Cognitive neuropsychology/neurology in theory - a clinical approach 16 th June, 2011 Dr Rupert Noad Department of Neuropsychology, Derriford Hospital,
Post on 23-Dec-2015
219 Views
Preview:
Transcript
Cognitive neuropsychology/neurology in theory - a clinical approach
16th June, 2011
Dr Rupert NoadDepartment of Neuropsychology, Derriford Hospital, Plymouthrupert.noad@nhs.net
MRCPsych Phase IIOlder Persons Mental Health (OPMHS) Module
Making sense of cognition
Watch this video of this woman being interviewed
• What cognitive difficulties is she experiencing?• How can you make sense of these?• Which area of her brain may be being
affected?• What condition might cause this
presentation?
A framework for assessing cognition3 steps:• The questions you ask• Bedside tests• Neuropsychological tests
Domain e.g. memory
Stage 1: Questions for patient/carerStage 2: Observations in the room of amnesia?Stage 3: Informal tests of memory e.g. recent events,
teaStage 4: Bedside cognitive assessments e.g. address
from ACE-R, MMSEStage 5: Formal Neuropsychological assessment e.g.
Camden, WMS
Orientation
Time, place and person.
• time: time of day, date, length of time in hospital• Place: name of building, name of town, hospital• Person: name, age, date of birth.
• Delirium• Post traumatic amnesia• Drug effects• Amnesia – e.g.. Alzheimer's disease• Frontal lobe impairment• General confusion – e.g. unwell• Institutionalisation• Others…..
Memory
• The most common reasons for referral.• Divided into several domains;
• Episodic- personally experienced events.• Semantic- word meaning and general knowledge.• Working Memory- the limited capacity by which
we retain information for a few seconds.
Memory• Amnesia is a severe impairment in memory with intact
perception and intellectual functions
Memory impairments are causes by: Korsakoff's Syndrome • Alcoholic Blackout • Closed Head Injury • Electroconvulsive Therapy (ECT) • Transient Global Amnesia • Encephalitis • Dementia • Temporal Lobe Removals • Hysterical Amnesia
Episodic Memory
• Depends upon the hippocampal-diencephalic system.
• Divided into anterograde and retrograde components.– Anterograde memory refers to the ability to recall newly
encountered information.– Retrograde memory refers to the ability to recall past
events.
Disorders of Episodic Memory
• Generally both anterograde and retrograde memory loss occur in parallel e.g. Alzheimer’s disease or head injury.
• Dissociations occur e.g. hippocampal damage may lead to anterograde amnesia e.g. herpes simplex encephalitis, focal lobe tumours or infarction.
Clinical Clips
• 1.4.4 – what type of memory problem is this man describing?
• 1.4.5 – what about this man?
What are the differences between the two types of problems they report?
Clinical Clips
1.4.4Confabulation (and drifting into irrelevant material)• The falsification of memory occurring in clear
consciousness in association with an organically derived amnesia. It may be:
• Provoked (momentary/fleeting) – evident only on probing, as with this example
• Spontaneous (sustained/grandiose) – evident in general conversation
(this patient was in the acute aftermath of traumatic brain injury)
Clinical Clip: 1.4.5
• Patient had suffered a documented Wernicke’s encephalopathy. He is being interviewed two months after the event. The interview takes place on a Monday in November 1991
Clinical Clips
1.4.5Korsakoffs• Impairment of recall e.g. reasons for
admission/name of prime minster and date of general election
• Preserved alertness and language• Time disorientation, faulty judgment of passage of
time
Other features of Korsakoff’s
• Confirm impairment in new learning on formal testing• Seek to establish length of retrograde amnesia• Confirm other cognitive functions are substantially intact
i.e. a disproportionate loss of memory
Korsakoff’s syndrome is a classic example of a focal persistent amnesic syndrome where memory and new learning are affected out of proportion to other cognitive functions in an otherwise alert and responsive patient. Confabulation is not invariably found
Memory problems arise with damage to• Mammilary Bodies and Dorsomedial Nucleus
of Thalamus (Midline diencephalon) • Medial temporal lobe including hippocampus,
amygdala, connections to surrounding cortex
Assessing memory in clinic
• Specific questions about route to hospital or events on wards
• Recall of a name and address, or 3 items.• Copy and recall of geometric shapes (anterograde
non-verbal memory)• recalling details of past holidays, operations, jobs,
and past homes? (reterograde memory)• vocabulary, names of people, places and things and
general factual knowledge (history, geography, politics, etc)? (semantic memory)
Neuropsychological tests of memory
1. Wechsler Memory Scale – 3rd Edition (1997)2. Adult Memory and Information Processing Battery
(AMIPB) (1985)3. Doors and People Test (1994)4. Recognition Memory Test (1984)5. Camden Memory Tests (1996)6. Rivermead Behavioural Memory Test (2003)
Examples of Neuropsychological testsVerbal Memory - Story Recall & List Learning“Mrs Angela Harper was sitting in her bedroom mending the curtains when
she heard a noise coming from the kitchen. She rushed to investigate and found a boy climbing out of the window with her handbag….”
