Speech and Language Disorders
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Transcript of Speech and Language Disorders
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Disorders of Speech & Disorders of Speech & LanguageLanguage
Dr.B.PRAKASH.Dept of Neurology
PSG Super specialty Hospitals
Coimbatore
26th June 20123rd MBBS Class ; PSG
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Language: OverviewLanguage: Overview• Language is the mirror of higher mental activity.
• It is the communication between persons not only by the speech
• Humans are in higher position than other animals by – Ability to develop & employ verbal symbols for thoughts
through speech, writing etc.,
– Facility of using the hands
• Language have evolved in one particular (Dominant) hemisphere.
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Evolution Evolution
• Higher animals communicate by gesture
• Well developed in chimpanzee (FOXP2 gene)
• FOXP2 – linked to the ability of producing language
• The earliest mode of expression is instinctive pattern
• It is the expression of Joy, fear & anger, body gesture, eye
movement etc.,
– It is represented bilaterally / diencephalon
• Seen in infants / bihemispherical lesions
– This is called paralinguistic form of communication.
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Emotional Vs Language Emotional Vs Language CommunicationsCommunications
• Emotional forms
– Communications of feelings
• Language form
– After cerebral maturation
– Proper education
– Social environmental & cultural factors to be learnt
– Transfers ideas from one to another
– Requires sounds, marks & concepts.
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Speech Vs Language Speech Vs Language
• Language includes – Comprehension, formulation, transmission of ideas
– Needs the use of symbols, sounds, gestures
– To be as per the rules of grammar
– The derangement reflects abnormality of brain –
dominant hemisphere.
• Speech – Refers to Articulatory / Phonatory aspects of verbal
expresion.
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External Vs Inner Speech External Vs Inner Speech
• External speech (exophasy) means, expression of thought by
spoken or written words & the comprehension by others --
continuous activity in human gatherings
• Inner speech (endophasy) is silent process of thought & the
formulation of unuttered word in our mind
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Central Language Zones Central Language Zones
• Four main language areas
– Two are receptive
– Two are executive
– Other areas are also present
• Mainly located in the borders of sylvian fissure
– Perisylvian
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Receptive areasReceptive areas• For spoken language ( Hearing comprehension)
– Postero superior temporal area- Area 22
The posterior part of area 22 : Wernicke’s area
– Heschl’s gyri- Area 41, 42
• For written language (Reading comprehension)
– Angular gyrus – area 39
– Inferior parietal lobe anterior to visual areas.
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Executive Areas Executive Areas • For Motor aspects of speech
– Posterior end of inferior frontal gyrus – Area 44, 45
• Brocas Area
• For writing – Inferior frontal lobe
• Exner’s Area
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Anatomy of Language Functions Anatomy of Language Functions
• Language areas are interconnected by sets of Arcuate fibers
– Visual receptive Parietal Lobe
– Somato sensory Parietal Lobe
– Auditory receptive Temporal Lobe
– Broca’s Area lower Rolandic cortex Speech apparatus
– Exner’s Area Motor apparatus of hand muscles
– Language areas
• Striatum
• Thalamus
• Corpus callosum corresponding minor areas
• No exact margins exists for these areas.
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Cerebral Dominance Cerebral Dominance • Dominance of a hemisphere is important in language functions
• How to decide left side is dominant ?
– Preference for the use of right hand / foot / eye
– Dichoting listening : simultaneously talking different words in each ears
– Loss of speech in left hemispherical lesion
– Arrest of speech by TMS, focal seizures, Stimulus during surgery.
– Wada test: Inj.Na Amytal in to left carotid artery mutism / paraphasia
– Cerebral blood flow during language process (PET / functional MRI)
– After commissurotomy.
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• Anatomic differences between dominant & Non- dominant hemispheres: – Superior surface of temporal lobe is larger – Sylvian fissure is longer – Temporo parietal junction is bulkier
– Occipital horn is larger
• 90% of population is right handed – Decided by hereditary factor
– 99% of right handed have language function on left hemiphere.
• Crossed aphasia (1%)– Aphasia due to right cerebral lesion in right handed.
• Most left handed are forced to become right handed (only hand) – Shifted sinistrals
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Left Handedness Left Handedness • Left handedness may be due to disease
– Birth injury – Childhood trauma – Infantile Stroke
• Aphasia in left handed– Mostly (60%) due to left cerebral lesion !!
