RECOGNISING AND EVALUATING DISORDERED MENTAL STATES: AGUIDEFORNEUROLOGISTS

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1 Correspondene to: Dr John Moriarty, Department of Psyhologial Mediine, Kings College Hospital, Denmark Hill, London SE5 9RS, UK; slam.nhs.uk RECOGNISING AND EVALUATING DISORDERED MENTAL STATES: AGUIDEFORNEUROLOGISTS THE T JMoriarty J Neurol Neurosurg Psyhiatry 2005; 76(Suppl I):i39 i44. doi: /jnnp he overlap between neurology and psyhiatry should be obvious, given the two disiplines shared onerns with disorders of the human nervous system and the effet of these disorders on suh fundamental aspets of our speies as thoughts, beliefs, pereptions, and feelings. Nevertheless there is quite a division in terms of training, speialists (medial or otherwise), and servie strutures for patients who have disorders of the brain or mind. These strutural and professional divisions an arguably lead to diffiulties for patients aessing appropriate assessments and treatments. In the UK at least it is not urrently a requirement of either neurologial or psyhiatri training to have experiene of the other speiality, although progress is being made slowly in this respet with the introdution of more formal neuropsyhiatry training modules into both neurology and psyhiatry higher training shemes. This issue of Neurology in Pratie may go some way towards addressing this gap. Perusal of the literature will reveal that there have long been those arguing for bridges, rapprohements, and integration between the two disiplines, but real hange is harder to see. There ontinues to be ontroversy within psyhiatry whether the disipline is mindless or brainless and in whih diretion it and its pratitioners should move. The persistene of mind brain dualism is sadly all too ommon in our medial pratie. It is not unommon for patients with primary psyhiatri illness to have minimal examination of physial state and the mental state examination is rarely done in a systemati way in general medial or even neurologial settings. Of ourse, sometimes that is entirely appropriate, but just as psyhiatrists should hopefully be able to detet and desribe physial signs, so too should the neurologist be able to desribe adequately and systematially abnormalities of mental state. Studies have repeatedly shown that psyhiatri illness in medial patients very often remains unreognised. While this may have important impliations for the treatment of patients, there is evidene that detetion may be inreased both by inreasing the length of time available for assessments and by improving the assessment skills themselves. Communiation styles whih failitate the detetion of psyhiatri morbidity or o-morbidity inlude listening, open ended questioning, developing an empathi rapport, interviewing patients in private, and using verbal and non-verbal behaviours to enourage dislosure (not, for example, asking questions while writing notes or interviewing people in bed surrounded by trainees or students). MENTAL STATE It is usual when desribing mental states to divide the examination into the following headings: appearane and behaviour, orientation, attention and onentration, memory, mood, speeh and language, pereptions and thoughts and insight (box 1). This artile aims to review the basi omponents of the mental state examination and give a struture for reording it. Problems of terminology or diagnosis that are likely to onfront neurologists are disussed. Appearane and behaviour Initial examination of the patient will allow the examiner to omment on various aspets of appearane and behaviour. This inludes the general level of motor ativity, apparent distratibility, self are, appropriateness of dress (any evidene of disinhibition?), ooperativeness, and hostility. The manner of initial ontat may be observed: eye ontat, hand shaking, and posture. Of ourse, like many signs on examination, these have limited diagnosti signifiane in isolation but need to be part of an integrated mental state examination. Understandably, in busy wards with junior staff hanging shifts, detailed behavioural observations may be diffiult. When this is the ase it may be helpful to use observational harts for example, sleep harts, ativity reords, dietary reords. These are simple diary style reords usually divided into manageable slots, hourly or less frequently to reord patient behaviours. A partiularly ommon linial senario deserves speial mention. Delirium synonyms for whih inlude aute onfusional state, aute organi brain syndrome, aute organi reation, and i39 J Neurol Neurosurg Psyhiatry: first published as /jnnp on 16 February Downloaded from on 30 Marh 2019 by guest. Proteted by opyright.