Visual Memory - Figure Recall
Semantic Memory
• Memory for word meaning, and general knowledge. • Key neural substrate is the anterior temporal lobe• Patients complain of loss of words, may substitute
“thing”• Parallel impairment in understanding meaning of
individual words, beginning with unusual words and progressing onto familiar words.
Disorders of Semantic Memory
• Word finding difficulties are common in both anxiety and ageing but in these cases present as being more variable and not associated with impaired comprehension.
• Semantic dementia is relentlessly progressive and associated with atrophy of the anterior temporal lobe, usually on the left.
Assessing semantic memory in clinic
Does the patient have problems with vocabulary, names of people, places and things and general factual knowledge (history, geography, politics, etc)?
Asking both the patient and accompanying informant to give a memory rating out of 10 may be helpful, amnesic patients less likely to give low scores of 0 or 1 than those with depression or anxiety.
Working Memory
• This refers to the very limited capacity which allows us to retain information for a few seconds
• Uses the dorsolateral prefrontal cortex.• Often appears as lapses in concentration and
attention (going into a room and forgetting the purpose)
Disorders of Working Memory
• Lapses in working memory are common and increase with age, depression and anxiety.
• Diseases which affect basal ganglia and white matter may present with predominantly working memory deficits.
Assessing working memory in clinic
• Days of the week forwards• Days of the week backwards• Months of the year forwards• Months of the year backwards• Serial ‘7’s or ‘5’s or ‘3’s or ‘2’’s• Digit span• Mental arithmetic
Language
Divided into different processes;• Expressive language - production• Receptive language - comprehension• Naming
• Plus reading and writing
Aphasia
• Is an impairment in language • Caused by damage to perisylvian region of left
cerebral hemisphere. • Affects higher language functions - difficulties not
able to be accounted for by impairment in motor systems involved in language production i.e. dysarthria
• Deficits can be revealed by listening to a patient’s recounting of their history
Clinical Clips
• What language abnormalities are being demonstrated in each excerpt?
• 1.3.3• 1.3.2• 1.3.5
1.3.2 Wernicke’s (‘fluent’) aphasia
- Speech is fluent with normal syntax - Lack of meaningful content – reflects defective
appreciation of the meaning of words• Marked impairment of comprehension with fluent paraphasic
speech (incorrectly chosen words, disorganised syntax). • May be appropriate use of articles, pronouns and
prepositions.• Anomia is severe or complete (failure to elicit a naming
response to a stimulus)• Can be increased speech rate and hyperfluency• Lesion affects posterior portion of superior temporal gyrus
and spares anterior speech zone.
1.3.3 Broca’s (‘non-fluent’) aphasia• Difficulty with mechanisms by which words are chosen
and articulated and sentences constructed. • Circumlocution is evident, shown by the patient not
being able to find the correct word and talking around the point using gestures
• Severe restriction of speech output, laborious articulation, short utterances, spared auditory comprehension.
• Restricted vocabulary access• Agrammatism is common• Writing reduced to few common words
Clinical Clips1.3.5• Nominal Dysphasia• Difficulty lies in evoking names at will• improves with cueing, and patient retains knowledge of
what each object is used for. e.g. patient can still use a pen.
• This is one of the commonest manifestations of dysphasia.
Conduction Aphasia
• Damage to the arcuate fasciculus results in conduction aphasia in which a person cannot repeat what is said by another
• Phonemic paraphasic errors predominate, with attempts at self correction
• Single word repetition may be possible, but phrase or sentence repetition is impaired. Particularly for unfamiliar or meaningless items.
• Comprehension and verbal fluency remain intact.
Assessing expressive aphasisa in clinic
• Is the patient as fluent and articulate as normal? Has there been a deterioration in grammar?
• Is there a misuse of words (paraphasias -)? (semantic - clock for watch) or phonemic - baby flitter for baby sitter)
• Is a word-finding difficulty apparent? • Broad responses such as ‘animal’ for ‘camel’ can be
seen in semantic dementia• Notable frequency effect - use less common objects
to test the patient
Assessing receptive aphasia in clinic
• Does the patient have difficulty following complex instructions?
• Does he/she struggle to keep track of group conversations?
• Does he/she find using the telephone particularly difficult? (this is the case for patients with any degree of comprehension deficit, because all the usual gestural and contextual cues to meaning are absent.)
