Week 2- Progressive Aphasias & MEG Flashcards
What is primary progressive aphasia? (According to Mesulam)
-dominant symptom declining language for at least two years (before other symptoms set in)
Discuss progressive non-fluent / agrammatical aphasia (PNFA) in terms of production, comprehension, repetition atrophy and non-verbal deficits.
Production: Non-fluent, hesitant, agrammatic, often phonological errors, often apraxia of speech
Comprehension: Often intact for single words, simple sentences. Impaired for complex sentences.
Repetition: Impaired
Atrophy: Left posterior inferior frontal gyrus (Broca’s area)
Non-verbal deficits: working memory, executive functions
Discuss progressive semantic dementia in terms of production, comprehension, repetition, atrophy and non-verbal deficits.
Production: Fluent but with semantic errors
Comprehension: Impaired
Repetition: Intact
Atrophy: Anterior temporal lobes
Non-verbal deficits: Non-verbal deficits
Object recognition, social cognition, emotional regulation
Discuss progressive logopenic progressive aphasia (LPA) in terms of production, comprehension, repetition, atrophy and non-verbal deficits.
Production: Severe word-finding difficulties, some phonemic paraphasias
Comprehension: Mostly intact for single words and simple sentences, impaired for complex sentences.
Repetition: Usually intact for single words but impaired for sentences and sequences
Atrophy: Left posterior superior temporal gyrus (Wernicke’s area)
Non-verbal deficits: Ideomotor apraxia, calculation difficulties
In logopenic progressive aphasia (LPA), there is ___ in Wernicke’s area but it is not similar to Wernicke’s aphasia in what ways:
atrophy
- patients do not produce many phonological paraphasias and no jargon as in Wernicke’s aphasia
In logopenic progressive aphasia (LPA), there is ___ in Wernicke’s area but it is not similar to Wernicke’s aphasia in what ways:
atrophy
- patients do not produce many phonological paraphasias and no jargon as in Wernicke’s aphasia
SD symptoms do not occur in what type of aphasias?
classic aphasias
Discuss progressive logopenic progressive aphasia (LPA) in terms of production, comprehension, repetition, atrophy and non-verbal deficits.
Production: Severe word-finding difficulties, some phonemic paraphasias
Comprehension: Mostly intact for single words and simple sentences, impaired for complex sentences.
Repetition: Usually intact for single words but impaired for sentences and sequences
Atrophy: Left posterior superior temporal gyrus (Wernicke’s area)
Non-verbal deficits: Ideomotor apraxia, calculation difficulties
Name the three main types of primary progressive aphasia:
- progressive non-fluent / agrammatical aphasia (PNFA)
- semantic dementia (SD)
- logopenic progressive aphasia (LPA)
- ->logos = word, speech (from lego = say), penia = lack of, poverty
Another MEG study: separating semantic and syntactic processing in reading. Are semantic and syntactic processing of sentences carried out by different areas in the brain?
- bilateral, pre-dominantly left, activation in the superior and middle temporal gyri, peaking at 400 ms, was sensitive to semantic anomaly: N400m
- the left dipoles also reacted (somewhat less strongly) to word- class errors and to morpho-syntactic errors ≈ LANm?
- more posterior bilateral, pre-dominantly right, dipoles in the temporal lobe were sensitive to syntactic but not semantic violations
- the syntactic dipoles showed an activation pattern peaking late, between 600 and 800 ms after word presentation: P600m
- as we read at 200–300 ms/word the P600 cannot be a response to single words
- could it be a learning/memory response (~ LAD kicking in)?
Name the three main types of primary progressive aphasia:
- progressive non-fluent / agrammatical aphasia (PNFA)
- semantic dementia (SD)
- logopenic progressive aphasia (LPA)
- ->logos = word, speech (from lego = say), penia = lack of, poverty
Discuss progressive non-fluent / agrammatical aphasia (PNFA) in terms of production, comprehension, repetition and non-verbal deficits.
Production: Non-fluent, hesitant, agrammatic, often phonological errors, often apraxia of speech
Comprehension: Often intact for single words, simple sentences. Impaired for complex sentences.
