4 Classification and assessment in psychiatry4.1 Descriptive psychopathology
4.1.3 Disorders of cognition
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Written by Resident Doctor Committee · Published
Consciousness and alertness
Assess alertness and attention before interpreting memory or other cognitive scores, because drowsiness, poor hearing, language difficulty and inattention all lower apparent recall.
State | What it is |
|---|---|
Clouding of consciousness | Mere drowsiness |
Somnolence | Pathological drowsiness (for example from morphine) from which the person rouses to normal, clear awareness |
Twilight state | Narrowed consciousness, classically epileptic and often after a seizure, with relatively well-ordered, purposeful behaviour, sometimes hallucinations, and later amnesia |
Oneiroid state | Absorption in hallucinatory experience |
Vegetative state | Wakefulness without awareness: sleep-wake cycling with spontaneous eye opening and closing survives, unlike coma |
Sundowning | Confusion and behaviour worsen later in the day |
A twilight state is told apart by its ordered behaviour: delirium is disorganised, and a fugue is psychogenic.
Attention
Attention is the earliest and most sensitive cognitive domain to fail in delirium.
Distractibility is attention captured by trivial or irrelevant external stimuli, and it is common in mania and delirium.
Selective inattention (Harry Stack Sullivan) is attention failing only for anxiety-provoking material while it works normally for everything else.
Serial sevens, months of the year backwards and spelling a word backwards reverse an overlearned sequence, so they test attention and concentration.
Months of the year backwards, the attention item of the 4AT, suits repeated ward checks better than serial sevens, which numeracy, education and anxiety confound.
Performance on every attention task depends on education, language and familiarity with the task.
Delirium and dementia
Delirium differs from dementia by clouded, fluctuating consciousness and attention, whereas consciousness stays clear in most dementias until late.
Acute change and fluctuation suggest delirium, but fluctuation also occurs in some dementias.
Simple attention is usually spared in mild to moderate dementia, so clearly failed attention on a bedside test should prompt a search for delirium on top of dementia.
Intact performance on a structured attention task is the finding that most argues against current delirium, because delirium is defined by disturbed attention and awareness.
Delirium, depression and neurodegeneration can coexist, so treat reversible contributors and reassess.
Orientation
In delirium orientation to time is the most fragile domain and fails first, then place, then other people, with the person's own identity kept longest.
Orientation to person is tested by asking the patient to identify people present, and it is usually the domain lost last in a confusional state.
Intact orientation does not exclude a memory disorder, nor does it exclude delirium.
Age disorientation in chronic schizophrenia is a stated age at least five years from the true age, usually an underestimate.
Digit span
Digit span is a bedside test of attention that needs only the examiner's voice.
Condition | Task | What it tests |
|---|---|---|
Forward | Repeat the digits in the order given | Attention and immediate verbal recall (short-term memory, which psychiatry calls immediate memory), not executive function |
Backward | Repeat the digits in reverse | Working memory, because the string must be held and manipulated |
Sequencing (WAIS-IV) | Say every digit back in ascending numerical order, repeats included | Working memory |
Normal forward span is seven plus or minus two in Miller's account of short-term memory capacity; a forward span of about six, give or take one, is also given as normal.
Backward span normally runs one to two digits below forward span, so that gap alone is not a working memory deficit.
A normal forward span with a markedly reduced backward span indicates a verbal working memory deficit, since forward repetition needs only attention and brief storage.
Backward span falls early in delirium.
Standard administration gives two trials at each span length and stops a condition only when both trials at one length are failed.
In the Wechsler Adult Intelligence Scale, fourth edition (WAIS-IV), digit span is the core Working Memory Index subtest, measuring immediate auditory attention and working memory most purely; arithmetic also loads on calculation.
Memory: stages and testing
Registration is the first stage of memory: taking material in and repeating it at once.
Retention is the storage that follows, tested by recall after a delay.
Term | What is tested |
|---|---|
Immediate recall (registration) | A small amount of material, recalled at once with no delay |
Delayed recall | Recall after minutes |
Recent memory | Recall after hours or days |
Remote memory | Recall after years |
Delayed free recall is retrieval of studied items without cues, in any order, after an interval filled by another task.
Recognition is accurate identification of a target once it is shown, with a feeling of familiarity, after unprompted retrieval has failed.
Recollection is actively reconstructing past events without a cue.
Verbal memory is tested by recall of newly presented spoken material, as in the verbal paired associates task (cued recall of heard word pairs).