• Is understanding of individual words affected? (as in patients with temporal lobe damage or progressive degenerative diseases)
continued
• Use several common items (coin, pen, key) and ask patient to point to one to assess single word comprehension.
• Test sentence comprehension and syntax commands with common items and commands e.g. “touch the pen” or “if the lion ate the tiger, who remained?”
• Conceptual comprehension (understanding) and semantic store can use same objects. E.g. which item is used to record the passage of time?
Repetition
• Word repetition: Use a series of words of increasing complexity e.g hippopotamus, emerald, perimeter. Listen for phonemic paraphasias.
• Sentence repetition: use well known phrase “no ifs, ands or buts”
Neuropsychological tests of language
• Graded Naming test• Boston Naming Test• Western Aphasia Battery• Vocabulary• Token Test• Description Naming test
Apraxia
• Inability to perform a movement with a body part despite intact sensory and motor function - due to deficits in higher cortical control of movement
• I.e. an inability to carry out a motor command e.g. "act as if you are brushing your teeth" or "salute"
• It can be useful to provide a description of impaired performance, recording both spatial and sequencing errors on different tasks
Apraxia
Also can be:• Ideational - inability to create a plan for or
idea of a specific movement, for example, "pick up this pen and write down your name
• Constructional – inability to draw or construct simple configurations
Other apraxias include:
• Limb kinetic
• Whole body- test by commanding to stand up/turn around
• Dressing- note for muddling clothes and difficulty dressing
Assessing apraxia in clinic
• Imitation of gestures, and gestures to command (e.g. wave, salute)
• Use of imaginal objects (comb your hair, brush your teeth). Common error is to use body part as a tool (e.g. finger for toothbrush)
• Oral apraxia (blow out a candle, stick out your tongue)
• Sequencing task: Luria three step command (fist, edge, palm) or alternating hand movements.
Copyright ©2005 BMJ Publishing Group Ltd.
Kipps, C M et al. J Neurol Neurosurg Psychiatry 2005;76:i22-30i
Figure 1 Hand movements in apraxia. Reproduced from: Goldberg G. Imitation and matching of hand and finger postures. Neuroimage 2001;14:S132-6, with permission from Elsevier.
Visuospatial ability
• Information from the visual cortex is directed towards the temporal or parietal cortex via one of two streams:– Dorsal (‘where’) stream links visual info with
spatial position and orientation in the parietal lobe– Ventral (‘what’) stream links this information to
store of semantic knowledge in temporal lobes
Agnosia
• Agnosia is a ‘loss of ability to recognize objects, persons, sounds, shapes or smells’
• It is particulrly associated with lesions of the left occipital lobe and temporal lobes
• Prosopagnosia is a specific deficit in recognising familiar faces, sometimes even including own
Visual Object Agnosia
• Patient cannot recognise the meaning of visually presented objects
• Recognition sometimes better for real rather than imagined or lined drawings– Apperceptive: patient cannot demonstrate adequate
perception of objects through drawing, copying or matching tasks.
– Associative: drawing or copying tasks bring more success, though performance is “slavish”. More generalised semantic memory impairment.
Prosopagnosia
• Patient is unable to recognise the identity of viewed faces
• Patients can often appreciate the aspects of faces, such as age, gender or emotional expression.
Clinical Clip
1.5.1: Visuospatial agnosia and hemi-neglect• visual neglect shown by omissions in images
copied i.e. the numbers of the clock are crowded onto the right hand side, and one half of the flower is missing.
• This patient had right hemisphere stroke with resulting left-sided hemiplegia
Neglect phenomenaNeglect of extrapersonal spacePatients with focal right hemisphere lesions often fail to
respond to stimuli in the opposite half of extrapersonal space.
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 on the neglected side
Bodily neglectIn its most profound form, patients deny the presence
of hemiplegia despite evidence to the contrary. Less dramatic versions, consisting of a tendency to ignore or under use one side are more frequent.
Bedside tests of visuospatial ability
Neglect• Letter and star cancellation tasks are used.• Object centred neglect patients fail to copy
one side of an object• Copying a 2 headed flower• Line bisection• Clock drawing
Copyright ©2005 BMJ Publishing Group Ltd.
Kipps, C M et al. J Neurol Neurosurg Psychiatry 2005;76:i22-30i
Figure 2 Impaired clock face drawings in dementia.
Visuospatial functioning
• In order for sensations to be fully appreciated and consciously recognised they have to be perceived, discriminated and associated with existing knowledge.
• Stimuli have to be processed (apperception) to from a conscious perception of something
• These conscious elements then need to be associated (linked) with other elements (e.g. memory traces) which give them meaning.
