Applied Neurosciences Flashcards
What tests may be used to assess the Frontal lobe?
Similarities:
- Assesses correct categorisation not just similarities between parts
Lexical fluency:
- Category fluency i.e. items bought in a store or animals
- Alphabet fluency i.e. starting with certain letter
- Speed and switching between object set
Cognitive estimates test:
- Uses abstract knowledge
Trial making test:
- Simple type A i.e. 1 - 2 - 3 - 4
- Complex type B i.e. 1 - A
- Good frontal lobe test but as executive however not specific also attention, visuospatial
Luria sequence test:
- Fist - edge - palm
- Requires motor planning, execution and error correction
Others include:
- Alternate pyramids, squares drawing and proverb interpretation
- Frontal release sign and digit span affect too
What are the tests of parietal function?
Copying shapes
- Ability to draw or copy a shape (esp. non-dominant parietal)
Identifying fingers:
- Dominant parietal function - Gerstmann syndrome
- May identify finger with eyes closed or copy examiners hand shape i.e. interlocking fingers
Calculation ability:
- Dominant parietal lobe dysfunction included in Gerstmann syndrome
- Ability to use numbers or copy is inact however arithmetic ability is only dominant parietal lobe
Graphesia:
- Ability to recognise what number is scratched onto someones skin without seeing
- Bilateral parietal lobe funciton
Right left disorientation:
- Dominant parietal lobe dysfunction
Stereognosis:
- Ability to recognise an object without seeing
- Bilateral function due to somatosensory cortices
Two point discrimination:
- Bilateral parietal lobe function due to somatosensory cortices
Visual inattention:
- Hemineglect - feature of parietal lesions
- Letter or star cancellation task, bisection line task or draw a tree/person
How may frontal lobe lesions present?
Unilateral:
- Contralateral spastic hemiplegia
- Slight elevation of mood, increased talkativeness, tendency to joke inappropriately
- Primitive reflexes e.g. suck and grasp
- Anosmia
- Motor speech disorder with agraphia with or without oro-buccal apraxia
Bilateral:
- Bilateral hemiplegia
- Abulia (loss of drive)
- Spastic bulbar palsy
- Decomposition of gait and sphincter incompetence
- Varying combinations of grasping, sucking, utlisation movements
There are specific frontal syndromes too: pseudo depressive illness, dysexecutive and pseudeopsychopathic
What is a gelastic seizure?
Epileptic seizure of left prefrontal cortex that results in uncontrollable laughing
Describe some presentations linked to unilateral and bilateral parietal lobe lesions?
Unilateral:
- Contralateral mild hemiparesis
- Gerstmann’s syndrome (dominant): finger agnosia, right-left disorientation, dyscalculia, dysgraphia)
- Neglect of other side
- Homonomous hemianopia or inferior quadrantopia
- Corticosensory syndrome or sensory extinction
Bilateral:
- Spatial disorientation
- Ideomotor and ideational apraxia (more common with left)
- Anosognosia, dressing and contructional apraxia (more frequent and severe with non-dominant right)
- Tactile agnosia (more common with left)
- Balint syndrome (optic ataxia, oculomotor apraxia, and simultagnosia)
Temporal lobe lesions can present with…
Unilateral:
- Homonymous upper quandrantopia
- Some degree of amusia and/or visual agnosia
- Dysnomia
- Reduced verbal memory
- Wernicke’s aphasia
Bilateral:
- Auditory, visual, olfactory hallucinations
- Disturbances of time perception
- Dreamy states with uncinate seizures
- Korsakoff amesiac defect
- Apathy and
- Hypermetamorphosia (compulsion to attend to all visual stimuli), also hyperorality, hypersexuality and blunted emotional reactivity (Kluver Bucy syndrome)
What is Geschwind syndrome?
Personality change sometimes observed in TLE - may arise from altered white matter tracts
Signs include hypergraphia, hyperreligosity, hyposexuality, circumstantiality and interpersonal viscosity
Name some auras associated with TLE:
Autonomic sensations
- Hypersalivation, gustaroy sensations
Evocation of thought:
- Intrusion of stereotypes words or thoughts
Forced thinking:
- Individual thinking to a certain topic
Psychic seizures
Disturbed perception of time:
- Deja Vu
Panoramic memory:
- Recall of expansive memories in detail +++
Uncinate crisis:
- Taste and smell hallucinations with a lot of detail and reminiscent of the past with altered consciousness
Transient dysphasia:
- L hemisphere in origin
Strong affective experiences:
- Fear or anxiety
Dostoveksys epilepsy:
- Ecastatic sensations in epilepsy
What may unilateral occipital lesions present with?
Contralateral homonomyous hemianopia (central or peripheral)
Homonomymous hemiachromatopsia
Elementary hallucinations (lights colours and indiscrete objects)
Visual object agnosia
Visual hallucinations
If corpus callosum or splenum affected - alexia and a colour naming defect
How may bilateral occipital lobe lesions present?
Cortical blindness (reactive pupil)
Anton syndrome (visual anosognosia and denial of cortical blindness)
Loss of colour perception achromatopsia
Prosopagnosia
Simultanagnosia
Balint syndrome
In Vascular dementia if there is loss of cognitive functioning does a patient retain insight?
Usually
Which orientation is first to go in Delirium?
Time
Poor performance in the Hayling tests indicates?