Finding | Suggests |
|---|---|
Poor initial registration | Attention, comprehension, sensory or encoding problems |
Poor delayed recall with little benefit from cues or recognition | Storage or consolidation difficulty |
Poor free recall improved by cues or recognition | Retrieval difficulty |
Memory systems
System | Content | Test |
|---|---|---|
Immediate span | Briefly held information | Forward digit span |
Working memory | Holding and manipulating information | Backward span or sequencing |
Episodic | Recent and remote personal events | Delayed recall and recognition; corroborated life history |
Semantic | Facts and meanings | Naming and knowledge tasks |
Implicit (procedural) | Skills and habits | Performance across practice |
Prospective | Remembering future actions | History of daily function |
Implicit (non-declarative) memory shows in performance without conscious recollection and covers skills, habits, priming, conditioning and non-associative learning; it is spared in amnesia.
Healthy ageing brings slower processing and psychomotor speed and some loss of working memory and problem solving.
Accuracy, crystallised knowledge, remote personal memory and procedural memory are preserved in ageing, unlike declarative, executive and speed-dependent functions.
Amnesia
Anterograde amnesia affects new learning; retrograde amnesia affects memories from before the onset.
Post-traumatic (anterograde) amnesia after head injury is the gap from the injury until continuous memory returns, with events before the injury intact.
Ribot's law is the temporal gradient of retrograde amnesia: recent memories are lost first and the oldest are best preserved.
Alcoholic blackouts are discrete periods of anterograde amnesia during intoxication, with immediate and remote memory preserved.
Korsakoff syndrome has anterograde amnesia, an episodic memory failure, as its core deficit, while working, procedural, implicit and semantic memory are preserved.
Feature | Organic amnesia | Dissociative amnesia |
|---|---|---|
Episodic loss with spared semantic and procedural memory | Present | Present |
Loss of personal identity | Absent | Present |
Confabulation | Can occur | Absent |
Dissociative fugue is purposeful travel after a severe stressor, with loss of personal identity, a new name taken and amnesia for the episode.
Ganser syndrome gives approximate (near-miss) answers, vorbeireden, with perplexity, hallucinations, clouding and later amnesia, classically in remand prisoners.
ICD-11 places Ganser syndrome under other specified dissociative disorders.
Confabulation and other false recall
Confabulation is the unintentional fabrication of memories to fill an amnesic gap in clear consciousness, as in Korsakoff syndrome; the memories are offered in good faith and are often bland, trivial and shifting.
Confabulation can also be described as genuine memory fragments fused and misordered, then retrieved out of their proper temporal context.
Suggestibility is prominent in confabulation: the person takes up ideas offered by others and reports them as memories.
Confabulation may be spontaneous or elicited, so corroborate without suggestive questioning.
Confidence or inconsistency alone cannot separate memory error from deliberate fabrication.
Phenomenon | What happens | Told apart by |
|---|---|---|
Retrospective falsification | Real events are recoloured by current mood | No gap and no intent to deceive |
Cryptomnesia | A real memory returns without its source and feels original | Content is accurate; only the source fails |
False memory | Confident, vivid recall of an autobiographical event that independent evidence shows never happened | Occurs in a cognitively intact person |
Pseudologia fantastica | Elaborate, fluent, purposeless lying over years | Memory is normal; most strongly linked with factitious disorder |
Paramnesias
Paramnesias are qualitative distortions of memory or of the sense of familiarity, not memory loss, a perceptual or orientation disorder, or delusional misidentification of a person.
Paramnesia | What it is |
|---|---|
Déjà vu | A false sense of familiarity attached to a genuinely new situation, with insight usually kept; occurs in health and in some disorders |
Jamais vu | A transient false sense of unfamiliarity towards something known to be familiar, the reverse of déjà vu, and a recognised temporal lobe seizure aura |
Reduplicative paramnesia | The fixed belief that a familiar place exists in two copies or locations at once, here with a right frontal lesion |
False recognition | An unfamiliar person or place feels familiar |
Language
The bedside language examination covers fluency, comprehension, repetition, naming, reading and writing; episodic memory recall tests a different domain.
Wernicke's area, in the posterior superior temporal gyrus of the dominant hemisphere, subserves comprehension of spoken language.
Broca's area, in the inferior frontal gyrus, subserves production.
