MORPHOLOGY 2NOV 6, 2015 – DAY 30
Brain & Language
LING 4110-4890-5110-7960
NSCI 4110-4891-6110
Fall 2015
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Course organization• Schedule:
• http://www.tulane.edu/~howard/BrLg/t1-Intro.html#schedule-of-topics
• Today's chapter:• http://www.tulane.edu/~howard/BrLg/t17-LexicalInterface.html
• Fun with https://www.facebook.com/BrLg15/• Quiz before Thanksgiving will be in class & on
Blackboard.
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GradesQ1 Q2 Q3 Q4 Q5 Q6
MIN 6 5 5 4 7 3
AVG 9.0 8.8 8.8 8.4 9.2 7.5
MAX 10 10 10 10 10 10
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THE LEXICAL INTERFACE
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The lexical interface
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Hypotheses
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STS phonological net
p(MTG+ITS)lexical interface
a(MTG+ITS)combinatorial net 1
aIFGcombinatorial net 2
STS phonological net
action words, toolsmotor + somato cortex
a(MTG+ITS)combinatorial net 1 ???
aIFGcombinatorial net 2 ???
imageable wordsmedial temporal gyrus
imageable wordsmedial temporal gyrus
Hickok & Poeppel, symbolic?
Pulvermüller, sensorimotor or embodied
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Summary of lateralization of phonologyLH
fine grained, small window of temporal integration
• high temporal frequency:• rapid cues, like stops
• high spectral frequency: • formants
• categorical distinctions: • lexical, phrasal, clausal
stress;• lexical tone in Thai/Chinese
RHcoarse grained,
large window of temporal integration
• low temporal frequency: • slow cues, like vowels
• low spectral frequency: • fundamental
• graded/coordinate distinctions:• emotional intonation,• sentence type?
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Summary of lateralization of word semanticsLH
fine grained, small window of temporal integration
RHcoarse grained,
large window of temporal integration
a. Slowly selects multiple meanings (divergent processing) that are weakly associated.
b. Primes words that share few semantic features > loosely associated words.
c. Primes the less frequent meaning of an ambiguous word.
d. Primes category, but not others.
e. Priming stays same with more words.
f. Priming is same for unstructured sentences.
g. Priming is same for incongruent sentences.
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a. Quickly selects most familiar or dominant meaning (convergent processing) while suppressing other less closely related meanings.
b. Primes words that share many semantic features > closely associated words.
c. Primes the most frequent meaning of an ambiguous word.
d. Primes function, collectives, goal-oriented classes.
e. Priming is faster with more words.
f. Priming is slower for unstructured sentences.
g. Priming is slower for incongruent sentences.
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A conversion to resolutionLeft hemisphere, fine coding:
9 neurons index 9 regions of space
Right hemisphere, coarse coding:
4 neurons index 12+ regions of space
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Associations for “pig” in LH/RH terms
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What causes the priming effect?Table 9.4
Conditions prime ~ probe Priming effect
1. [–sem, +morph] casualty ~ casual no
2. [+sem, +morph] punishment ~ punish yes
3. [–sem, +morph] successful ~ successor no
4. [+sem, +morph] confession ~ confessor no
5. [–sem, +morph] restrain ~ strain no
6. [+sem, +morph] insincere ~ sincere yes
7. [–sem, +morph] depress ~ express no
8. [+sem, +morph] unfasten ~ refasten yes
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MORPHOLOGY 2
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Dual-route model
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phonological input
/di.paɹ.tɪd/ /wɪnt/
meaning
verb + past tense
morphological analysis
/di.paɹ.t + ɪd/
com
posi
tiona
l rou
te lexical route
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Gow (2012) - Dual lexicons
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MTG appears to be activated by both regular and irregular morphological processes• In English past tense generation and comprehension
tasks both regular and irregular forms have been shown to produce a BOLD response in bilateral pMTG, with most studies showing greater activation in this region by irregular forms than by regular ones.
