MCB 163 Mammalian Neuroanatomy 01 December 2005 Neurological
MCB 163: Mammalian Neuroanatomy 01 December, 2005 Neurological Basis for Speech and Language Bradley Voytek Helen Wills Neuroscience Institute University of California – Berkeley btvoytek@berkeley. edu http: //socrates. berkeley. edu/~btvoytek
Aphasia Patient “Tan” (Leborgne) • Could answer questions with gestures • Could say a few curse words, “tan” • Broca hoped to disprove cortical specialty • In autopsy, found an abscess in Tan’s brain • 1865 paper showed localization to left frontal lobe (Broca’s area) Pierre Paul Broca
Aphasia Another region? • Not all language disturbances were speech • Not all disturbances involved Broca’s area • Loss of words comprehension • 1874 paper showed localization to left temporal lobe (Wernicke’s area) Carl Wernicke
Broca’s Area
Wernicke’s Area
Speech & Language Regions • Broca’s (BA 44, 45): Inf prefrontal gyrus • Wernicke’s (BA 22): Post sup temporal gyrus at the T-P junction • Arcuate fasciculus: Axon tract connecting Broca’s with Wernicke’s
Brodmann’s Areas
Types of Disorders • Broca’s & expressive aphasias • Wernicke’s & receptive aphasias • Transcortical motor aphasia • Transcortical sensory aphasia • Conduction aphasia • Global aphasia • Subcortical aphasia • Anomia • Alexia • Apraxia
Broca’s Aphasia Nature • True Broca’s aphasia manifests with damage to several areas including: • Broca’s area • Left insula • Left arcuate fasciculus Symptoms • Loss of fluency and articulation • Inability to repeat complex sentences • Impaired comprehension of complex sentences
Broca’s Aphasia
Broca’s Aphasia MRI Video Patient Video • Did you notice his right arm and hand?
Broca’s Aphasia Anterior insula
Broca’s Aphasia (2005) Anterior insula & arcuate fasciculus
Fluent aphasia Wernike’s aphasia Nonsensible speech Not able to comprehend others speech Damage to unimodal association cortex in area 22 • Superior temporal gyrus • •
Nonfluent aphasia • • Broca’s aphasia Agrammatic Telegraphic speech Difficulty using the words: but, if, or, to , from
aphasia Aphasia syndromes Fluency Broca’s nonfluent Intact Impaired LF frontal, insular Transcortical motor nonfluent Intact intact Impaired LF supp. motor nonfluent impaired Impaired LF, wide area Wernicke’s fluent impaired Impaired LF temporoparietal Transcortical sensory fluent impaired Intact Impaired LF parietal, inferior conduction fluent intact Impaired LF arcuate fasciculus, LF parietal, insula anomic fluent intact Impaired LF angular g. global Comprehensio Repetition n Naming region
Paraphasia Often a feature of other aphasias Neologistic • Invention of new words: • ‘glipt’ or ‘crint’ Semantic • Word substitution, similar meaning: • ‘knife’ for ‘spoon’ Phonemic • Sound substitution: • ‘scoon’ for ‘spoon’
Global Aphasia • Damage so widespread is usually caused by MCA infarct
Global Aphasia
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