• In left handed individuals – 15% have bilateral speech representations – More likely become aphasic easily but mild & brief
• Language capacities of minor hemisphere – Very poor– Feelings, emotions & prosody of speech – Inferior division of left MCA
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Speech & Language Disorders Speech & Language Disorders
• Aphasia / Dysphasia:
– Loss / Impairment of the production & or comprehension of
spoken / written language due to acquired brain lesion.
• Echolalia / Pallilalia :
– Disturbance of speech / Language due to HMF disorders
which causes confusion / delirium / dementia
– Patient repeats the words & phrases whatever he hears
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Speech & Language DisordersSpeech & Language Disorders
• Anarthria / Dysarthria
– A defect in articulation with intact memory /
mental function / comprehension
– Due to motor disorders of muscle of
articulation
• Aphonia / dysphonic :
– Loss of voice due to disorder of the larynx
or its innervations.
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Types of Aphasia Types of Aphasia
• Motor / Broca’s / Anterior / Expressive / Non fluent
Aphasia :
• Sensory / Wernicke’s / Posterior / Receptive /
Fluent Aphasia
• Global / Total Aphasia
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Dissociative Language Syndrome Dissociative Language Syndrome
• Conduction Aphasia
• Word deafness (Auditory verbal agnosia)
• Word blindness (Visual verbal agnosia / alexia)
• Mutism
• Anomia
• Agraphia
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Broca’s AphasiaBroca’s Aphasia
• Deficit in language output / speech production
• Severity varies widely from mildlest to severe forms
• Patient often accept prompting & improve in pronunciation
• Most advanced form of Broca’s aphasia :-
– Loss of all power of speaking
– Not a word can be uttered
• No difficulty in chewing / swallowing / clearing throat / cry / shout
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Broca’s AphasiaBroca’s Aphasia• Can vocalize without words
– Yes / No – Can repeat small sentences – Habitual expressions may present
• Hi, Thank You, good Morning
– Can sing few lines of well known songs – When angered may utter few words.
• Preserved auditory comprehension – Can read – Can purse mouth / blow to commands – Can imitate better than to commands – Self initiated actions may be normal.
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Broca’s Aphasia : Mild forms Broca’s Aphasia : Mild forms
• Able to speak aloud
• Lack of melody
• Words are uttered slowly
• Speech is sparse (15 Vs 100 words/ min)
• Mainly nouns & verbs
• Preposition & conjunctions are omitted
• Telegraphic speech. (Agrammatism)
• Crude communication of ideas
• Repetition is always abnormal (if normal- TCMA)
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Broca’s Aphasia : Mild formsBroca’s Aphasia : Mild forms• Writing is severely affected
• Cannot write / type with left.
• If RUL is normal, cannot express by writing. – Malformed letters – Mispelled words – Dictation impossible – But letters & words may be copied
• Comprehension of spoken / written language – Normal – But found affected if tested stringently
• Naming – Usually affected.
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Mini Broca’s Aphasia Mini Broca’s Aphasia
• Lesion restricted only to Broca’s area (Post part of infr front convulution)
• Loss of motor speech only
• Agraphia
• Comprehension is normal both to
– Spoken language
– Writen language
• Improve rapidly
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Traditional Broca’s AphasiaTraditional Broca’s Aphasia
• Difficulty in understanding
• Mutism
• Agrammatism
• Dysprosody
• Lesions involving
– Inferior frontal gyrus
– Deep white matter between
Broca’s area & motor cortex
– Anterior insula
– Frontal / parietal operculum
– Adjacent cerebrum
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Wernicke’s Aphasia Wernicke’s Aphasia • Impairment of comprehension
– Auditory assn area / their separation from primary auditory cortex
• Fluent but paraphasic speech
– Auditory region
• Inability to repeat spoken / written speech
• Inability to read – alexia
– Visual association area
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Wernicke’s AphasiaWernicke’s Aphasia
• Patient talks volubly
• Gestures freely
• Unaware of his deficit
• Speech is produced without effort
• Sentences are of normal length / intonation
• Devoid of meaning
• Malformed / inappropriate words (paraphasia)
– Literal paraphasia (Phoneme is substituted grass – greel)
– Verbal paraplesia (One word is substituted – grass is blue)
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Wernicke’s Aphasia - Neologisms Wernicke’s Aphasia - Neologisms
• New words with no meaning.