2 i40 Box 1: Components of the mental state Appearane and behaviour Orientation Attention and onentration Memory Mood and affet Speeh and language Pereptions Thought ontent Insight aute psyho-organi syndrome ommonly auses a flutuating linial piture whih an lead to different observations and opinions in different members of the linial team. These inonsistenies may even be mistakenly attributed to feigning or funtional overlay. The ative delirious patient, who is restless, agitated, and hyperresponsive to stimuli, is rarely missed as he auses onsiderable management problems. The hypoative delirious patient, though more ommon, is more likely to be missed as he is undemanding, sleepy, and quiet. Restlessness may be a feature of anxiety or delirium. A rather speifi and extremely distressing form of restlessness is akathisia where the patient has a strong subjetive urge to pae and annot sit still. Most often assoiated with neurolepti mediation, it is also seen with some antidepressants. It may be relieved to some extent by benzodiazepines but treatment is to remove the ause. In addition to the patient s behaviour, it may be useful to observe his interation with his immediate environment. Is there evidene of regression (soft toys), obsessionality (overly neat bedside tables), dependeny (attentive relatives), or abnormal preoupation with illness (textbooks)? Orientation It is surprising how disorientation in patients may be missed. The apparently alert patient may know he is in hospital, know the time (a quik glane at a lok), but reveal onfidently the year as being a deade or so past. The aronym OTPP usually suffies as an examination of the ability of the human to desribe his unique individual nature and to loate himself in spae and time. In reality disorientation in person that is, not knowing who you are is rare exept in advaned organi brain disease. It may be diffiult or impossible to establish in severe aphasia. In the absene of these or obvious delirium disorientation in a person is highly suggestive of a dissoiative state, espeially psyhogeni fugue or dissoiative amnesia. In evaluating disorientation, it is useful to go beyond merely soring the patient as orientated or not. Minor degrees of disorientation in time are ommon in hospital settings and it may be more fruitful to listen to how the patient tries to orientate himself. Attention Disorientation most ommonly suggests problems with attention and indiates a possible delirium. Traditionally attention is examined using serial 7s or bakwards spelling. Digit span may be more useful as it relies less on numerial or spelling ability. Poor attention may beome obvious during the general interview as the patient drifts off from topi to topi or is unable to reount something that has been explained to him. It may be prudent to try and establish this relatively early on as it may make muh of the history taking futile. Memory The examination of memory an be relatively simple and superfiial or the subjet of detailed and sophistiated neuropsyhology. As in all neuropsyhiatry, the informant history may be muh more revealing than the patient interview alone, as the patient may be more or less unaware of his diffiulties. General questions about reent personal or publi events are useful as are more speifi probes about memory of routes, duties, onversations, soap opera plots, et. Elementary formal examination of memory using the familiar three objets or name and address may be inluded as part of a routine or more extended ognitive assessment. Strutured ognitive examination Whether one deides to use a standard assessment suh as the mini mental state examination, frontal assessment battery, or Addenbrooke s ognitive examination, abnormalities should be explored more fully and tailored to the individual patient. A patient who sores 29/30 on a mini mental state examination, losing one point for opying interseting pentagons, for example, ould be asked to draw a lok fae to explore whether there is a real finding or whether this was just a one-off error. Certain findings on standard bedside ognitive testing may suggest a psyhiatri disorder. Problems with onentration are ommon in depression and anxiety. Poor performane in a range of tests with a pattern of giving up early or despairing with I don t know or I an t do that answers may suggest the pseudodementia of depression, although it must be remembered that the ognitive impairment of depression is a real impairment and not simply seondary to loss of drive, interest, or motivation. Furthermore, depression may itself be a risk fator for the development of dementia and psyhiatri symptoms are an indiator of severity in mild ognitive impairment. Approximate answers, originally desribed as part of the Ganser syndrome, whih are patently absurd answers, suggest a dissoiative state. Examples would inlude What is two plus two? Five or What olour is grass? Blue The examiner should be vigilant for lues to an abnormal mental state whih may lie in the ontent of a patient s answers to parts of the examination suh as Write a sentene or Desribe what you see in this piture. Thus a patient who is hypomani may desribe things in glowingly enthusiasti language. The paranoid patient may reveal fears or preoupations and the depressed patient may spontaneously reveal feelings of guilt, hopelessness, inadequay, or despair. Mood and affet The most important abnormalities of mood are depression, anxiety, and elation. The eliiting of depressed mood or anxious mood is partiularly important as these are eminently treatable, ommon o-morbid disorders in neurologial pratie. The most basi tool in eliiting mood symptoms is time. Unfortunately this is not always readily available but it is at least arguable that time spent listening to patients might reveal problems earlier on and prevent unneessary or ostly investigation. The symptoms should be asked for in an open ended way, leaving silenes if neessary: How are you feeling? How are your spirits? How J Neurol Neurosurg Psyhiatry: first published as /jnnp on 16 February Downloaded from on 30 Marh 2019 by guest. Proteted by opyright.