Aphasia | Fluency | Comprehension | Repetition | Localisation |
|---|---|---|---|---|
Broca (expressive) | Non-fluent, agrammatic | Relatively preserved | Impaired | Dominant inferior frontal gyrus |
Wernicke (receptive) | Fluent, with paraphasias and neologisms (jargon) | Impaired | Impaired | Dominant posterior superior temporal gyrus |
Conduction | Fluent, with phonemic paraphasias | Relatively preserved | Impaired out of proportion | Arcuate fasciculus |
Anomic (nominal) | Fluent; naming is the leading deficit | Preserved | Preserved | Dominant temporo-parietal junction (angular gyrus) |
Transcortical sensory | Fluent | Poor | Preserved, with echoing | Outside the perisylvian network |
Global | Markedly reduced | Impaired | Impaired | Extensive dominant hemisphere injury |
Broca aphasia is non-fluent, whereas Wernicke, conduction, anomic and transcortical sensory aphasia are fluent.
Preserved repetition despite a clear aphasia points to a transcortical syndrome rather than a perisylvian one (Broca, Wernicke, conduction).
Conduction aphasia differs from Wernicke aphasia by preserved comprehension; transcortical sensory aphasia differs from it by preserved repetition.
Isolated anomia, with fluent speech, circumlocution and intact repetition, comprehension, memory, praxis, calculation and construction, localises to the dominant (left) temporal lobe.
Loss of verbal fluency with preserved comprehension localises to the dominant (left) frontal lobe.
Wernicke-type aphasia, fluent and receptive with jargon and poor insight, is the neurological speech disorder most easily mistaken for schizophrenic speech, so test language systematically.
Selective disorders of reading and hearing
Pure word deafness (auditory verbal agnosia, subcortical auditory dysphasia) is selective loss of spoken word comprehension, with hearing, non-speech sounds, reading, writing and spontaneous speech spared.
In pure word deafness, repetition and writing to dictation fail as a consequence.
Pure alexia (alexia without agraphia, pure word blindness) is selective loss of reading, with speech, spoken comprehension, writing and object recognition preserved, so the patient can write but cannot read it back.
Pure alexia comes with a right homonymous hemianopia from the left occipital lesion.
Pure alexia is a disconnection syndrome: a left occipital lesion extending into the splenium of the corpus callosum cuts visual input from the right occipital cortex off from the left language areas.
The usual cause of pure alexia is infarction in the dominant (left) posterior cerebral artery territory, which supplies left occipital cortex and the splenium.
Alexia with agraphia follows a dominant angular gyrus lesion, within the Gerstmann picture.
Prosody, music and semantic loss
Aprosody is loss of the emotional and melodic aspects of speech and localises to the right hemisphere.
Producing emotional prosody depends on the right inferior frontal region (the non-dominant Broca homologue); recognising it depends on the right posterior superior temporal region.
Receptive amusia follows right (non-dominant) temporal damage, shown by impaired Seashore Rhythm and musical discrimination performance.
Semantic dementia (semantic variant primary progressive aphasia) is fluent speech with loss of word and object meaning, from anterior temporal atrophy, usually left-predominant.
In semantic dementia category fluency falls far more than letter fluency, whereas frontal pathology gives the reverse.
Agnosias
Agnosia is failure of recognition despite intact primary sensation, confined to one modality, with identity available through another route. It differs from apraxia, aphasia, alexia and neglect, and inability only to name may instead be anomia.
Visual agnosia is failure to recognise objects by sight when the visual apparatus, attention and language are intact, while touch still reaches identity.
Agnosia | What fails | What is spared | Lesion |
|---|---|---|---|
Astereognosis (tactile agnosia) | Recognising an object by touch | Primary sensation; the object is recognised at once by sight | Contralateral parietal |
Prosopagnosia | Recognising familiar people by their faces | Vision; identity is reached by voice, gait or clothing | Bilateral occipitotemporal (fusiform) cortex |
Phonagnosia | Identifying familiar voices | Speech comprehension, face recognition | Right temporal and parietal |
Simultanagnosia | Perceiving more than one object or element at a time, so a scene is not grasped as a whole | Acuity, recognition of single objects | Bilateral parieto-occipital, as in posterior cortical atrophy |
Graphaesthesia is recognising a number or letter traced on the skin without looking, a parietal cortical sensory function; failing it is agraphaesthesia.