• Gender in Italian nouns = increased pMTG activation• What gender is a bridge? How about a ship?• il ponte (masc sg)• la nave (fem sg)
• The German plural = increased pMTG activation• Bikini > Bikinis• Mund > Münder
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Numerous studies have shown a dissociation between impairments in regular and irregular morphology
• Aphasia tends to show that frontal lobe damage, particularly damage to the lateral IFG, is associated with deficits in the processing of regular morphology with preserved processing of irregular forms.
• Patients with posterior damage, primarily including the left posterior temporal lobe, may show the opposite pattern, providing a double dissociation.
• For regular inflection, processing seems to require interactions between the pMTG and LIFG.
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ULLMAN ON TWO TYPES OF MEMORY
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Taxonomy of memory
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Declarative memory• comprises the learning, representation, and use of
knowledge about facts (semantic knowledge) and events (episodic knowledge)
• learns relations which are arbitrary• learns gradually, during multiple presentations of a
stimulus and response• is accessible to other mental systems (not ‘informationally
encapsulated’)• at least part of it can be recollected consciously (explicit
memory)
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Procedural memory• comprises the learning, representation and use of
sensorimotor and cognitive “habits”, “skills”, and other procedures, such as riding a bicycle and skilled game playing
• learns inflexible (rule-like) relations in the context of real-time sequences, whether the sequences are serial or abstract, or sensorimotor or cognitive
• learns rapidly, even from a single stimulus presentation• is not influenced by other mental systems (informationally
encapsulated)• applies quickly and automatically, in that a response is
triggered by its stimulus rather than being under conscious control (implicit memory)
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Summary• Procedural memory
• is memory for habits & skills
• learns rule-like relations in a context
• learns quickly, from a single presentation
• is not available to other mental modules (is informationally encapsulated)
• is mostly unconscious (implicit)
• Declarative memory• is memory for facts & events• learns arbitrary relations• learns slowly, from many presentations• is available to other mental modules (not informationally
encapsulated)• is mostly conscious (explicit)
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The declarative/procedural model of language
• The declarative memory system subserves the lexicon• The procedural memory system subserves grammar
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Declarative memory & the lexicon• Stores all arbitrary, idiosyncratic word-specific knowledge,
including word meanings, word sounds, and abstract representations such as word category
• includes representations of simple (non-derivable) words such as cat, bound morphemes such as -ed, irregular morphological forms, verb complements, and idioms
• also contains complex forms and abstract structures that are “regular”
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Declarative memory & the lexicon• Supports a superpositional associative memory, which
allows for generalizations across representations. • For example, the memorization of phonologically similar
stem-irregular past tense pairs (e.g. spring – sprang, sing – sang) may allow for memory-based generalization to new irregularizations, either from real words (bring – brang) or from novel ones (spling – splang).
• This ability to generalize could underlie some degree of productivity within the memory system
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Harry Howard 25LING411, NSCI411/611
Procedural memory & grammar• Underlies the learning of new, and the computation of already-learned, rule-based procedures that govern the regularities of language
• Particularly those procedures related to combining items into complex structures that have precedence (sequential) and hierarchical relations
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Procedural memory & grammar. cont.• Builds rule-governed structure, i.e. the sequential and hierarchical combination – “merging” or concatenation – of forms and representations into complex structures:• syntax (word order)• inflectional and derivational morphology – at least for
default “regulars” but also for irregulars that appear to be affixed
• phonology (the combination of sounds)• compositional semantics (the meaning of the composition
of words into complex structures)
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Final project• Improve a Wikipedia article about any of the topics
mentioned in class or any other topic broadly related to neurolinguistics.
• Write a short essay explaining what you did and why you did it.
• Print the article before you improve it, highlighting any subtractions.
• Print the article after you improve it, highlighting your additions.
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NEXT TIMEMorphology/syntax
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