Inhibition defects
The hayling test an examiner reads out a sentance leaving the last word blank:
- In part 1 subjects finish the sentance
- In part 2 subjects have to say a word unrelated to the sentance
What is alexia without agrahpia?
Impaired ability to read however can still write their own thoughts, understand other speech and speak clearly
Normally affects dominant occipital lobe (left) and posterior corpus callousum (splenium) - subjects may also have right homonymous hemianopia
Name some findings associated with lesions in the following areas:
a) Medial frontal circuit and ACC
b) Dorsolateral prefrontal circuit
c) Orbitofrontal and ventromedial circuit
a) Disruptions in motivation and willful behaviour
Apathy
Abulia
Akinetic mutism
b) Disturbed executive planning (planning, goal directed behaviour and attention)
Perseverative behaviour
Deficits in academic and general intellectual functioning
c) Acquired psychopathy and deficits in social intelligence
Frustration and anger
Disturbances in social functioning, behavioural regulation
What visual symptom is seen in conversion disorder?
Tunnel vision
What is a semantic paraphrasia?
A paraphasia is a substitution
- Semantic means category/meaning therefore may use a different type of fruit
- Phonetic will be the sound “fort” rather than “fork”
What is Ribots law?
That in retrograde amnesia newest memories are first to go, remote memories are the most resistant
What test may be used to differentiate organic coma from a psychogenic one?
Caloric testing - injection of cold water into the external auditory canal
Here normal response is for quick phase nystagmus away from injected site - present in psychogenic coma
In organic coma may get tonic deviation of eyes towards the site injected OR no movement at al
What is a vegetative state?
Unconscious dissociative state of wakefulness without awareness
Eyes open spontaneously
EEG shows sleep-wake cycles
May have stereotyped gestures independent of normal context (yawn, smiling etc.)
If wakefulness this indicates brainstem is working
If lack of awareness indicates cortical dysfunction
What is Broca’s aphasia?
Non-fluent speech and poor repetition but good comprehension (damage to frontal area BA 44 - left inferior frontal convolution)
Where in the brain does the defect for Gerstmann’s syndrome arise from?
Dominant (left) angular gyrus
What is an Argyll-Robertson pupil?
Defect of pupil such that it does not react to light but constricts when looking at closely held objects (accomodation)
Irregular, small and asymmetric in size
Historically from syphillis but also diabetic neuropathy and cataracts surgery
What are neglect syndromes?
Failure to detect visual or tactile stimuli or move limb in contralateral side of body:
- most commonly result from right sided parietal lesions
What is Wallenberg syndrome and its underlying pathology?
Occlusion of posterior inferior cerebellar artery (a branch of the vertebral artery) - causes infarction in the lateral portion of the medulla:
- Dysarthria - damage of ipsilateral palate (CN nerve IX to XI damage)
- Contralateral anaesthesia of body from ascending spinothalamic tract
- Ipsilateral facial numbness (damage of CN V nucleus)
- Horners syndrome (ptosis, meiosis, anhidrosis)
- Ataxia (inferior cerebellar peduncle damage)
- Vestibulocochlear nerve damage - ipsilateral ataxia and nystagmus
Poor score in the seashore musical test could indicate damage to which area of the brain?
Right temporal lobe
Seashore musical test is where individuals have to say if non-verbal sounds are the same (S) or different (D)
Which domain of the WAIS test is used to cognitive design with aging?
Block design
The most common IQ test used in clinical practice is the Wechsler Adult Intelligence scale - what two categories of tests exist and given examples of each?
Verbal:
- Similarities NH
- Arithmetic
- Digit span NH
- Vocabulary H
- Information H
- Comprehension
Performance:
- Picture arrangement
- Block design NH
- Picture completion H
- Digit symbol NH
- Matric reasoning
H - held i.e. should not decline with age - these tests may detect organic illness i.e. dementia
NH - non-held tests i.e these tests decline with age
Outline some tests of set-shifting ability (part of executive functioning)?
Trail making test B
Wisconsin Card Sorting Test
Hayling test - sentence completion
Brixton Task
What does the stroop test assess and which part of the brain is associated with this neuropsychological function?
Response inhibition - frontal lobe
What is the Raven’s progressive matrix?
Test if IQ independent of education and cultural influences - uses visuospatial problem-solving tasks to assess performance IQ
What is the national adult reading test?
Tests previous word knowledge before becoming ill (reading ability seems to be resistant to brain damage) therefore NART may be a good measure for premorbid IQ
What is the Weschler Memory Scale-Revised?
A memory test battery for adults that produces a memory quotient - this is corrected for age and approximates the WAIS IQ.
For memory decline there may be a low MQ but preserved IQ
WMS-R consists of:
- Verbal paired associated
- Paragraph retention
- Visual memory for designs
- Orientation
- Digit span
- Rote recall of alphabet
- Counting backwards
Where in the optic pathway is the defect causing:
a) Unilateral one eye blindness
b) Bitemporal hemianopia
c) Homonomous hemianopia
d) Superior quadrantopia
e) Inferior quadrantopia
f) Cortical blindness
a) Eye itself - retina or macula
b) Optic chiasma
c) Any retrochiasmatic structure (optic tract, lateral geniculate body or optic radiation)
d) Temporal lobe - Meyer’s loop
e) Parietal lobe
f) Occipital lobe