Disorders of body awareness
Disorder | What it is | Lesion |
|---|---|---|
Autotopagnosia | Failure to locate parts of one's own body on request, while objects in the room are located correctly | Usually left (dominant) parietal |
Hemisomatognosia | The patient feels one half of the body is lost | Usually right parietal, affecting the left side |
Anosognosia | Unawareness or denial of a physical deficit such as paralysis | Typically right hemisphere |
Anosodiaphoria | Awareness of a deficit with striking unconcern about it, often alongside anosognosia | Right (parietal) |
Anton (Anton-Babinski) syndrome | A form of anosognosia: cortical blindness denied by the person, who confabulates visual descriptions | Bilateral occipital cortex |
In Anton syndrome visual loss is total but pupillary light reflexes are preserved.
Apraxias
Apraxia is loss of the ability to carry out a learned, purposeful movement although comprehension, recognition, power, sensation and coordination are intact.
Apraxia | What fails | What is preserved | Lesion |
|---|---|---|---|
Ideomotor | A learned gesture or pantomime of tool use on command or imitation; errors are body-part-as-object, spatial or timing | The same movement occurs naturally, and the real object helps | Usually dominant parietal |
Ideational | The plan for a multi-step sequence of object use, such as folding, inserting, sealing and stamping a letter | Each single action and single gestures | Diffuse disease such as Alzheimer's dementia |
Buccofacial (orofacial) | Voluntary lip, tongue and face movements on command | Automatic use of the same muscles | Often accompanies Broca's aphasia |
Constructional | Drawing, copying or assembling a spatial figure | Perception, motor and sensory function; handling of each component | Non-dominant parietal |
Limb kinetic apraxia is loss of fine limb dexterity in every setting, with no difference between command and automatic use.
Dressing apraxia is inability to match a garment to the body, so it is oriented wrongly; it is typical of non-dominant parietal lesions and often seen with left-sided neglect.
Drawing a figure or assembling a copy is the bedside task that reveals constructional apraxia.
Constructional apraxia is more common and more severe after right hemisphere damage, whereas ideomotor, ideational and orofacial apraxia point to the left hemisphere.
In copying a complex figure, right parietal damage loses the overall configuration while parts survive; left parietal damage keeps the configuration but loses internal detail.
Localisation by lobe
Parietal
Gerstmann syndrome is a fixed tetrad of finger agnosia, right-left disorientation, agraphia and acalculia from a lesion of the dominant (usually left) inferior parietal lobule, at the angular gyrus.
The supramarginal gyrus, next to the angular gyrus in the inferior parietal lobule, produces conduction aphasia and apraxia rather than the Gerstmann tetrad.
Dominant parietal damage gives Gerstmann features, dysphasia, alexia and apraxia; right-left discrimination is a dominant function.
Non-dominant parietal damage gives anosognosia, dressing and constructional apraxia, neglect, disordered spatial attention and topographical disorientation.
Right parietal lesions produce contralateral (left) hemispatial neglect.
Cancellation tasks and line bisection are the bedside tests for unilateral visual spatial neglect, alongside copying and observed daily behaviour.
Parieto-occipital
Balint syndrome is the triad of simultanagnosia, optic ataxia and oculomotor apraxia from bilateral parieto-occipital damage to the dorsal visual stream.
Balint syndrome spares reflex (oculocephalic) eye movements, fields to gross stimuli and ventral stream functions, so lost oculocephalic reflexes point to a brainstem or gaze lesion instead.
Temporal
Klüver-Bucy syndrome follows bilateral anterior temporal and amygdalar damage, with hyperorality, hypermetamorphosis, psychic blindness (visual agnosia), hypersexuality and placidity.
Frontal
Frontal lobe syndrome after traumatic brain injury gives months-long personality and social change, disinhibition, irritability, poor judgement and dysexecutive change, with memory, language and perception spared.
Unilateral anosmia is a localising sign of frontal damage, because the olfactory bulb and tract lie on the orbital surface.
Corpus callosum
Marchiafava-Bignami disease is demyelination and necrosis of the corpus callosum in long-standing heavy drinkers, disconnecting the hemispheres.
Executive function
Executive function, as Muriel Lezak defines it, is the capacity for goal-directed behaviour: volition, planning, purposive action and effective performance.
Executive abilities depend on frontal-subcortical and wider networks, so a single test does not localise a lesion precisely.
Perseveration is inappropriate repetition of the same response to changed stimuli, a marker of organic brain disease, distinct from echolalia, palilalia, logoclonia and verbigeration.
