulty appreciating humour or sarcasm. A lack of spontaneity, with reduced initiation of conversation and activity, is common. Patients have difficulty reading ‘social’ situations and the emotional state of others, leading to faux pas or gaffes. A tendency to bawdiness, such as telling ‘dirty’ jokes or making inappropriate advances, may be reported. Occasionally sexual disinhibition may be extreme. Some patients develop stereotyped patterns of behaviour and may spend hours roaming the neighbourhood picking up abandoned cans or twigs.
With bilateral temporal lobe damage, patients may develop features of the Klüver–Bucy syndrome, consisting of a tendency to eat indiscriminately, sometimes including inedible items (cigarette-ends, soap, etc.), without satiety, altered sexual drive, emotional blunting, and passivity.
10 Eating, appetite, and food preference
Changes in eating behaviours are common in psychiatric illness and one of the cardinal features of frontotemporal dementia. Reduced appetite and weight loss are important biological signs of depression. Increased appetite with a craving for sweet foods, often coupled with stereotyped patterns, such as insisting on exactly the same meal every day for dinner, is typical of behavioural variant frontotemporal dementia. Patients may also suddenly decide to become vegetarian or alternatively switch after many years to eating meat. Many of those with more advanced Alzheimer’s disease suffer reduced appetite but food fads and cravings are unusual.
A decline in table manners is also a feature of frontal type dementias. Any hint of dysphasia should ring alarm bells for the presence of motor neuron disease but it also occurs in basal ganglia disorders, especially progressive supranuclear palsy.
11. Mood
Atypical depressive illness is undoubtedly the commonest treatable disorder in patients presenting to a memory disorder clinic. Complaints of poor memory and especially of an attentional type, which are in excess of those noted by others, should make the clinician consider an affective illness. Besides obvious questions about spirits and mood, the following are useful lines of enquiry:
12. Motivation
You should always enquire about interest level or ‘get-up-and-go’ since apathy is a very common feature in organic brain disease and in depression. Apathy consists of a lack of motivation and diminished goal-directed behaviour with decreased engagement. Although it is a common accompaniment of depression, it is often an independent manifestation of brain disease and has been attributed to anterior cingulate dysfunction. It is typically accompanied by dysexecutive features.
13. Anxiety and agitation
Anxiety is characterized by agitation and unjustified apprehension, feelings of foreboding, and thoughts of impending doom. Patients are irritable, tense, and have poor concentration. Autonomic disturbances (sweating, palpitations, nausea, dry mouth, and lightheadedness) are common. Restlessness, pacing, and fidgeting should also alert you to significant anxiety. Anxiety is a common early feature in all forms of dementia.
14. Delusions and hallucinations
Delusions are false beliefs based on incorrect inferences about external reality that are firmly held despite evidence to the contrary. Delusions in dementia typically focus on theft of property, burglary, and infidelity. In the Capgras delusion, the sufferer claims that people are not who they claim to be, or have been replaced by an imposter. There may be delusions of reduplication (i.e. thinking that there are multiple versions of a spouse or of a place). In the phantom boarder delusion, patients believe that other (often unwelcome) people are living in the house. Any of these delusions may occur in demented patients but appear more commonly in dementia with Lewy bodies. In idiopathic psychotic disorders, such as schizophrenia, delusions are commonly accompanied by evidence of thought disorder. Bizarre and religious delusions are rare in dementia. Grandiose delusions suggest mania.
Hallucinations are sensory perceptions that have the same compelling sense of reality as true sensory experiences but occur without stimulation of the relevant sensory organ. In neurological patients, visual and olfactory hallucinations are commoner than those in the auditory modality. Fairly often there is also at least partial insight. A particular form of visual hallucination, which involves seeing well-formed, and often remarkably realistic, images of animals, faces, and often children, is common in patients with dementia with Lewy bodies and in more advanced Parkinson’s disease, when it is usually secondary to dopaminergic medication. It has been termed peduncular hallucinosis, since it was originally described in association with acute vascular lesions of the cerebral peduncles in the midbrain. Formed visual hallucinations in the absence of cognitive impairment are known as the Charles Bonnet syndrome. Most patients with this disorder have poor eyesight. Vivid hallucinations are common in acute confusional states, when tactile hallucinations of crawling or itching may also occur. Olfactory and gustatory hallucinations are invariably fleeting, and may occur as part of the phenomena of complex partial seizures originating from the medial temporal lobe. Hallucinations may be mood congruent in patients with depressive or manic psychosis.
