Speech And Language Notes

SPEECH and LANGUAGE

-Hearing is crucial for vocal learning and production

-In song birds-deafnesss early in life prevent song learning and production

Areas of brain involved in speech

Wernicke’s area: Understanding written and spoken language

-Traditionally it is Brodmann area 22, found on posterior section of superior temporal gyrus in the dominant cerebral hemisphere (left hemisphere in 95% of right handed individuals and 60% of left handed individuals)

-Area encircles the auditory cortex on sylvian fissure

-Lesion in Wernicke’s area- sensory A PHASIA- person will be able to connect words but will lack meaning

Broca’s Area:

-Region of the frontal lobe of one hemisphere (usually left) with functions linked to speech production

-Brodmann’s area 44, 45

-Motor aphasia: Able to comprehend words and sentences but are unable to generate fluent speech, other problems: fluency, articulation, word-finding, word repetition

Hemispheric specialisation

Left hemisphere: in charge of language functions and logical thought; speech, song, writing

Right hemisphere: controlled by left hemisphere and is responsible for perception of rhythm, spatial-relation skills

-Wada test: injection of sodium pentothal to the blood supply of each hemisphere- if injected on the left side and ask them to read some text and they continue to read but if injected into right and they can’t read- then patient has reversed laterality

All those who answered this question wrote well informed essays; many were quite outstanding with

unexpected evidence of which I was unaware, such as recent evidence for the role of Broca’s area in

linguistic short term memory. I was sad that so many thought that FMRI activations showing where

processing takes place are sufficient to explain how speech is understood or produced. How the named

areas cooperate in a network was hardly discussed, nor was the relationship of language to gesture.

Production of speech

-Speech is produced as a sequence of sounds – 3 stages

-Conceptulisation- speech begins as a pre-verbal message

-Formulation- pre verbal message is converted into linguistic form

-Lexicalaisation:...

Buy the full version of these notes or essay plans and more in our Neuroscience 1 Notes.