Cognitive and behavioral neurology Flashcards
Papez circuit
- Hippocampus
- Fornix
- Mammillary bodies
- Anterior nucleus of thalamus
- Cingulate gyrus
- Entorrhinal cortex
Back to hippocampus
Most common genetic cause of early-onset familial AD. Chromosome?
Presenilin-2 (chromosome 1)
Location of cholinergic neuron loss in Alzheimer’s
Nucleus basalis of Maynert
Earliest pathological sign of Alzheimer’s
Amyloid deposition (before plaques and tangles)
FTD variants
- Behavioral variant
- Progressive nonfluent aphasia
- Semantic demantia (aka progressive fluent aphasia)
Gene involved in an AD FTD variant. Chromosome?
Tau, on chromosome 17.
(GRN, another gene nearby on chromosome 17, is also linked to FTD)
Thalamic nucleus that can lead to abulia, anterograde amnesia, and social disinhibition.
Dorsomedial nucleus
(Has connections to dorsolateral prefrontal, orbitofrontal, anterior cingulate, and temporal cortical regions)
Deep brain structure lesion that can lead to akinetic mutism
Bilateral GPi
(GPi is part of anterior cingulate-frontal-subcortical circuit)
(Bilateral frontal lesions can also lead to akinetic mutism)
Chromosome containing huntingtin protein
4
Kluver-Bucy syndrome
- Features
- Associated anatomy
- Associated disease
Localization?
Features
1. Hyperorality
2. Hypermetamorphosis (preoccupied with minute environemental stimuli)
3. Blunted affect
4. Hypersexuality
5. Visual agnosia
A/w bilateral anterior temporal lobes/amygdala
A/w behavioral variant FTD (Pick’s ds), can also be seen other etiologies like HSV encephalitis
FDG-PET finding in DLB
Decreased metabolism in occipital > temporoparietal regions
Pathological finding of silver-staining, spherical tau aggreates in neurons
Pick bodies (seen in Pick’s ds aka behavioral variant FTD)
Memantine mechanism of action
NMDA antagonist
Secondary targets, if any, of donepezil, galantamin, and rivastigmine
All area AChesterase inhibitors
- Donepezil: no secondary target (pure acetylcholinesterase inhibitor)
- Galantamine: also Allosteric nicotinic modulator
- Rivastigmine: also butyrylcholinesterase antagonist
Disease associated with brain pathology of neuropil vacuolization and neuronal loss without inflammation.
CJD
Chromosome containing PRNP and therefore linked to familial prion disease
20p
Inability to recognize faces
Localization if focal
Prosopagnosia
Bilateral fusiform gyri (which are temporo-occipital) - can be seen in AD
(Occipital-parietal flow is “where” process, occipital-temporal flow is “what’ processes)
Triad of Balint’s syndrome
Localization
- Optic ataxia
- Oculomotor apraxia
- Simultagnosia
Bilateral parieto-occipital region (linking vision to spatial regions)
(Occipital-parietal flow is “where” process, occipital-temporal flow is “what’ processes)
Anton Syndrome
Cortical blindness / visual anosognosia
Localization of alexia without agraphia
Dominant occipital (PCA) lesion involving splenium of corpus callosum (preventing visual information from non-dominant visual cortex to reach language areas)
Localiztaion of pure word deafness
Bilatearl middle superior temporal gyri (preventing transmission from auditory cortex to Wernicke’s area)
(Also described with dominant temporal lesions)
Impaired verbal speech production and repetition but preserved written language, with intact verbal comprehension
Localiztion?
Asphemia aka pure word mutism aka verbal apraxia
Localization: dominant frontal operculum (anterior and superior to Broca’s area)
Features of Foix-Chavany-Marie syndrome
Localization?
- Bilateral voluntary control of lower cranial nerves but preserved involuntary and emotional responses (e.g. can’t smile on command, but can smile to joke and yawn)
- Severe dysarthria
Localizatoin: Bilateral anterior operculum
Localization of conduction aphasia
Internal arcuate fasciculus
Localization of transcortical sensory aphasia
Potential ischemic cause?
Inferior dominant temporal lobe (adjacent to Wernicke’s area)
Can be seen with MCA-PCA watershed strokes
Localization of transcortical motor aphasia
Potential ischemic cause?
Dominant frontal regions sparing Broca’s area
Can be seen with ACA-MCA watershed stroke
Name for monotonous speech and inability to vary tone with emotion
Localization
Amelodia or affective motor aprosodia
Nondominant posterior inferior frontal gyrus (similar area to Broca’s but on nondominant side)
(Note that the nondominant correlate to Wernicke’s area leads to sensory or receptive aprosodia, inabilty to perceive the emotional content of other’s speech)
Name for inability to perceive the emotional concent of other’s speech
Localization
Sensory or receptive aprosodia
Nondominant posterior superior temporal gyrus (same as Wernicke’s area but on the nondominant side)
(Note that the nondominant correlate to Broca’s area leads to amelodia aka affective motor aprosodia, inabilty to vary speech tone with emotion)
What type of lesions can lead to pseudobulbar affect?
Lesions that disrupt corticobulbar tracts from cranial nerve nuclei bilaterally
How can a patient recovering from a L MCA stroke develop L hand ideomotor apraxia?
Disconnection syndrome where information from Wernicke’s area is not able to reach R premotor cortex (rare)
Localization of dressing apraxia
R parietal lobe
Localization of behavioral change with socially inappropriate behaviors, facetiousness, innapropriate jocularity, echoproxia, and utilization behavior (mimicking use of objects in the environment)
Orbitofrontal cortex
Localization of behavioral change with apathy and reduced movements and communication
Dorsomedial prefrontal cortex
Localization of decreased planning and judgment, as well as anhedonia.
Dorsolateral prefrontal cortex
What is the Wisconsin card sorting test a measure of?
Prefrontal cortical function
(Subject needs to match cards according to rules but is not told rules, instead is told whether a match is right or wrong.
Capgras delusion
Belief that a person is an identical-looking imposter
Gerstmann’s syndrome
Localization
- Acalcula
- Agraphia
- Finger agnosia
- Left-right confusion
Dominant inferior parietal lobe (dominant angular gyrus) (In inferior MCA division territory)
Where are the frontal eye fields?
Middle frontal gyrus
CSF findings associated with Alzheimer’s
Decreased beta-amyloid_1-42
Increased total and phosphorylated tau
Pathology associated with AD (5)
- Amyloid plaques aka neuritic plaques
- Amyloid angioapthy
- Neurofibrillary tangles
- Granulovacuolar degeneration
- Hirano bodies (intracellular actin aggregates, also seen in CJD)
Disease associated with globose neurofibrillary tangles and tufted astrocytes
PSP