• Jargon speech
– Severe WA, rapid verbal output, abundant paraphasia,
incomprehensible verbalization.
• Word output ( >200 /min) logorrhea – “gibberish”
• Pt constantly searches for correct words
• We cannot understand what is said
• Pt cannot read aloud / silently with comprehension
• The copying is slow.
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Neurological Examination in Neurological Examination in Wernicke’s Aphasia Wernicke’s Aphasia
• Some degree of cortical sensory loss
• Superior quadrantanopia may present
• As no other asstd findings, may be wrongly diagnosed as
psychosis / schizo / dementia
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Global Aphasia Global Aphasia • Due to lesion that destroys large part of language area
• Occlusion of left ICA / MCA (or) ICH / tumor / post ictal
• All aspects of speech are affected – Patient can say only few words or omit only a syllable
– Cannot read / write / repeat
– May understand few words/ participate in common gestures
• As the time passes – Some degree of comprehension
• Associated with – Right hemiplegia / hemianesthesia / hemianopia
• Improvement is better with – edema / post ictal / metabolic deragement, not in infarct.
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Dissociative (disconnection) Dissociative (disconnection) Syndrome Syndrome
• Damage in association pathways – not in cortex
• Conduction aphasia
– Receptive cortex is separated from motor cortex
• Transcortical aphasia
– Perisylvian language areas are separated from
other parts of cerebral cortex.
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Conduction AphasiaConduction Aphasia• The Lesion is at
– Subcortical white matter in upper sylvian fissure
– Supramarginal gyrus
– Wernicks & Broca’s areas are spared
– Arcuate fasciculusArcuate fasciculus is mainly involved
– Temporal lobe around posterior end of sylvian fissure suprasylvian operculum motor associatin cortex ( Broca’s / Exner’s)
• Arterial Involvement – Ascending parietal A
– Posterior temporal branch of MCA.
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Conduction Aphasia Conduction Aphasia • Seperation of auditory & motor areas
without damaging them.
• It mostly resembles Wernicke’s Aphasia – ed fluency / paraphasia / impaired
writing – Speech output is normal.
– RepetitionRepetition is severely affected – Relatively preserved comprehension
• It may resemble Broca’s aphasia – Excellent articulation – Comprehension intact
– Fluency ed
• 15% of aphasia
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Repetition Repetition
• Words Tymp.memb mid ear Inn. Ear Electric
impules Cochlear nucleus medial geniculate body
primary auditory cortex (41,42) Heschles gyrus (in sup.
Temp. gyrus) Wernicke’s area (preliminary decoding) in post
3rd of temporal gyruls Angular gyrus (further processing,
meaning, relations to past experience Broca’s area ( For
repetition, not through angular gyrus) 44,45, in posterior part of
inferior frontal convolution) through arcuate fasciculus Motor
plan transmitted to area 4 to pronounce word Along with
supplementary / BG / Cerebellum sends corticobulbar fibres
brainstem nucles speech sounds
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Pure Word DeafnessPure Word Deafness
• Lesion – Bilateral
– Middle 1/3 of superior temporal gyri
– Connection between primary auditory cortex (41, 42) & assn areas
(22) at supero posterior cortex of temporal lobe.
• Embolic occlusion of small branch of lower division of MCA
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Pure Word Deafness Pure Word Deafness • Impairment of
– Auditory comprehension
– Repetition
– Writing to dictation
• Normal – Comprehension of written language – Self initiated utterances
– Spontaneous writing
• Patient complaints of HOH, but shouting will not help • Audiometry / BEAR – normal,
– Can hear non verbal sounds (door bell)
• Describes words sound like jumble of noises • Patient is forced to depend on visual cues
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Reading Reading • Writing words (visual stimuli) visual cortext ( Area 17)
visual association cortex Angular gyrus (for semantic meaning & integration with other sensory modalities & past experiences.
• To read aloud without meaning the information goes to Broca area without passing thro angular gyrus.
• Broca’s Area Motor speech area Speech
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ReadingReading
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Pure Word BlindnessPure Word Blindness((Alexia without agraphia, visual verbal agnosia)Alexia without agraphia, visual verbal agnosia)
• Literate person loses the ability to
– read aloud
– understand written script
– name colors
– copy words
• There is intact
– Hearing comprehension
– Repetition of heard sentences
– Writing spontaneously / dictation
(but cannot read what has written).