Repetition: Impaired
Non-verbal deficits: working memory, executive functions
Discuss progressive semantic dementia in terms of production, comprehension, repetition and non-verbal deficits.
Production: Fluent but with semantic errors
Comprehension: Impaired
Repetition: Intact
Non-verbal deficits: Non-verbal deficits
Object recognition, social cognition, emotional regulation
Discuss progressive logopenic progressive aphasia (LPA) in terms of production, comprehension, repetition and non-verbal deficits.
Production: Severe word-finding difficulties, some phonemic paraphasias
Comprehension: Mostly intact for single words and simple sentences, impaired for complex sentences.
Repetition: Usually intact for single words but impaired for sentences and sequences
Non-verbal deficits: Ideomotor apraxia, calculation difficulties
LPA: ____ in Wernicke’s area but patients do not produce many phonological paraphasias and no jargon as in Wernicke’s aphasia
atrophy
SD symptoms do not occur in ___ aphasias
classic
What is an MEG?
Magnetoencephalography (MEG) is a functional neuroimaging technique for mapping brain activity by recording magnetic fields produced by electrical currents occurring naturally in the brain, using very sensitive magnetometers.
In event-related potentials, different responses have been found to be sensitive to different types of
sentence anomalies: the ___ to semantic anomalies, the____ to major syntactic anomalies, and the ____ to local (morpho-)syntactic anomalies
N400, P600, (E)LAN
Another MEG study: separating semantic and syntactic processing in reading. Are semantic and syntactic processing of sentences carried out by different areas in the brain?
-bilateral, pre-dominantly left, activation in the superior and middle temporal gyri, peaking at 400 ms, was sensitive to semantic anomaly: N400m
-the left dipoles also reacted (somewhat less strongly) to word- class errors and to morpho-syntactic errors ≈ LANm?
more posterior bilateral, pre-dominantly right, dipoles in the temporal lobe were sensitive to syntactic but not semantic violations
Another MEG study: separating semantic and syntactic processing in reading. Are different areas responsible for sentence-level syntax based on phrase structure on the one hand and finer tuned syntax based on morpho-syntax on the other?
- the syntactic dipoles showed an activation pattern peaking late, between 600 and 800 ms after word presentation: P600m
- as we read at 200–300 ms/word the P600 cannot be a response to single words
- could it be a learning/memory response (~ LAD kicking in)?
What is apraxia?
inability to perform particular purposive actions, as a result of brain damage.
What is brain atrophy?
a loss of neurons and the connections between them
What is cortical atrophy?
gradual and progressive degeneration of the outer layer of the brain (the cortex) in the part of the brain located in the back of the head (posterior)
First reports of primary progressive aphasia: Arnold Pick (1892):
-a man with progressive aphasia and amnesia, who became mute (Pick’s disease)
First reports of primary progressive aphasia:
Paul Sérieux (1893):
- woman with slow deterioration of word comprehension but without loss of memory or intelligence – first pure case of progressive aphasia
- cortical atrophy in both temporal lobes
First reports of primary progressive aphasia:
Warrington (1975):
-three patients with progressive word- finding difficulties, declining understanding of words and pictures
Pathophysiological processes target ___, cerebro-vascular accidents target areas affected by ____
networks, arteries
MEG version of PMN/N400 study in dyslexia. What was the stimuli?
- auditory sentences presented one word at a time four
- types of ending words:
- correct: When the power went out the room became dark.
- anomalous: When the power went out the room became herrings.
- phonologically similar beginning: When the power went out the room became darling.
- improbable: When the power went out the room became quiet.
MEG version of PMN/N400 study in dyslexia. What was the stimuli?
- auditory sentences presented one word at a time four
- types of ending words:
- correct: When the power went out the room became dark.
- anomalous: When the power went out the room became herrings.
- phonologically similar beginning: When the power went out the room became darling.
- improbable: When the power went out the room became quiet.
MEG version of PMN/N400 study in dyslexia. What were the results?
- dyslexics show abnormal neural responses related to both integration of similarities between the consecutive stimuli and the ability to detect incongruent stimuli
- Semantic priming seems relatively intact in dyslexics, however neural responses to contextual incongruency are delayed
