Neurological Basis for Speech and Language 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 Symptoms 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

LF arcuate fasciculus, LF parietal, insula aphasia Aphasia syndromes Fluency Comprehension Repetition Naming region Broca’s nonfluent Intact Impaired LF frontal, insular Transcortical motor intact LF supp. motor global impaired LF, wide area Wernicke’s fluent LF temporo-parietal Transcortical sensory LF parietal, inferior conduction LF arcuate fasciculus, LF parietal, insula anomic LF angular g.

Paraphasia Neologistic Semantic Phonemic 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