A sensitive way of enquiring about such phenomena is to ask something like the following: ‘Patients with various kinds of neurological disorder sometimes have unusual experiences when they see, hear, or smell things which may not be there. Have you had anything like that?’.
When talking to relatives, you should ask specifically whether the patient has ever seemed to be seeing or hearing things, or talking to non-existent people.
15. Activities of daily living
Assessment of a person’s abilities to perform the normal duties needed to function in the world is important in deciding whether a patient has ‘dementia’ or simply mild cognitive impairment. It also helps to gauge the level of a person’s overall cognitive impairment.
Activities of daily living (ADLs) are divided into basic (dressing, washing, grooming, and toileting) and instrument (using appliances, handling money, paying bills, dealing with correspondence, using transport, taking medication, etc.). The latter are always affected first and impairment of the former indicates a significant level of cognitive dysfunction.
The Informant Interview
The general format of the informant interview should follow that used with the patient. General open-ended questions should be used first, followed by directed questions to cover each area of cognitive function. Establishing the evolution, pattern, and impact of the deficits is the overall aim.
What were the first observed problems?
In the dementias, this is particularly important because in their end-stages all degenerative diseases tend to produce an indistinguishable picture. The earliest-noted deficit is thus of important diagnostic value. For instance, if there is an insidious decline in anterograde memory, with preservation of personality and social behaviour, then the diagnosis is almost certainly Alzheimer’s disease. Early change in personality and social conduct points to frontotemporal dementia. Word-finding difficulty or speech hesitancy localizes the process to the dominant hemisphere. Spatial disorientation or dressing apraxia as the predominant problem alerts the clinician to the right hemisphere, and so on.
Was the onset acute, insidious, or stuttering?
The mode of onset of cognitive problems is very important. Delirium is always abrupt in onset, and often fluctuating in its course. If an apparent dementing syndrome has an acute or subacute onset over days or weeks, then a depressive pseudodementia should be suspected. The rate of progression is also helpful diagnostically: Alzheimer’s disease progresses insidiously, multi-infarct dementia typically has a step-wise course, dementia with Lewy bodies is associated with fluctuations, and Creutzfeldt–Jakob disease progresses extremely rapidly.
Situation-based problems
Instead of sticking to questions purely about individual cognitive domains it is often illuminating to enquire about particular difficulties in various everyday settings, such as:
Impact on the family and personal relationships
Assessment of the impact of any cognitive change on the family is clearly very important. This also gives the opportunity to enquire about sexual activity. Contrary to the views of the young, sexual intercourse does not stop at 40, or even necessarily at 70. Most spouses dealing with difficult and embarrassing changes in sexual behaviour will value your interest in this sensitive area.
Family History
It is inadequate to record in the medical notes ‘Family history: nil relevant’. This is best exemplified by apparently de novo cases of Huntington’s disease in which a family history is frequently said to be ‘negative’. Detailed probing about the family background invariably reveals important clues, such as an uncle who committed suicide or a grandfather who died at a young age in a mental hospital.
Besides noting the age, state of health, and cause of death of first-degree relatives, preferably in the form of a family tree, you should ask specifically about any family history of neurological or psychiatric illness. As most patients have no idea what constitutes illness in these areas, ask specifically about:
Also enquire whether any family members have ever needed to see a psychiatrist.
Past Medical History
Of particular importance in assessing cognitively impaired patients are the following:
Alcohol Intake
Opinions as to a reasonable level of alcohol intake vary considerably. Although women are said to be more susceptible to alcohol-mediated complications than men, the UK Chief Medical Officer recommended that a ‘safe levels’ for both men and women is no more than 14 units/week. ‘Dangerous’ levels are above these limits. Try to record the average weekly intake in numbers of units per week. One unit is equivalent to half a pint of beer, one small glass of wine, or a measure of spirits. People often underestimate the extent of their alcohol intake, and it is often very useful to go through the last week on a day-to-day basis, adding up everything they recall drinking. An independent assessment of alcohol intake should always be sought from the patient’s spouse or partner.
Tips on Physical Examination
It is not appropriate to describe here the complete neurological examination which should obviously be performed on all patients presenting with cognitive disorders. I shall concentrate instead on a few additional, and perhaps less commonly known, signs which are useful in the detection of focal cerebral abnormalities.