3 has all this affeted you? may be muh more revealing questions than Have you been depressed?. In addition to subjetive unhappiness, patients with low mood desribe loss of enjoyment (anhedonia), or deadening of emotions. If there is a sense that the patient has indeed been experiening low mood, the examiner should go on to ask about speifi biologial features (also alled melanholi features) suh as sleep disturbane (espeially early morning wakening), diurnal variation (worse in morning), appetite disturbane, weight loss, and loss of libido. Important ognitions whih may suggest depression are feelings of guilt and hopelessness. Anxiety and irritability are also features of mood disturbane and should be asked about speifially. Elated mood is suggested by talkativeness, irritability, pressured speeh, and grandiose ideas. Muh less ommon than depression, it has been thought to be more assoiated with right hemisphere damage involving ortial or subortial limbi areas. Sustained heerfulness has traditionally been assoiated with demyelinating disease and may reflet frontal involvement revealed on neuropsyhologial examination. Elated mood neessitates a areful review of mediation. Steroids, antidepressants, or stimulant drugs are probably most ommonly impliated. Anxiety is arguably the most ommon mood problem seen and the linial assessment may entre on whether to onsider it as a primary mood disorder (perhaps on a spetrum with depression) or a more speifi anxiety disorder (see below). The term affet is used with a number of omplementary meanings. Sometimes it is reserved for the desription of the prevailing mood state at a partiular point in time, while the term mood is used for the overall state over a longer period of hours or days. Others use the term affet to desribe a more objetive desription of mood, perhaps related to the effet the patient s mood appears to have on the examiner, in ontrast to the more subjetive mood state of the patient. The most useful sense of the word is probably when it is used to desribe less the emotional tone or flavour (depressed, anxious, irritable, elated) but rather the range, variability, and appropriateness of the emotional reation within the interview. Thus one may speak of onstrited, blunted, flattened, inongruous, or inappropriate affet. Sudden hanges in mood, often short lived and from whih the patient an be easily distrated, are suggestive of lability of affet, often seen in assoiation with ortial or subortial disease, and should not be onfused with the persistently lowered mood of depression. Pathologial laughter is rare. It may be assoiated with a subjetive sensation of mirth or be onfined to the motor at of laughter. The neuroanatomi orrelates of these funtions remain unlear but may again involve limbi strutures. Gelasti seizures are usually not assoiated with a subjetive sense of mirth and the laughter may have a ourse, stereotyped, fored quality. Assessment of suiidal feelings and risk The assessment of patients who have feelings of hopelessness and ideas of suiide an be a partiular diffiulty. Patients are aware that their ideas of harming themselves may be seen as evidene of mental illness and so may be relutant to divulge them. Cliniians may find the risk of self harm diffiult to manage in a risk averse ulture. The general priniple of an open listening style in a private safe environment is of ourse important. A guide to some of the questions whih may be Box 2: Questions to eliit suiidal thoughts How low do you get? How do you feel about the future? Do you ever feel like giving up? Do you sometimes wish you weren t here? Have you been thinking of suiide? Have you thought how you would hurt yourself? What might stop you? useful and some of the pointers towards a higher risk are listed in boxes 2 and 3. One of the dilemmas faing the liniian who has eliited signs of low mood is what to do next. This is dealt with elsewhere in this issue, but an important aspet of the evaluation of the signifiane of low mood is a judgement as to whether the mood is persistently and pathologially low or whether the low and anxious mood is part of the normal reation to the distress and unertainty linked to faing a possible neurologial