– Conversation.
• He is able to
– spell a word
– Identify a word by having it
spelled to him
– Reading one letter at a time
(letter by letter reading) but
cannot join them ( asyllabia)
• Right hemianopia
Video 1 (2 min)
Video 2 (30 sec)
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Alexia without agraphiaAlexia without agraphia
• Lesion
– Left Visual cortex +
underlying whitematter
( Geniculo
calcarine tract)
– Right Visual cortex
language area connection
(Posterior part of splenium
of corpus callosum)
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Alexia without agraphiaAlexia without agraphia
Rt Lt Rt Lt
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Alexia without Agraphia without Alexia without Agraphia without Hemianopia Hemianopia
• Lesion deep in the white matter at
junction of left occipital lobe –
parietal lobe
– Interrupts projection from visual
cortex to language areas without
involvement of geniculo calcarine
pathways
• lesion in the splenium
• All visual informations reaching
language areas are interrupted.
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Angular Gyrus Syndrome Angular Gyrus Syndrome
• Lesion confined to angular
gyrus / it whitematter
• No hemianopia
• Alexia + Agraphia + Anomia
+ Gerstmann syndrome
(Right –Left confusion,
Acalculia , finger agnosia)
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Pure Word Mutism Pure Word Mutism ( Aphemia, Pure Motor Aphasia of ( Aphemia, Pure Motor Aphasia of
Dejerine)Dejerine)• Injury to dominate frontal lobe • Loss of speech and facio brachial palsy • Can do
– Writing – Comprehension – Read silently with comprehension – Repeat spoken words
• As the patient improves – Speech is audible – Language is intact – No loss of vocabulary / agrammatism – Varying degrees of dysarthria/ anomia /
paraphasia • Lesion
– Lower most part of precentral gyrus – Broca’s area is spared
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Anomic AphasiaAnomic Aphasia(Amnesic aphasia, Nominal Aphasia)(Amnesic aphasia, Nominal Aphasia)
• Some degree of anomia - all language disorders /
confusional states / Dementia
• Without anomia, diagnosis of aphasia is incorrect
• If anomia is the most notablemost notable feature anomic aphasia
• Patient loses only the ability to name people and objects.
• Pauses in speech, circumlocution, substitution, fail to name
• Less frequently used words are more problematic.
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Anomic AphasiaAnomic Aphasia
• When asked to name, tells their use rather than the name
• Can
– use the object correctly
– point when named
– choose from a list of names
• Lesion
– middle temporal convolution
– connection between sensory language areas & Hippocampal
regions ( learning & memory)
• Pathology – Tumor, HSE, abscess, PCA occlusion
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Bilateral Tactile Aphasia Bilateral Tactile Aphasia
• Objects seen could be named
• Could not name those felt in either hand
• Can Describe the objects
• Can tell the letter, digit, verbal materal
• Repetition is intact
• Lesion in connection between cortical sensory areas &
Hippocampal regions (learning & memory)
Cortical Sensory Loss
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Isolation of speech areas Isolation of speech areas ( Transcortical aphasia)( Transcortical aphasia)
• Destruction of border zone between anterior, middle,
posterior, cerebral artery due to ↓ BP, CO poisoning,
anoxia intact language areas but isolated from other
cortex
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Transcortical sensory aphasiaTranscortical sensory aphasia• Impaired comprehension of reading / hearing
• Marked paraphasia, fluent speech, circumlocution.
• Repetition is remarkably preservedRepetition is remarkably preserved (Arcuate fasciculus is preserved)
• Disconnection between auditory language area
from referent centre (Analysis not possible).
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Transcortical Motor Aphasia Transcortical Motor Aphasia
( Anterior isolation syndrome, Dynamic aphasia of Luria)( Anterior isolation syndrome, Dynamic aphasia of Luria) • Comprehension is relatively preserved • Repetition is intact
• Unable to initiate conversational speech
• Agrammatical output • Resembles Broca, but able to repeatResembles Broca, but able to repeat
• Seperation of supplementary motor area with Broca’s area
• Occurs in mild / recovering Broca’s Aphasia / frontal lobe damage
• Asstd Abulia, akinetic mutism
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Writing & Copying Writing & Copying • Language information Motor association cortex
(Superior to Broca’s area) Area 4 Arm & hand.