Wisconsin Card Sorting Test
The patient must infer a sorting rule (colour, shape or number) from right or wrong feedback and shift set when the rule changes without warning.
Perseverative errors show poor set shifting and frontal, especially dorsolateral prefrontal, dysfunction.
The test depends on holding a rule in working memory and changing it with feedback, so it is not a pure frontal measure independent of working memory.
Stroop colour-word test
The Stroop test measures response inhibition against interference: the automatic reading of a colour word must be suppressed to name the ink colour.
It is also the standard measure of selective attention, through interference between automatic word reading and effortful colour naming.
Trail Making Test
Part A (numbers only) tests visual scanning and speed.
Part B alternates numbers and letters, adding set shifting, so it is more sensitive to executive dysfunction when read against Part A.
Hayling Sentence Completion Test
The Hayling test has two sections: response initiation, completing sentences sensibly, and response suppression, giving an unrelated word.
Errors in the suppression section reflect failed inhibition of a prepotent verbal response; the Brixton test is published with it.
Other executive tests
Test | Task | What it tests |
|---|---|---|
Go/No-Go | Respond to one cue and withhold on another | Inhibition of a motor response |
Luria fist-edge-palm | Repeat the fist, edge, palm series | Motor programming and sequencing, with order errors and perseveration |
Alternating sequences | Continue a drawn pattern of two alternating shapes | Set shifting; perseveration shows as sliding into one repeated shape |
Letter (phonemic) fluency | Generate words beginning with a letter | Initiation, strategic search, switching and inhibition of rule-breaking responses |
Cognitive Estimates | Answer questions by reasoning from general knowledge rather than recall | Abstraction, planning an approach and checking plausibility; depends chiefly on dorsolateral prefrontal cortex |
Goldstein-Scheerer object sorting | Sort objects into groups | Abstract thinking and concept formation |
The Tower of London test assesses executive function, specifically planning.
The Cognitive Estimates Test is the one to add when apathy, disinhibition and poor judgement suggest frontal dysfunction with preserved memory.
Overinclusive thinking shows on the Goldstein-Scheerer sorting task as groupings that are too broad.
Abstract reasoning is tested by proverb interpretation and similarities, which need a move from the literal or specific to the general category or figurative meaning.
Impaired abstraction shows as concrete, literal answers; performance also depends on language and cultural familiarity.
Frontal Assessment Battery
The Frontal Assessment Battery is a brief, equipment-free bedside screen of several frontal functions, taking about ten minutes.
Use it when a near-normal MMSE coexists with frontal features.
It has six subtests, including similarities (conceptualisation) and the fist-edge-palm series; the Trail Making Test is not one of them.
The prehension subtest elicits a frontal release grasp: the patient grasps the examiner's hands despite being told not to take them.
Tests grouped by lobe
Lobe | Tests |
|---|---|
Frontal (executive) | Verbal fluency, Wisconsin Card Sorting, Stroop, Trail Making B, Category Test |
Temporal (memory and auditory perception) | Benton Visual Retention, Seashore Rhythm, Speech-Sounds Perception, Wechsler Memory Scale, Rey figure |
Parietal | Sensory integration, praxis, Gerstmann-type tests |
Judgement of Line Orientation and facial recognition tests are visuoperceptual tests outside the executive domain.
Judgement of Line Orientation asks the patient to match pairs of lines to a fan of numbered lines, needing only a spoken or pointed answer.
Intelligence and premorbid ability
The National Adult Reading Test (NART) asks the patient to read aloud 50 irregular words, such as aisle or psalm, to estimate premorbid intelligence quotient (IQ).
NART works because irregular word reading depends on earlier vocabulary and resists acquired decline; it is invalid with dysphasia or dyslexia.
The Wechsler Test of Adult Reading is another reading-based estimate of premorbid ability; the WAIS measures current ability.
Premorbid ability is also estimated from education, occupation and development.
A score within population norms may still be a major decline in a previously high performer, and lifelong low scores do not show deterioration.
Raven's Progressive Matrices measures general, fluid, non-verbal reasoning, loading on general intelligence (g), not premorbid ability, executive function or crystallised intelligence.
Raven's is purely non-verbal and relatively culture-reduced, so it suits patients with limited English or dysphasia and comparison across ethnic groups, though scores still rise with schooling.
The Wechsler Intelligence Scale for Children is normed from 6 to 16 years, so it gives full-scale IQ at age 13.