diagnosis. Clues that it may be the former are its persistene and the presene of melanholi symptoms or feelings of guilt and hopelessness as desribed. Often, the most appropriate ourse of ation is to allow the patient to artiulate his fears or feelings and then adopt a wait and see approah. If doubt persists, an empirial trial of antidepressant treatment may be needed. Patient groups in whom affetive disturbane may be partiularly diffiult to diagnose inlude those with learning diffiulties and autisti spetrum disorders. The latter may have a very different subjetive experiene of mood disorder and may not have the usual language to desribe their experienes. Affetive disorders may have to be inferred from altered behaviours for example, loss of interest in usual routines, sleep or appetite disturbane, or aggression. Again, an empirial trial of treatment may be neessary. Anxiety Anxiety is haraterised by a subjetive sense of disomfort and fear. This may be entirely appropriate and related to the possible diagnosis, treatment, or prognosis of a neurologial ondition. It may also be speifi and reveal fear of illness as part of hypohondriasis or even speifi phobias. It may also be part of a generalised anxiety or depressive illness (table 1). Speeh In non-neurologial settings it is usual to examine speeh by ommenting partiularly on the rate and rhythm of speeh. The overtalkative patient may be anxious or hypomani, while slowness or monotony of speeh suggests depression. The speeh patterns of patients with shizophrenia may be Box 3: Risk fators for suiide Previous attempts Major mental illness Substane use Reent loss or threat of loss Soial isolation Rootlessness Ative suiidal thoughts Command halluination Perseutory beliefs Agitation, distress i41 J Neurol Neurosurg Psyhiatry: first published as /jnnp on 16 February Downloaded from on 30 Marh 2019 by guest. Proteted by opyright.

4 i42 Table 1 Diagnosis Phobi Pani Generalised Adjustment or PTSD Somatoform Simple lassifiation of anxiety states Worries PTSD, post-traumati stress disorder. Afraid of speifi situations, stimuli leading to avoidane of these Reurrent attaks of severe anxiety in an unpreditable way Relatively free-floating anxiety not onfined to speifi situations or disrete attaks Shorter or longer term reations to a speifi stressor. PTSD haraterised by harateristi reliving experienes with avoidane and mood and onentration problems Inludes persistent physial symptoms (somatisation) and persistent worry about illness (hypohondriasis). highly unusual, with mannerisms and stereotypies, or relatively normal but with unusual ontent. In the neurologial setting speeh abnormalities may reflet an organi neurologial disorder. The speeh of the patient with Parkinson s disease may mimi the slowing and loss of intonation seen in depression; the patient with frontal impairments (whether ortial or seondary to subortial disease) may show slowing and loss of rihness or disinhibition with volubility. Cirumstantiality and overinlusiveness are seen in obsessive patients, but apart from being frustrating for the liniian pressed for time, they are of doubtful linial usefulness. Regressed, hild-like speeh may be a feature of dissoiative disorders. Slurred, dysarthri speeh should always raise the possibility of organi illness, espeially drug toxiity. In psyhiatri pratie the most frequently seen speeh abnormality is probably that refleting the thought disorder of shizophrenia. This may mimi the disorganised and illogial speeh patterns of the aphasi patient, but the differentiation will usually be obvious from the history. Global aphasi patients may indeed develop what is in effet a disorder of thought, beause of the profound effet of disordered language on thinking itself. Apart from the history, it may be possible to distinguish the aphasi from the shizophreni speeh disorder by the former s shorter responses and attempts to enlist the examiner s aid, and the latter s more bizarre themes. Pereptions It is probably fair to say that abnormal pereptions, partiularly halluinations, are one of the hallmarks of psyhiatri illness. Hearing voies is suh a harateristi and distressing symptom of shizophrenia that there are selfhelp and