Cranial nerve signs
Smell
I do not test smell routinely. It should, however, be tested in the following circumstances: past history of head injury; dementia, especially of frontal lobe type; complaints of poor taste or smell; and the presence of visual symptoms or signs (suggesting subfrontal pathology).
Vision
As well as testing acuity (in each eye) and pupillary responses and fields, remember to examine for visual extinction or neglect in every patient. Visual extinction is the consistent tendency to ignore stimuli in one half-field (or, rarely, one quadrant) when both sides are simultaneously stimulated by finger wiggling. The visual fields must first be shown to be intact when using single stimuli. Visual extinction is always pathological, and implies damage to the opposite posterior parieto-occipital area. Although included in the category of neglect phenomena, it occurs commonly with right- and left-sided brain damage. This is a good time to test for optic ataxia (visual disorientation) by asking the patient to touch your fingers while wiggling them in each quadrant with the patient fixating ahead. While looking at the eyes also remember to observe for Kayser–Fleisher rings. These brown pigmented rings or crescents are best seen with the patient looking down while illuminated with a torch from the side, and are pathognomonic of Wilson’s disease.
Eye movements
Abnormalities are most often missed because of a hasty examination and a failure to test vertical eye movements. Gaze should be sustained in each of the primary positions (i.e. horizontal right and left, vertical up and down). As well as following (pursuit) movements, testing should include rapid voluntary sideto-side and vertical (saccadic) movements. These may be selectively disrupted in basal ganglia disorders (for example, Huntington’s disease). A severe and selective deficit in vertical eye movements occurs in progressive supranuclear palsy (Steele–Richardson–Olszewski syndrome) (see ‘Progressive supranuclear palsy’ in the ‘Dementia’ section in Chapter 2), and also following upper brainstem and thalamic strokes.
Frontal release signs
A large number of primitive frontal signs have been described. These reflexes are released from normal inhibition in the presence of frontal lobe damage or disease. Their interpretation is difficult, because some occur in a high proportion of the normal elderly, and they rapidly fatigue on testing. In descending order of usefulness they consist of the following:
Motor system
Postural arm drift
This is tested by asking the patient to maintain a static position of the outstretched arms in the horizontal position with the eyes closed. Downwards and usually inwards drift of the arm is a frequent sign of contralateral hemisphere disease, and may be found in the absence of any other motor signs. Observation of the hands and fingers in this position is also very useful for detecting involuntary choreiform or dystonic movements.
Involuntary movements
These are best observed when taking the history. Chorea is often overlooked, and attributed to fidgetiness. If there is any doubt about their presence, ask the patient to lie still on the bed with the eyes gently closed. Also watch when the patient is walking; this often exacerbates chorea, producing characteristic finger-flicking movements, and may also bring out dystonic limb-posturing.
Sensory system
Astereognosis
This is a form of tactile agnosia in which the patient is unable to recognize objects despite normal sensation, coordination, and motor function. Deficits are associated with contralateral parietal lesions. It occurs equally with right- and left-sided damage.
Graphaesthesia
The inability to recognize letters or numbers traced on finger tips is also associated with damage to the somatosensory parietal cortex. A few practice numbers should be drawn for the patient with the eyes open, making sure that the numbers traced out are oriented towards the patient.
Sensory inattention
This denotes a failure to appreciate a stimulus when a similar stimulus is applied simultaneously on the opposite side. For instance, patients can register when their right hands are touched, but when both sides are simultaneously touched they report only the left-sided stimulation. This method is often called double simultaneous stimulation. It occurs frequently with right and left parietal lesions.
Gait and balance
No neurological examination is complete without watching the patient rise from a seated position and walk 20 paces or so. Impairment in the initial stages, with the ‘glued to the floor’ sign, is characteristic of gait apraxia associated with normal-pressure hydrocephalus. Small, rapid festination, with a hunched posture and lack of arm swing, characterizes Parkinson’s disease. Particular difficulty with turning or changing direction is a common accompaniment of Parkinson’s disease and other degenerative extrapyramidal disorders (such as progressive supranuclear palsy). The choreiform movements of Huntington’s disease are frequently exacerbated by walking. Visual neglect may be apparent if the patient consistently bumps into objects to one side. When sitting, patients with progressive supranuclear palsy tend to collapse backwards en bloc rather than adjusting their back and leg positions as normal.
The ‘stork’ manoeuvre
If the patient can balance on one leg with arms folded across his or her chest and with eyes open, then any significant disorder of balance and practically any lower limb pyramidal weakness can be excluded.