David W. CarrollPsychology of Language, 5th edition

Introduction Brain Mechanisms and Language Lateralization of Language Processes Evolution of Language

• Language processes from a biological viewpoint

• Two reasons to know about biology of language– Previous discussion • comprehension & production

– Further discussion• Acquisition

• Three sections– Brain Damage related to language– Nature of hemisphere difference– Evolutionary human language

Language is thought to be a mechanism for transmitting the information within thoughts.

One experiment used to demonstrate this idea requires subjects to listen to a short passage of several sentences. The subjects are then asked to repeat the passage. Most subjects accurately convey the gist of the passage in the sentences they produce, but they do not come close to repeating the sentences verbatim. It appears as if two transformations have occurred. Upon hearing the passage, the subjects convert the language of the passage into a more abstract representation of its meaning, which is more easily stored within memory. In order to recreate the passage, the subject recalls this representation and converts its meaning back into language.

http://www.brainconnection.com/topics/?main=fa/evolution-language6

Wernicke’s Area

Broca’s Area

Syndrome Behavioral Deficit Lesion Site(s)

Broca’s aphasia Disturbance of speech production; agrammatic speech; relatively good comprehension

and naming

Frontal lobe adjacent to primary motor cortex

Wernicke’s aphasia Disturbance in auditory comprehension; fluent speech

Posterior portion of first temporal gyrus

Conduction aphasia Disturbance of repetition and spontaneous speech

Lesion in arcuate fasciculus and/or other connections

between frontal and temporal lob

Transcortical sensory aphasia

Disturbance of single word comprehension with relatively

intact repetition

Connections between parietal and temporal lobe

Transcortical motor aphasia

Disturbance of spontaneous speech, with sparing of naming

Subcortical lesions in areas underlying motor cortex

Anomic aphasia Disturbance of production of single words

Various parts of parietal and temporal lobes

Global aphasia Major disturbance of all language function

Large portions of association cortex

syntactic deficit◦ It was the girl who chased the boy. (o)◦ It was the boy whom the girl chased. (x)

Ambiguous sentence◦ The experienced soldiers warned about the

dangers before the midnight raid. (easy)◦ The experienced soldiers warned about the

dangers conducted the midnight raid. (hard)

Dapretto & Bookheimer (1999).

Syntactic Semantic Phonologic tasks

◦ coordination

Ipsalateral pathway Contralateral pathway Corpus callosum Ipsalateral < Contralateral

?

Bever (1980) left hemi – relational processing right hemi – holistic processing

• Subject-Object– The boy kisses the girl.– The girl kisses the girl.

• Tense– The girl is drinking.– The girl will drink.

• Plural noun– The dog jumps over the fence.– The dogs jump over the fence.

Bever and Chiarello (1974)◦ On musical task (non-speech task)◦ Right-ear advantages for the experienced◦ No left-ear advantages

Kaplan and colleagues◦ Difficulty integrating information about

performance with information about character’s relationship.

Word in left visual field◦ Dominant meaning is immediately facilitated, but

not for subordinated meaning.◦ Particular meaning

Word in left visual field◦ Dominant meaning is facilitated immediately, but

inappropriate meaning is not suppressed. ◦ Alternative meaning

Burgess and Simpson (1988)Chiarello (1991)

• Figure from the News and Views summary by Ghazanfar - Chimpanzees are phylogenetically between macaques and humans in the primate lineage, and the similarly 'in between' pattern of their arcuate pathway terminations strongly suggest a gradual evolution of this pathway.(a) Changing patterns of connections between frontal cortical areas and the temporal lobe in humans, chimpanzees and macaque monkeys. AS, arcuate sulcus; CS, central sulcus; IFS, inferior frontal sulcus; IPS, intraparietal sulcus; PS, principal sulcus; PrCS, precentral sulcus; STS, superior temporal sulcus. (b) The voice area in the rhesus macaque relative to other auditory cortical areas and where the voice area would be if it were in a similar location as the human voice area. LS, lateral sulcus; IOS, inferior occipital sulcus; STS, superior temporal sulcus; other labels refer to cytoarchitectonic areal designations. The lateral sulcus is cut open to reveal the superior temporal plane. In this plane, the core region is thought to contain 'primary-like' areas, responding best to pure tones, whereas the surrounding belt areas are more responsive to complex sounds. The voice area in macaques is anterior to the core and belt regions. INS, insula; IT, inferotemporal cortex; Tpt, temporoparietal area.

http://mindblog.dericbownds.net/2008/04/language-evolution-and-arcuate.html