Anomia Flashcards
Anomia - General Info
Variable lesion sites - typically on the temporo-parietal junction
Primary difficulties :
accessing and retrieving lexical forms
preserved object recognition & object use
Semantic Network - Aphasia
A progressive loss of the ability to remember the meaning of words, faces, and objects with temporo-parietal lobe shrinkage of that area of the brain.
Semantic Network - Dementia
2 Types:
Subordinate: knife to kitchen tool
Visually Related: knife to flat stick
Word Retrieval - Step One
Word node selection from the lexical network
2 Points of breakdown:
- Impaired activation between semantic and lexical networks
- Impaired interaction between lexical and phonological levels
Word Retrieval - Step One - Semantic/Lexical networks
Breakdown:
Impaired activation between semantic and lexical networks
- Weak semantic activation to activate target lexical entry
- No loss of semantic knowledge as in semantic dementia
Examples:
- semantic paraphasia - dog for cat
- No response - errors of omission due to inactivation of word nodes
Word Retrieval - Step One - Lexical/Phonological networks
Breakdown:
Impaired interaction between lexical and phonological levels
- Form (PH) related word errors
- Formal paraphasia
- Phonological feedback to further activate phonologically related words
Example:
- cat to rat to bat
Word Retrieval - Step Two
Errors of phonological coding of lexicon with phonological representations
Likely of phonemic substitution errors
- Sublexical errors - cat to dat
Knows what to say - speaks fluently but no names
Syndrome of Anomia - General Info
Near normal comprehension
Good repetition
Deficits across reading and writing
Syndrome of Anomia - Lexical Features
- Fluent
- Empty with circumlocutions
- Naming gaps/pauses
- Substitution : specific or non-specific words
- Generalized words for specific words
- Proper names/objects are most affected
Neologism - Definition
Nonsense word or words without recognition
Example:
“tilto” for “table”
Neologism - General Info
No conceptual deficit
- good comprehension for written words/pictures
- ability to sort written words into semantic categories
- unable to read correctly
Deficit in speech output lexicon
Involvement of content words
Word finding deficit
Examples of Anomia - Phonosemantic Blends
Erroneous words that share both sound and meaning with the target word
Example:
“broom” for “brush”
Examples of Anomia - Circumlocution
Functional description of the word/object
Example:
It calls people, has numbers = phone
Examples of Anomia - Wernicke
Substitution of vague pronouns
Circumlocutions
Neologism
Examples:
- Mandarin for Seahorse
- Atlas for Globe
Examples of Anomia - Broca
Paraphasias in Object Naming
Examples:
- Telescope for Stethoscope
- Carrot for Asparagus
Primary Progressive Aphasia - General Info
Progressive neurodegenerative condition
Language deficit in absence of any generalized cognitive impairments for at least 2 years
- Gradual onset
- Progressive nature
- No dementia
- Evolves into cognitive and/or behavioral problems consistent with DAT - typically within 5 years
PPA
Multi-modality language deficits - indistinguishable from a single event brain condition
Full awareness with no denial or deficit
Avg. age of onset = 50-55
Family history of dementia
Brain Abnormalities
- 60%
- nonspecific neurodegenerative changes
- 40%
- Alzheimer - NF Tangles
- Pick disease - Tau and Pick bodies
- Creutzfeld-Jacob disease (mad cow disease)
Primary Progressive Aphasia - Types - Expressive
More common type
A disorder of speaking progressing to nearly total inability to speak in most severe stage
Preserved comprehension
Primary Progressive Aphasia - Types - Anomia
Less common type
Begins with impaired word finding
Progressive disorder to comprehension
Preserved articiulation
Common Diseases associated with Anomia - Alzheimer’s Disease
Degeneration to association cortices of frontal, temporal, and parietal lobes, and the hippocampus
Cholinergic deficits in hippocampus and temporal lobe
Caused/Causes:
Neurofibrillary Tangles
Neuritic Plaque
Neurofibrillary Tangles
Twisted and contorted fibers inside brain’s cells
Presence of Tau protein
Collapsed microtubule structure
Neuritic Plaque
Intracellular abnormalities involving the accumulation of amyloid in neuropils
Common Diseases associated with Anomia - Pick Disease
Occurs earlier than Alzheimer’s
Progressive degenerative condition
- frontal/temporal lobes neuronal atrophy = Pick bodies
Inappropriate social behavior, lack of empathy, distractibility, poor hygiene
Receptive and expressive communicative difficulties
Common Diseases associated with Anomia - Creutzfeldt-Jakob Disease
Similar to Mad Cow disease
Neurodegenerative disorder
- Brain becomes spongey/hole-y
Lifespan after diagnosis = 1 year on avg.