therapeuti groups primarily to help people ope with these symptoms. Halluinatory behaviour, whih may appear as muttering or mumbling to oneself, may be one of the most stigmatising symptoms around, leading to a person being seen as razy with the attendant stigma of dangerousness, unpreditability, or unreliability. Patients are themselves autely aware of this and so may be relutant to answer diret questions about halluinations. Perhaps as ommon, however, is that liniians are relutant to ask about suh symptoms, for fear of annoying the patient. It is usual therefore to introdue questions about halluinations one a degree of rapport has been established and any suspiiousness or hostility on the part of the patient has been hopefully redued. As with any line of questioning it is advisable to begin with relatively open questions ( Any unusual experienes?, Anything distrating you? ) before moving to more losed questions. The experiene may need to be normalised to some degree: People sometimes tell me they hear others talking to them or about them. Has that ever happened to you? Auditory halluinations should be larified as to nature (some ommentaries an be banal or reassuring) and in partiular whether there are ommand halluinations. The latter are assoiated with ating on the ontent of the halluination and may therefore be assoiated with a higher degree of risk of violene to the self or others. Visual halluinations are more suggestive of organi disease. Transitory halluinations halluinations whih are poorly formed, variable in ontent, and not assoiated with omplex fixed delusions are harateristi of organi brain syndromes suh as delirium. Visual halluinations in partiular are seen ompliating Parkinsons disease and its treatment and, ompared to patients with primary psyhiatri disturbane, insight into the abnormal nature of the experienes may be relatively well preserved. Strongly mood ongruent halluinations (rotting smells, ausatory voies, visions of hell, in depression) should raise the suggestion of affetive disturbane. Visual halluinations are seen in patients with visual loss following peripheral damage (Charles Bonnet syndrome), oipital epilepsies, and oipital stroke. Content of thought Under this heading it is usual to onsider firstly a desription of the patient s main preoupations. Seondly, it is usual to look for speifi pathologial thought ontent suh as delusions, overvalued ideas, or obsessions. Finally, it may be useful to explore the patient s belief systems espeially regarding disease ausation, investigation, and prognosis. Speifi disorders of thought suh as disordered experiene of the possession of thoughts are harateristi of shizophrenia. Delusions Rather like halluinations, delusions may be fragmentary (they are out to kill me/we are sinking) or systematised (an elaborate narrative with haraters, arguments, plot, and preditions). The former suggest an aute organi brain syndrome whereas the latter are harateristi of more hroni psyhoti disorders suh as shizophrenia and dementia. The harateristi feature of the delusion is the fixity with whih the belief is held. Evidene is reruited to support the belief, never to hallenge it. Patients with long standing delusional beliefs in shizophrenia may have aommodated to their beliefs and may funtion relatively well in our ommunity despite them. For example, a patient who believes his brain is being stored in the USA for experiments by a well known rok musiian ontinues to look after himself and ollet his benefits while knowing he is the subjet of government and media surveillane. Sometimes very depressed patients may paradoxially report that their mood is fine but that they know they will shortly be killed, or that the dotors are planning their disposal. Obsessions and repetitive behaviours It is relatively ommon to find stereotyped and repetitive behaviours in patients with neuropsyhiatri disease. There an be onfusion as to the meaning of these, and in partiular how they relate to obsessive ompulsive disorder (OCD). Patients with a range of disorders affeting global ognitive J Neurol Neurosurg Psyhiatry: first published as /jnnp on 16 February Downloaded from on 30 Marh 2019 by guest. Proteted by opyright.