• Abnormality in the higher level process leads to agnosia, a disorder of perceptual recognition (not attributed to a primary sensory deficit or general intellectual impairment)
• Thus perceptual disorders can be subdivided into appreceptive and associative agnosisa
1.5.2• Prosopagnosia (improving)
- inability to recognise faces• Topographical disorientation(this patient has encephalitis)
Assessing visuospatial skills in clinic
DressingDoes patient have an impairment in the ability to dress him/herself? - apraxiaDoes the patient mis-sequence garments when dressing?(sometimes the case
in the context of frontal brain damage).
Constructional abilities - rarely evident without formal testing. For patients with particular skills or professions, is there any complaint of
difficulty drawing or in three-dimensional construction?Has a specific decline been noticed in practical abilities such as DIY or
drawing?
Spatial orientation and route-findingTopographical disorientation 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 a failure to recognize landmarks.
Neuropsychological tests of visuospatial ability• Rey Complex figure• Block Design• VOSP• Benton• BIT• BORB• CVST
Frontal Lobe functioning
• Generally thought to be a (dorsolateral) frontal lobe function, although this set of skills is probably more widely distributed in the brain.
• Impairments relate to planning, judgement, problem solving, impulse control and abstract reasoning.
Disorders of Executive and frontal lobe function.• Head Injury.• Alzheimer’s disease, even in early stages.• The majority of the frontal lobe is subcortical white
matter and the leucodystrophies, demyelination and vascular pathology all cause executive dysfunction.
• Basal ganglia disorders also impair executive skills e.g. progressive supranuclear palsy (PSP).
Clinical Clips
1.7.1• What abnormalities of frontal lobe functioning
are demonstrated and what might account for her different presentation the second time you see her?
Clinical Clip1.7.1• Impaired verbal fluency• Irritability• Disinhibited social behaviour
• Patient had a frontal meningioma• Had surgery - post operative improvement - regained a more
balanced composure and engages in the tests with willingness and humour.
• Verbal fluency remains poor.
1.7.2• Abstract thinking tested with proverb
interpretation i.e. people in glass houses • The patient shows literal/concrete thinking
even with encouragements he cant generalise• Patient had a traumatic brain injury secondary
to severe assault
Exploring executive dysfunction in the clinical interview.• There are a broad range of skills encompassed by “executive
function” so it is worth testing in a number of different ways.• Has there been a drop off in performance at work or in
household tasks and hobbies? (reflecting impairment in sequencing and planning)
• Have any perseverative behaviours been noticed?• Are there any reports of poor judgement or an inability to
modify behaviour according to changing situations.• Appreciation of jokes and puns also depends on complex
abstracting ability and so is frequently affected.
Bedside tests of frontal functions
Memory – learn and recall a name and address with recognitionAttention – arithmetic, digit span
Frontal measures• Verbal fluency – ‘b’ or animals• Proverb interpretation/Similarities • Cognitive estimates• Luria – alternating sequence/spirals• Frontal Assessment Battery (FAB)• Carer report measure – e.g. frontal behavioural inventory
Also focus on the manner of completion – clinical presentation - rather than absolute performance e.g. MMSE
Neuropsychological tests of executive functioningAttentionTEA, Trail Making Test
Working memoryDigit Span/Arithmetic
Executive functioningProverbs/SimilaritiesStroop/Fluency/Trail Making Test, WCST, The Hayling and Brixton
Test
Other domains to think about
• Alexia – reading• Agraphia – Writing• Acalculia- the inability to read, write and
comprehend numbers.• Anarithmetrica- the inability to perform
arithmetical calculations.
For discussion
What about• Eye movements?• Gait?• Frontal release signs?• Rigidity/stiffness/balance?
Are these the role of the psychiatrist/neuropsychologist?
Don’t forget the psychological perspective!
People will often report cognitive problems underpinned by psychological/psychiatric
phenomenon
Mental health difficulties are common in neurological conditions• Eg: in Huntington's Disease
• Depression – 40-50%• Psychosis – 5-15%• Mania – 2%
• Anxiety and obsessions seem to be important
Some symptoms that could accompany the psychological challenge of HD
• Anxiety – palpitations, tightness in throat• Loss/grief – loss weight, increased fatigue, loss
energy, increased restlessness• Low mood – despondency, low motivation,
withdrawal from work, absentmindness/forgetfulness, Inability to concentrate
• Relationship issues - Irritability, anger• Reaction to having HD gene- risky behaviour,
• Cognitive assessment for Clinicians – 2nd Ed (2007). John Hodges (in fact anything by John Hodges)
• Cognitive assessment for Clinicians (2001). Kipps and Hodges (JNNP) Supplement
• Neuropsychiatry and Behavioural Neurology (second Ed). Cummings and Trimble.
Great Resources
top related