Chapter 9 4 Language cont Brain Language Aphasia

Chapter 9. 4 • Language, c’ont » Brain & Language ◊ Aphasia – Classic localization model ◊ Language in intact brains – ERP studies – Individual differences Study Question. • Compare and contrast Broca’s aphasia, Wernicke’s aphasia, and conduction aphasia 1/9/2022

Brain & Language • Neuropsychology of language <Video clip: Language processing in the brain>

Brain & Language • Neuropsychology of language » Aphasia: Language deficits resulting from brain-related disorders and injury. ◊ Very common – 40 % of all strokes produce some aphasia » Broca’s Aphasia ◊ Paul Broca - studied patient Leborgne (A. K. A. ’Tan’) – – – Treated for leg injury Died a few days later Autopsied brain Discovered ‘Broca’s area’ Left Hemisphere dominance for language

Brain & Language • Neuropsychology of language » Broca’s Aphasia <Video clip: Broca’s aphasia (tono)>

Brain & Language • Neuropsychology of language » Broca’s Aphasia Pierre Paul Broca (1824 – 1880)

Brain & Language • Neuropsychology of language Pierre Paul Broca (1824 – 1880) » Broca’s Aphasia ◊ Production Deficits (expressive or nonfluent) – Problems in producing fluent language – Range from ‘Tono, tono, …’ to short phrases – Lack function words and grammar May retain idioms (‘fit as a fiddle’) or songs – Proximity to motor cortex Dysarthria: loss of control over articulatory muscles Speech Apraxia: Unable to program voluntary articulatory movements.

Brain & Language • Neuropsychology of language Pierre Paul Broca (1824 – 1880) » Broca’s Aphasia ◊ Comprehension deficits (receptive or fluent) – Unable to analyze precise grammatical information <Video clip: Broca’s aphasia - syntactic deficits>

Brain & Language • Neuropsychology of language » Wernicke’s Aphasia ◊ Carl Wernicke, 1870 s – Examined two stroke patients Problems understanding language Fluent but nonsensical speech Poor language comprehension Proximity to auditory sensory areas (Wernicke proposed word memory area) Carl Wernicke (1848 -1905)

Brain & Language • Neuropsychology of language » Wernicke’s Aphasia <Video clip: Wernicke’s aphasia> Carl Wernicke (1848 -1905)

Brain & Language • Neuropsychology of language » Wernicke’s Aphasia Carl Wernicke (1848 -1905) ◊ Production deficits – Sounds fluent (e. g. , foreign language) – Neologistic (invented words) – Semantic substitutions E. g. I called my mother on the television and did not understand the romers by the door.

Brain & Language • Neuropsychology of language » Wernicke’s Aphasia ◊ Comprehension deficits Carl Wernicke (1848 -1905) – Do not recognize the incomprehensibility of their own sentences – Do not comprehend written or spoken language ◊ “Here and gone again” – Aphasia improves over time – Anomia: Losing the ability to retrieve words (nouns)

Brain & Language • Neuropsychology of language » Classical localization model (Lichtheim, 1885; Geschwand, 1967) Conceptual Information Broca’s Wernicke’s

Brain & Language • Neuropsychology of language » Classical localization model (Lichtheim, 1885; Geschwand, 1967) ◊ Damage to main areas – Broca’s Aphasia – Wernicke’s Aphasia ◊ Damage to connections – Transcortical motor aphasia – Transcortical sensory aphasia – Conduction aphasia

Brain & Language • Neuropsychology of language » Conduction aphasia ◊ Damage to the connection between Wernicke’s / Broca’s area <Video clip: Conduction aphasia>

Brain & Language • Neuropsychology of language » Conduction aphasia ◊ Damage to the connection between Wernicke’s / Broca’s area – Arcuate Fasciculus

Brain & Language • Neuropsychology of language » Conduction aphasia ◊ Production deficits – Speech is generally fluent – Problems producing spontaneous speech – Problem repeating speech – Sometimes use words incorrectly – Phonological transpositions (velitision for television) ◊ Comprehension – Can understand spoken/written words – Can hear their own speech errors, but cannot correct them – Oral reading is poor

Brain & Language • Neuropsychology of language » Transcortical motor aphasia ◊ Damage to the area around Broca’s Area – Arcuate Fasciculus & Broca’s uneffected – Lesions go deep into the white matter

Brain & Language • Neuropsychology of language » Transcortical motor aphasia ◊ Production deficits – Articulation is generally fair or good – Problems initiating and organizing speech – Excellent repetition ◊ Comprehension – Can understand spoken/written words

Brain & Language • Neuropsychology of language » A prediction ◊ Disconnecting Wernicke’s from the conceptual area should lead to repetition without comprehension. ◊ Transcortical Sensory Aphasia – Damage to the angular gyri

Brain & Language • Neuropsychology of language » Transcortical Sensory Aphasia ◊ Production deficits – Fluent grammatical speech – Show semantic paraphasia (using the wrong word) E. g. , Apple for orange ◊ Comprehension – Poor comprehension – Repetition without comprehension

Brain & Language • Neurophysiology of language in the intact brain » ERP studies ◊ The N 400: Semantic violations

Brain & Language • Neurophysiology of language in the intact brain » ERP studies ◊ The P 600: Syntactic Positive Shift (syntactic violation)

Brain & Language • Neurophysiology of language in the intact brain ◊ Dispreferred continuation of ambiguous sentences – E. g. , The spy saw the cop with the binoculars Who has the binoculars? “The spy has the binoculars” -> preferred continuation ◊ The N 400 and aphasia – Swaab et al. Patients listened to sentences that had an anomalous word at the end.

Brain & Language • Neurophysiology of language in the intact brain ◊ Swaab et al. (1997)

Brain & Language • Neurophysiology of language in the intact brain ◊ A caveat: Individual differences – Stimulation mapping of the brain Neurosurgery around left hemisphere language areas – A couple hundred of patients – Correlation with effects in Wernicke and Broca’s area are weak Some patients have naming problems in the area, not all. – Anatomical localizations vary considerably.