5 funtion, suh as dementia or learning disability, may show a restrited pattern of behaviours and an intolerane to the interruption of these behaviours. This is partiularly a feature of dementing syndromes affeting the frontal lobes, and indiates orbitobasal involvement. Repetitive stereotyped behaviours are a predominant and defining harateristi of autism spetrum disorders (a term used to enompass autism and the more nosologially ontroversial syndromes of high funtioning autism and Asperger s syndrome). Repetitive behaviours are also a feature of disorders of the basal ganglia and are seen in Wilson s disease, Huntington s disease, and neuroaanthoytosis. They are also a ore feature of Gilles de la Tourette s syndrome (GTS). These behaviours seem to lie on a ontinuum with OCD. Thus, while the diagnoses listed (with the exeption of the developmental disorders) may primarily ome to the attention of neurologists, patients with OCD will usually be referred to psyhiatrists or psyhologists. The prinipal differene is that patients with primary OCD will have a strong subjetive sense of the strangeness or illogiality of their thoughts or fears and will often atively resist them. There is pronouned assoiated anxiety and ompulsions develop to redue this anxiety. Interrupting this yle of avoidane and ompulsive behaviours by enouraging a graded sensitisation to the assoiated anxiety is the priniple on whih the behavioural therapy of OCD is based. Patients with organi syndromes are less likely to be aware of the behavioural problems. Though they may develop anxiety in reation to any attempt to interrupt them, they are less likely to be motivated themselves to bring about hange through exposure to anxiety and treatment strategies are more likely to be based on reinforement of positive behaviours. Patients with GTS seem to lie between these two poles and this may relate to whether there is any assoiated global ognitive diffiulty. Other areas of assessment Illness beliefs In addition to the standard assessment of mental state, whih fouses on the detetion of abnormalities of mental state and is really the psyhiatri equivalent of the physial examination, it is often time well spent if the liniian an eluidate some of the patients beliefs (whih may be wrong but not delusional!) regarding neurologial illness and its treatment. This is partiularly important in the area of somatisation, onversion and dissoiation, and somatoform disorders generally. Clearly this group of patients is one whih neurologists find partiularly diffiult to treat and it is almost harateristi that patients will develop a poor relationship with some liniians who will ome to dread the next visit of that partiular patient. It is probable that muh of this annot be avoided but there are some general strategies whih may help. It is important, in my view at least, not to assume that physial symptoms whih annot be explained organially must have a psyhiatri explanation. While undoubtedly some patients may have a masked depression or anxiety state, others will not. This group of patients is more likely to have problems on the somatisation/ somatoform disorder spetrum and may not do well by being told that they have a psyhiatri disorder. From experiene, it seems that suh patients need extra effort to ensure they feel their onerns have been taken seriously and understood. They may then need reassurane (not that there is nothing wrong but that this is not an unusual pattern and that a good degree of reovery an be hoped for). They may also need skilled and diplomati management to avoid unneessary or harmful investigations or treatment. Speifi questions may help eluidate the problems with these patients. For example, asking them what they think may be wrong, or asking about illness beliefs. Do they think headahe usually indiates serious illness? How ommon is tiredness? Finally reassurane should be given arefully as it is all too often heard as there is nothing wrong. Aute hange in mental state A ommon experiene in the aident and emergeny department is the patient presenting with an aute hange in mental state, and it has even been known for unseemly disputes to arise between psyhiatrist and neurologist as to whih disipline should take on the assessment of the patient. The psyhiatrist will want their neurology olleagues to exlude an organi ause and the neurologist may wish the psyhiatrist to diagnose funtional illness. What might be the pointers towards a patient needing thorough organi work up? Very sudden hanges in mental state may suggest an underlying organi problem. Intoxiation with street or presribed drugs should always be onsidered and toxiology should be a routine part of the assessment of patients with unusual or suddenly hanged mental states. Foal neurologial signs are not a feature of ommon psyhiatri disorders like depression or shizophrenia. Age may also be a pointer: signifiant mental state hanges in the elderly or in hildren should probably be assumed to have a possible organi aetiology. Aute psyhosis suggesting shizophrenia may present at any age, but typially first presents between the ages of 15 and 35 years. Affetive disorders present more ommonly in middle age and later life. Alohol It is estimated that between 10 20% of patients on general medial wards may have signifiant alohol problems. Alohol problems may be suggested by the diagnosis; in the neurologial setting organi brain syndromes inluding amnesti syndromes and dementias may be most ommon. Establishing a history of harmful alohol use or dependene may be diffiult sine denial is one of the features of dependene and beause patients will antiipate rejetion or withholding of treatment beause of what might be seen as judgmental attitudes on the part of staff. The detetion of alohol problems is important for a number of reasons. Substane using patients are at relatively high risk of psyhiatri illness and of ompleted suiide. Heavily dependent patients may develop life threatening delirium tremens in the ontext of an aute hospital admission if the alohol history is missed. Finally, there is some evidene that advie given about harmful alohol use an be benefiial if given in medial settings. There are various sreening instruments available for example, the FAST, AUDIT, or CAGE questionnaires. Consiousness It is perhaps worthwhile straying off into this most vexed of terms as it an lead to onfusion between neurologists and psyhiatrists. It is traditional in psyhiatry to use the term onsiousness to refer to the integration of our awareness of, monitoring of, and response to the environment. The term is problemati, however, beause of its multiple meanings. One author defines a disturbed state of onsiousness as follows: a state in a person in whih he has no i43 J Neurol Neurosurg Psyhiatry: first published as /jnnp on 16 February Downloaded from on 30 Marh 2019 by guest. Proteted by opyright.