Block design is a timed WAIS-IV core subtest in the Perceptual Reasoning Index (the old performance scale): the patient copies patterns with red and white cubes, drawing on visuospatial construction.
Block design is fluid and falls with ageing, and it helps separate normal ageing from mild cognitive impairment and dementia.
Other neuropsychological tests
Test | Task | What it measures |
|---|---|---|
Rey-Osterrieth Complex Figure | Freehand copy scored element by element, then unannounced delayed reproduction | Copy: visuoconstruction and planning, shown in copying order; recall: visual, non-verbal memory |
Rey Auditory Verbal Learning Test | A list of 15 words over five learning trials, then delayed recall and recognition | Verbal memory dependent on the dominant (left) temporal lobe |
Finger tapping | Tapping, with each hand scored separately | Simple motor speed and lateralised motor slowing |
Rivermead Behavioural Memory Test | Remember a name, a hidden belonging, an appointment and a route; parallel versions | Everyday functional memory, to plan and monitor rehabilitation |
Luria-Nebraska Neuropsychological Battery | Luria's qualitative methods turned into fixed items with objective scoring across clinical scales | Separates brain-damaged from normal performance |
Geriatric Depression Scale | Yes or no answers with few somatic items, suiting poor concentration | Depression lowering cognitive performance in older adults (pseudodementia) |
Global screens such as the MMSE are usually normal in schizophrenia because of a ceiling effect, while tests of attention, processing speed, memory and executive function show marked deficits.
Cognitive screening instruments
Mini-Mental State Examination
The Mini-Mental State Examination (MMSE) totals 30 points, with orientation to time worth 5 and delayed recall worth 3.
It samples orientation, registration, attention and calculation, recall, language and one figure copy, and no item assesses executive function, so a normal MMSE can miss substantial executive problems.
Registration is immediate repetition of three words, repeated until learnt; delayed recall is asked only after serial sevens or spelling has filled the gap.
Serial sevens scores sustained attention and concentration, because the patient must hold and update a running total.
The written command (read, understand and obey) tests language comprehension, whereas naming a pencil and a watch tests expressive word finding.
The three-stage paper command and writing a sentence of the patient's own choosing are also MMSE items.
Copying the intersecting pentagons tests constructional praxis, a visuospatial function dependent mainly on the parietal lobes; a full score needs all ten angles with a four-sided overlap.
Item | Belongs to |
|---|---|
Recalling a name and address | Not the MMSE, which uses three unrelated words |
Naming a public figure | Abbreviated Mental Test Score |
Cube copy, five-word recall | Montreal Cognitive Assessment |
Category fluency | ACE-III |
Addenbrooke's Cognitive Examination III
The Addenbrooke's Cognitive Examination III (ACE-III) scores five domains: attention, memory, verbal fluency, language and visuospatial abilities.
It is scored out of 100, with cut-offs around 82 to 88, and takes about 15 to 20 minutes.
The ACE-III replaced every MMSE item held in the earlier ACE and ACE-R, so no MMSE total can be derived from it.
It was built and validated to detect dementia, not depression, pseudodementia or delirium.
Clock drawing
The clock drawing test samples executive planning, constructional praxis, comprehension of the instruction and visuospatial organisation, but not orientation to time.
It samples visuospatial and executive function together in one brief task, unlike pentagon copying (visuospatial only), motor sequencing (executive only), recall or digit span.
The 5-point score is additive, one point each for circle, number placement, hands present, hands of differing length and the correct time, so a wrong time costs only one point.
Scoring systems vary, so follow a specified method and separate motor from spatial or planning difficulty.
A cognitively intact person with Parkinson's disease draws a well-planned clock with irregular, wavering strokes, because rigidity, bradykinesia and tremor degrade execution rather than planning.
Interpreting results
A normal screen does not exclude impairment, and an abnormal score does not diagnose its cause.
Developmental baseline, education, culture, language, sensory and motor impairment, fatigue, distress, pain, depression, psychosis, substances and effort all alter scores.
Independence in medicines, finances, appointments, cooking and personal care helps separate mild from major neurocognitive disorder.
Refer for neuropsychological assessment when the presentation is focal or atypical, the baseline is unusual, or a specific functional or legal question arises.
Social cognition covers emotion recognition, perspective taking and social judgement, and it is impaired in autism, schizophrenia and frontotemporal disease.