Lecture 11 - Human communication and language

• Wernicke and brocas - mediate language • Somatosensory perception - e.g. braille • Auditory perception • Primary visual pereception • these areas are all connected with wernickes/ brocas to understand and make speech/ language

LOSS OR IMPAIREMENT OF LANGUAGE COMPREHENSION OR PRODUCTION - not a problem with speech/ writing production appartus - due to brain centres

• Broca’s aphasi • Wernickes aphasia • Conduction aphasia • Anomic aphasia

Patient ‘Tan’ - could only say tan • autopsy revealed a large fluid filled cavity in left frontal lobe • could comprehend but not produce speech • speech is associated with left hemisphere

Comprehension is in tact, but speech is slow, non-fluent, costs effort. - Cant produce complete sentence structures - content words still used (nouns/verbs) but - function words are not (a,the,in) so its difficult to follow what they are saying (incomplete sentences)

Damage to INFERIOR LEFT FRONTAL LOBE and UNDERLYING SUBCORTICAL WHITE MATTER • often due to stroke • bottom left

Boston Diagnostic Aphasia test - Cookie theft picture • have to exaplin whats going on in the situation • gets a bit fluid at some points though due to automated phrases

• Agrammatism - difficulty with grammatical constructions, word order • Anomia - trouble choosing/ findings words from memory • Articulation problems - controls muscles speech, mispronunciations of words

• Phrases like yes or no - automatic • Non-language expressions - automatic • curse words- often due to frustrations with language, frontal area damage may also effect planning and organisation, may also inovlve right hem - inhibition and emotional aspects of language

• Patients often have apraxia of the left side - cant follow sequences of motor commands (motor areas near brocas, could also be damaged by stroke) • Damage to motor central areas of left hemisphere -> causes extreme motor impairment (poor writing) • Sensory areas in POSTERIOR BRAIN are usually intact

• 1874 • Have no comprehension of speech - cant repeat back (how you test for this) • Speech it produced but is meaningless, yet fluent and unlabored (just ramble, loads of waffle) • Unaware of condition unlike brocas

• Damage to MIDDLE AND POSTERIOR PORTIONS OF THE SUPERIOR TEMPORAL GYRUS (left hemisphere)

• Pure word deagness - cant recognise spoken word • Comprehension of word meaning - problems understanding, cant give definitions • Inability to convert thoughts into words

CAN recognive other sounds (doorbell) CAN read and write, as well as lip read CANNOT speak sensibly Temporal lobe Auditory system of: Left hem: • recognition of short sounds (words) • For longer sounds (prosody: intonation, rhythm, emphasis, emotional content)

damage to POSTERIOR LANGUAGE AREA (junction of temporal/parietal/occipital) Damage to this area alon causes TRANSCORTICAL SENSORY APHASIA

Caused when POSTERIOR LANGUAGE AREA is damaged: CAN repeat + recognise words CANNOT understand meanings behind repetitions CANNOT form meaningful speech on their own

Pure word deafness + Transcortical sensory aphasia = wernickes - can have them alone, depends on damage

• Visual input to visual center (occipital lobe) • To wernickes area: formulate words • To brocas area: translate signal to motor commands - to muscles, for language expression - Other form of sensory iput goes to sensory association centres (parietal) which then follows same pathway Argued for region specificity, so that in brocas, comprehension is largely fine and vice versa with wernickes

karl lashely - argued its the amount you take out, not where you take it HE WAS WRONG - wernicke proved that there is localisatinon of function

• THALAMUS - where vision terminates, relay station • BROCAS AREA - planing speech, which muscles to mvoe • WERNICKES - sounds put together into speech, and what it means • PARIETAL-TEMPORAL-OCCIPITAL-ASSOCIATION cortex • HIGHER ORDER VISUAL CORTICAL AREAS - forms words

• Imitating/ repeating sounds, following commands • Work on functinos they have retained - depends on ability level • Melodic - improve language skills with music • Alternative Augmentative communication (AAC) - hieroglyphic things (just SR in apes?)

• Apraxia = cant make movements • aphasia = cant speak • alexia = cant read - pure alexia = can write, but not read what you;ve written • agraphia = cant write 3 and 4 normally come together