6 i44 experienes at all, or in whih all of his experienes are deviant, onerning other or more qualities than tempo and mood olouring, from those he would have under similar stimulus onditions in his habitual waking state. The state is a disturbed state of onsiousness only if the individual annot return to, and remain in, his habitual state by deiding to do so himself, and if others bring about a lasting return to his habitual state by the appliation of a simple soial proedure. Zeman simplifies things and identifies three prinipal meanings. The first is onsiousness as the waking state. This is the most ommon meaning in neurologial pratie. It is distinguished from unonsiousness. The unonsious patient is perhaps asleep or in a oma. The differene is quantitative. The degree of onsiousness an be measured using instruments like the Glasgow oma sale. Consiousness has another meaning whih is dealt with by philosophy and relates to the subjetive elements of experiene and relates to terms like self awareness. This is generally held to be a partiular feature of human beings (unlike the first meaning) and debate ontinues as to whether it ould be a feature of artifiial intelligenes or non-human animals. Psyhiatry uses the terms onsious and unonsious with a further, though of ourse related meaning, whih is partiularly important in how we oneptualise the problems of patients with symptoms that do not have a neurologial explanation. Thus we speak of the unonsious or at least unonsious motivations. Whether these onepts make sense philosophially is one thing (and thankfully this is, to use the lihé, beyond the sope of the present artile ), but it is ertainly a ommon part of our urrent onepts of these syndromes that the internal or external reinforers of behaviours and symptoms are not usually known to the patient and therefore not under voluntary ontrol. REFERENCES 1 Lishman WA. Organi psyhiatry. The psyhologial onsequenes of erebral disorder. Oxford: Blakwell Siene, The lassi single author textbook of neuropsyhiatry and an invaluable referene. 2 World Health Organization. Poket guide to the ICD-10 lassifiation of mental and behavioural disorders. Edinburgh: Churhill Livingstone, Hardly exiting reading but the soure of the diagnosti riteria used for the diagnosis of mental disorder. 3 Hamilton M, ed. Fish s linial psyhopathology. Bristol: Wright, Muh more readable and lear than other similar texts. 4 Hodges JR. Cognitive assessment for liniians. Oxford: Oxford University Press, A readable and linially pratial guide to the examination of ognition. 5 Hodes M, Moorey S, eds. Psyhologial treatment in disease and illness. London: Gaskell and The Soiety for Psyhosomati Researh, Gives a useful introdution to some of the psyhologial models and approahes used to help patients with physial symptoms. 6 Liddle P. Disordered mind and brain: the neural basis of mental symptoms. London: Gaskell, An elegant single author aount of the advanes in understanding psyhopathology whih have arisen partiularly from the tehniques of funtional neuroimaging. 7 Slater E. Diagnosis of hysteria. BMJ 1965;i: Walshe F. Diagnosis of hysteria. BMJ 1965;ii: The arguments in these two lassi papers for and against the onept of hysteria have not been fully resolved 40 years on. 9 Zeman A. Consiousness. Brain 2001;124: A useful introdution to some of the language from a neurologial rather than a philosophial perspetive. J Neurol Neurosurg Psyhiatry: first published as /jnnp on 16 February Downloaded from on 30 Marh 2019 by guest. Proteted by opyright.