Table 2

Some noteworthy potential ‘pitfall’ symptoms and signs requiring further clarification or interpretation in suspected dementia

FeatureClarification/interpretationMajor causes
Ambiguous symptoms
 ‘Poor memory’Often used as a shorthand for ‘cognitive problem’; does it mean episodic memory (events, routes, conversations, etc), semantic memory (words and concepts) or another domain of cognition? If the issue is with memory, is it with encoding information (attention), retaining new information (anterograde memory) or retrieving old information?Any (may have poor episodic memory in dementia with Lewy bodies, frontotemporal dementia, etc, as well as Alzheimer’s disease*)
 ‘Getting lost’Is this truly difficulty completing a route without assistance (topographical disorientation) or wandering (but ultimately getting there)? A useful question can be ‘how would you make your way home from here if you had to do it alone’?Alzheimer’s disease (topography) and behavioural variant frontotemporal dementia (wandering)
 ‘Word-finding difficulty’Often used as a shorthand for ‘language problem’; is it difficulty retrieving the name (very common), loss of vocabulary or difficulty pronouncing the word (uncommon)?Alzheimer’s disease/others (retrieval), semantic primary progressive aphasia (vocabulary) and non-fluent primary progressive aphasia (articulation)
 ‘Lost interest in reading’Is this a general loss of concentration or initiative, anhedonia, difficulty following the plot or a more specific problem tracking lines of text?Alzheimer’s disease (multifactorial) and posterior cortical atrophy (text tracking)
 ‘Doesn’t recognise people’Is this inability to recall their name (personal anomia, common) or to recognise faces or voices, ‘blanking’ familiar people? (true prosopagnosia or phonagnosia, uncommon)Alzheimer’s/others (names), semantic primary progressive aphasia/right temporal lobe atrophy† (familiarity)
 ‘More anxious/irritable’Might be psychiatric (eg, atypical depression) but also an early feature of many ‘organic’ dementiasAlzheimer’s disease, dementia with Lewy bodies, vascular and some frontotemporal dementias (eg, C9orf72 mutations)
 ‘Black sheep of family’Youthful delinquency that contrasts with law-abiding siblingsLatent learning disability, very rarely genetic prion disease
Counterintuitive symptoms
 ‘Asks meaning of words’Loss of ability to understand words in a familiar languageSemantic primary progressive aphasia
 ‘Reads fine print but not the headlines’Visual apperceptive agnosia exposed by non-canonical (eg, very large or pixelated) textPosterior cortical atrophy
 ‘Can play tennis (etc) but can’t find ball on ground’Static visual localisation more impaired than motion vision (or occasionally the reverse), reflecting separable neuroanatomical substratesPosterior cortical atrophy
 ‘Says spouse is impostor’Misidentification delusion (Capgras, etc), can also be for location (eg, asks to go ‘home’ in own house)Alzheimer’s disease, dementia with Lewy bodies
 ‘Much nastier/nicer now’Altered interpersonal awareness and conductBehavioural variant frontotemporal dementia (nasty) and Alzheimer’s disease (nice)
 ‘Become very musical/religious/punctual/good at Sudoku’Enhanced (sometimes loss of) interest/ability in abstract pursuits, usually with loss of interest/affection for other people, on a spectrum of alterations ranging from basic rewards (sweet food and sleep), through sense of humour and timekeeping, to puzzles/complex stimuliBehavioural variant frontotemporal dementia and semantic primary progressive aphasia
Potentially misleading symptoms
 ‘It all started after that…(accident/operation, etc)’Usually, this is attribution bias; occasionally we have seen cases where severe psychological trauma did seem to provoke catastrophic cognitive decline in a previously asymptomatic personAny
 ‘Distant memories are fine’Usually they are not, but highly overlearnt or emotional memories tend to become the focus of cherished anecdoteAlzheimer’s disease
 ‘Poor short-term memory’To a neuropsychologist, this refers to the immediate span of working memory (up to ~30 s) but used colloquially to refer to recent episodic memory of variable spanAny
 ‘Thinks people are stealing from them’Usually not a harbinger of psychosis but a specific delusion of theft (or infidelity)Alzheimer’s disease, dementia with Lewy bodies
 ‘Going deaf’Peripheral hearing should always be checked but in context may signify difficulty understanding word meaningSemantic primary progressive aphasia
 ‘Always been spiritual’Apparent receptivity to ‘ghosts’/presences may signify visual/extracampine hallucinationsDementia with Lewy bodies
 ‘Unexplained aches/pains’Hypochondriasis can occasionally reflect abnormal processing of interoceptive signals such as painRight temporal lobe atrophy and semantic primary progressive aphasia
Signs not to miss/misinterpret
 Bottom apraxiaDifficulty orienting/positioning self in space as when sitting down in a chairPosterior cortical atrophy and corticobasal syndrome
 Closing inPatients overlay their hand or drawing on examiner’s target—feature of organic apraxiaAlzheimer’s disease and posterior cortical atrophy
 ‘(Vicar of) Dibley’ signBinary reversals during conversation—says ‘yes’ but means ‘no’, etcNon-fluent primary progressive aphasia
 Dysprosodia (isolated)Most cases of ‘foreign accent syndrome’ (recognisable as such, sometimes simulated with pantomime exuberance) will be functional, but occasionally patients present with altered prosody and linguistic deficits only supervene (much) laterNon-fluent primary progressive aphasia
 Executive dysfunctionAs used, for example, in neuropsychological reports, it is not synonymous with ‘frontal lobe problem’ but reflects processing across distributed brain networks; moreover, patients with significant frontal lobe dysfunction (as reflected in abnormal behaviour) may perform well on executive testsAny
 Head-turningTo accompanying person, during history taking—lack of confidence/retained awareness of problem/poor memoryAlzheimer’s disease
 Perioral dyskinesiasSubtle trembling movements of lips/lower faceAlzheimer’s disease (younger onset)
 Pigeon signTurns head this way and that, trying to make sense of a picture or visual arrayPosterior cortical atrophy
 Repetitiveness conversingSignifies an organic problem with anterograde episodic memory/accelerated forgettingAlzheimer’s disease
 Semantic paraphasiasSubstitution of related words on a naming task usually will not reflect a primary semantic problem but more likely anomia (impaired word retrieval) with attempted compensationAlzheimer’s disease, others
 Surface dyslexiaSounds irregularly pronounced words as they are printed, due to loss of vocabulary-based readingSemantic primary progressive aphasia
 ‘Thousand yard stare’Sense of unease/threat conveyed by patient who lacks normal social facial microreactivityRight temporal lobe atrophy
 Tie signPatient touches examiner’s tie/face when trying to locate their outstretched hand, due to visuospatial disorientationPosterior cortical atrophy
 ‘Variable deficit’Apraxia is intrinsically variable; organic cognitive impairment of any cause can be impacted by stress or fatigue, and certain entities are characterised by marked fluctuation‡ (sometimes sleep benefit/deterioration), due to seizures, channel dysfunction or impaired dopaminergic/cholinergic switching between brain statesDementia with Lewy bodies (sleep benefit), transient epileptic amnesia (sleep deterioration), inflammatory, immune
  • *Refers to the clinical syndrome of typical (memory-led) Alzheimer’s disease.

  • †Refers to the syndrome associated with right temporal lobe atrophy, within the behavioural variant frontotemporal dementia spectrum.

  • ‡Not the same as inconsistency—organic cognitive fluctuations are internally consistent.