Causes:
- Ataxia
- Gait abnormality and dysarthria
- Mood changes
- Cognitive impairments
- Seizures
- Myoclonus
Infectious spongiform encephalopathy of animals
Average Age per Aphasia Type
Broca -
Youngest at Avg. age of 52.6
Wernicke -
Oldest at Avg. age of 62.8
Subcortical Aphasia - General Info
Debate over existence
CT - PET evidence
- implicating cortical symptoms from subcortical lesions
Below level of neocortex - inter cranial pressure causes the aphasia
Subcortical Aphasia - Theories & Evidence
Theories of Thalamic Functions
- Internal activating system
- Regulator for semantic accuracy - Crossen
Lesion Evidence
- Hemorrhage
- Thalamotomy
- Stimulation
Thalamic Syndrome
Present with anomia and aphonia
Sensorimotor Symptoms:
- Hemiplegia
- Hemianesthesia
- Hemianopsia
- Altered consciousness
- Coma
- Lowered/Increased pain threshold
Thalamic Aphasia
Symptoms not similar to cortical aphasias
Impaired spoken language
- Aphonia
- Dysarthria
- Anomia
- paraphasias leading into jargon
- semantic aphasias
Preserved comprehension
Good repetition
Reading & writing disorders are variable
Complete recovery within 4-5 weeks
Hemorrhage vs. Embolic stroke
Hemorrhagic stroke has a higher rate of fatality, however if you survive the stroke the recovery is much easier
Reading & Writing
Symbolic skills
Neural dependence on auditory-verbal modality
Two different components: Reading - visual system Writing - visual and motor-kinesthetic systems
Deficits in these areas cause:
Alexia and Agraphia
Alexia - Phonemic Rules
English Phonemic rules:
Acceptable words - boy and toy Acceptable psedo-words - felp or blix Unacceptable strings - bdaxyn Irregular words - knife, judge
Alexia - Strategies for Reading
Two Types:
Phonological reading
- grapheme-phoneme mapping
- single unit conversion
- used for universal reading
Lexical reading
- accessing meaning through an orthographic representation
- used for irregular words
Phonological Reading
Grapheme-phoneme conversion for:
- familiar words
- pronounceable (pseudo) words
- conversion of written to spoken words
- phonological representations : basis for the abstraction of reading
Limitations:
- Foreign words
- Irregular words
Lexical Reading
In this type of reading one pays attention to the entire orthographic representation (word)
Lexical/Semantic based system of orthographic representation for:
- unfamiliar words
- foreign words
- irregular words
- familiar words
A written word association with a visual word (orthographic representation in lexical memory
Common Aphasic Alexias
Alexia with Agraphia
Alexia without Agraphia
Deep Dyslexia
Phonological Alexia
Suface Alexia
Oriental Alexia
Alexia with Agraphia
Inability to read or write
- involves letters, words, musical signs, and numbers
- some processing of signs and Roman/Arabic numerals
- Preserved word copying ability
Largely part of Wernicke’s
Cues are of little to no help because it is a central disorder
Right hemiplegia and visual field deficit
Alexia without Agraphia
Inability to read, but can still write
No alexia for grapheme (can’t read the whole word, but can read individual graphemes)
Recognition for spelled words
Letter by letter reader
Right visual field difficulty
Deep Dyslexia
Involves both routes:
- relative loss of grapheme/phoneme conversion system
- relative loss of lexical route
Reading deficit marked by
- preserved derivation of meaning from whole word
- ex. Can’t read the word, but they can get the meaning
- Semantic paralexia
- ex. When reading they will replace the word
- Omission or misreading of grammatical/functional words
- ex. Better reading of nouns than verbs/adjectives
- Poor ability to select a word from semantically related category of words
- ex. rose from list of flowers
- Poor matching of homophonic words
- ex. flour/flower
- No reading of non-words
Examples of Errors: Nouns - night for sleep Verbs - shining for sun Articles - the for is Visual - bush for brush
Phonological Alexia
Loss of the grapheme to phoneme route
Reliance on lexical-phonological route (reading of known words)
No paralexic errors
No reading of non-words
Suface Alexia
Loss of the lexical to semantic route
Reliance on the grapheme-phoneme route
No recognition of whole words
No access to meaning on a whole word basis
Access to words by sounding through grapheme/phoneme mapping
Superior reading of regular words and legitimate non-words
No reading of irregular words
Oriental Alexia
Only applies if you’ve live in China/Japan
Japanese : Two types of Graphic Systems
- Kanji - ideographic symbols
- parietal-occipital area
- Kana - phonemic system
- parietal-temporal area
Agraphia - General Info
Impaired ability to write
Mental association between letter names and graphic movements
Oral spelling via phoneme-grapheme associations and associations between concepts and letter strings:
- Generally writing and verbal skills are parallel, but not always
- Same aspects of spoken language affect writing (Broca’s and Wernicke’s types of aphasics)
Agraphia - Effects
Disturbed motor-kiesthetic function
- quality of writing
- size
Linguistic aspects
- Graphic-phonemic association
- Orthographic spelling
- Selection of graphic representations of words
- Writing of irregular words
- Semantic and syntactic organization
Visual-Spatial functions
- Disordered size relationship
Apraxic Agraphia
Inability to use a writing tool to form graphic symbol even when a model is presented - have a problem with the tool more than the substance
Isolated component of ideational apraxia
- All purposeful movements or as a result of constructional apraxia
- failure to form letters even in copying
- better ability to spell with anagram letters
Deep Dysgraphia
A broken link between word meaning and written word forms
Spelling errors:
- semantically related with no phonological resemblance
- ex. smile/laugh
Better writing of concrete nouns
Impaired ability to write grammatical words
Phonological Agraphia
Impaired conversion of phonemes into graphemes
Can write read words
Can’t write non-words
Visual errors contain resemblance to the target word
Surface Agraphia
Correlated with surface alexia
Makes phonemic/phonetic spelling errors
- ex. Sirkal for circle
Preserved writing of non words
Angular Gyrus
Crossroad between written and oral language
No spelling, recognition of oral spelling, or retrieval of graphic form from a string of letters.