• Writing to dictation – Wernicke anterior motor areas
• Copying – Visual assn cortex anterior motor areas.
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AgraphiasAgraphias• Writing is an integral part of language function • Disorders of writing reflects all basic language defects • Writing a word is
– By recally its spelling (or)
– By sounding its phonemes & transforming them in to learned graphemes ( motor images)
• In agraphia – Difficulty in transforming phonalogic information into orthographic forms
• Pura agraphia – Rare
– Lesion in the posterior perisylvian area
– Lesion in or near the angular gyrus ( as a part of gerstman)
• Centre – Posterior part of 2nd frontal convolution (Exners writing area)
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Types of AgraphiaTypes of Agraphia• Aphasic Agraphia
– Spelling & grammar errors are abound
• Constructional agraphia – Disturbance in perception of spatial relationship.
– Letters & words are clearly formed but wrongly arranged on the page
– Words are super imposed / reversed / written diagonally / haphazardly / Right left.
• Apraxia agraphia – Language formulation & spatial arrangements are correct
– Hand has lost its skill in forming letters & words
– Scrawling handwriting ; losing its personal character
– Uncertainty about how to the pen is held.
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Subcortical Aphasia Subcortical Aphasia (Thalamic & striato capsular aphasia)(Thalamic & striato capsular aphasia)
• Posterior nucleii of dominant thalamus – MutismMutism – Impaired comprehension – Spontaneous speech is reduced – Rarely fluent speech & jargon – Reading & writing may / may not be affected.
• Ventrolateral thalamic lesion – Able to repeat – Anomia +– Like transcortical sensorytranscortical sensory aphasia.
• Dominant striato capsular Lesion– Caudate head / anterior limb of IC / anterior supr. Putamen.
– Non fluent, dysarthric, paraphasicNon fluent, dysarthric, paraphasic speech
– Difficulty in comprehension, repetition, naming.
– Recovery slow / less complete.
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Approach to a patient with Approach to a patient with language disorderlanguage disorder
• History – Native language
– Handedness
– Level of literacy & education • Ribot’s law
– Polyglots improve quickly in native language
• Pitre’s Law– Language most used before the onset of aphasia will recover first
• Handedness– Hand used to throw a ball, threading a needle, seeing, using spoon,
hammer, saw knife.
• Before testing– Whether patient is alert, can participate reliably
– Other signs of gross cerebral lesion
– Hemiplegia, facial weakness, hemianopia, cortical sensory loss.
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Systematic testingSystematic testing
• 6 aspects of
language fn
– Fluency
– Comprehension
– Repetition
– Naming
– Reading
– Writing.
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Conversational testingConversational testing
– Quick assessment
• Praxis
• Language formulation
• Prosody
• Auditory comprehension
• Fluency
– Sparse laborious speech - Broca aphasia
– Fluent empty paraphasic speech with imparied
comprehension – Wernicke’s Aphasia
– Impaired comprehension with normal reading, speech- pura
word deafness.
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• If no abnormal in conversation other tests
– Reading aloud – pure word blindness
– Writing is disabled in all language abn
– Literal / verbal paraphasia – mild Wernicke’s
– Repeating – Important, ( the complexity) - defective in
perisylvian lesions
– Unable to repeat but comprehension is good – conduction
aphasia.
– Repetition is normal in aphasia – TCM / S Aphasia.
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Management Management • Sudden aphasia great apprehension
• Motor aphasia Depressed
• Sensory aphasia gets angry that his speech is not understood
by others
• As improvement discouragement
• Reassurance & positive speech rehabilitation helps
• Spontaneous improvement occurs over a period ( in stroke)
• Decide for each patient when to start speech therapy usually wait
until one of the language function returns.
• Usually by trained therapist but it benefit is largely psychological.
• Frustration / depression , requires psychiatric evaluation .
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Prognosis Prognosis
• Language disorder due to head injury recovers faster
• Severe Global / Broca / Wernicks – Improve only a little
• Pure word mutism – improves completely & rapidly
• Outcome is favourable for left handed persons
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Disorders or articulation & Phonation Disorders or articulation & Phonation
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