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Ling 411 – 15. Linguistic Evidence for Relational Networks. Linguistic Evidence: Relational Networks. As we have seen, evidence from neuroscience shows that linguistic structure is a network Since the whole human information system is a network Evidence from Neuroanatomy
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Ling 411 – 15 Linguistic Evidence for Relational Networks
Linguistic Evidence: Relational Networks • As we have seen, evidence from neuroscience shows that linguistic structure is a network • Since the whole human information system is a network • Evidence from • Neuroanatomy • Perceptual neuroscience (Mountcastle) • And the linguistic system is part of the overall information system • The same conclusion can be reached from purely linguistic evidence
Language vs linguistic system • What is a language? • Set of texts? • A system underlying texts? • A set or system of processes? • A propensity for learning to speak? • Language vs. dialect vs. idiolect • Conclusion: the term language is too abstract to allow for a clear definition
Alternative: The linguistic system • Easily definable (in contrast to language) • Must be defined in terms of the individual • The linguistic system of an individual • An information system • A neurological system, since it is contained in the brain • Hence, a physical system • Varies from one individual to the next • Can include multiple registers, dialects, languages
Linguistic science and neuroscience • Adopting the view that a linguistic system is a neurological system allows us to build bridges • From neuroscience to linguistic science • We can use the findings of Mountcastle • And findings from neuroanatomy, aphasiology, etc. • From linguistic science to neuroscience • We can provide hypotheses of how the brain works more generally for information processing
Starting from purely linguistic evidence • The structure of the linguistic system of an individual • The system is able to operate • Hence, a fundamental requirement for any theory of linguistic structure: Operational plausibility • For example, it is obvious that the system can process, e.g., words • Comprehension: from speech sounds to meaning • Production: from meaning to speech sounds • Learning: new words can be learned
Operational Plausibility • To understand how language operates, we need to have the linguistic information represented in such a way that it can be used for speaking and understanding • (A “competence model” that is not competence to perform is unrealistic)
Morpheme as item and its phonemic representation What are these? boy b - o - y Symbols? Objects?
Morpheme and phoneme as objectsHow related? Morpheme Phoneme Problem: the morpheme “has” a meaning; the phoneme doesn’t
Alternative view: morpheme and phoneme on different levels As a morpheme, it is just one unit Three phonemes, in sequence boy b o y
This “morphemic unit” also has meaning and grammatical function BOY Noun boy Morpheme b o y
The morpheme as purely relational BOY Noun We can remove the symbol with no loss of information. Therefore, it is a connection, not an object boy b o y
Another way of looking at it BOY Noun boy b o y
Another way of looking at it BOY Noun b o y
A closer look at the segments boy (toy) (Bob) o b y The phonological segments also are just locations in the network – not objects Phonological features
Structure vs. labels BOY Noun boy Just labels – not part of the structure b o y
Objection I • If there are no symbols, how does the system distinguish this morpheme from others? • Answer: Other morphemes necessarily have different connections • Another node with the same connections would be another (redundant) representation of the same morpheme
Objection II • If there are no symbols, how does the system know which morpheme it is? • Answer: If there were symbols, what would read them? Miniature eyes inside the brain?
Objects in the mind? When the relationships are fully identified, the objects as such disappear, since they have no existence apart from those relationships
Quotation from Hjelmslev The postulation of objects as some- thing different from the terms of relationships is a superfluous axiom and consequently a metaphysical hypothesis from which linguistic science will have to be freed. Louis Hjelmslev (1943/61)
Upward and Downward Expression (phonetic or graphic) is at the bottom Therefore, downward is toward expression Upward is toward meaning (or other function) – more abstract meaning network expression
Neurological interpretation of up/down • At the bottom are the interfaces to the world outside the brain: • Sense organs on the input side • Muscles on the output side • ‘Up’ is more abstract
Syntax is also purely relational:Example: The Actor-Goal Construcion Semantic function Syntactic function CLAUSE DO-SMTHG Material process (type 2) Variable expression Vt Nom
Syntax is also purely relational:Example: The Actor-Goal Construcion Semantic function Syntactic function CLAUSE DO-SMTHG Material process (type 2) For example, eat an apple Vt Nom
Narrow and abstract network notation Narrow notation Closer to neurological structure Nodes represent cortical columns Links represent neural fibers (or bundles of fibers) Uni-directional Abstract notation Nodes show type of relationship (OR, AND) Easier for representing linguistic relationships Bidirectional Not as close to neurological structure eat apple eat apple eat apple eat apple
Narrow and abstract network notation Narrow notation Closer to neurological structure Nodes represent cortical columns Links represent neural fibers (or bundles of fibers) Uni-directional Abstract notation Nodes show type of relationship (OR, AND) Easier for representing linguistic relationships Bidirectional Not as close to neurological structure pin pi- -in pin pi- -in
More on the two network notations • The lines and nodes of the abstract notation represent abbreviations – hence the designation ‘abstract’ • Compare the representation of a divided highway on a highway map • In a more compact notation it is shown as a single line • In a narrow notation it is shown as two parallel lines of opposite direction
Abstract and narrow notation • Having two notations available is like being able to draw a highway map to different scales • Narrow notation shows greater detail and greater precision • Narrow notation is closer to the actual neural structures • www.ruf.rice.edu/~lngbrain/shipman
Syntax: Linked constructions TOPIC-COMMENT CL DO--SMTHG Nom Material process (type 2) Vt Nom
Add another type of process THING-DESCR CL BE-SMTHG DO-TO-SMTHG Vt be Adj Loc Nom
More of the English Clause CL FINITE Subj Pred to <V>-ing Predicator DO-TO-SMTHG BE-SMTHG Conc Past Mod Vi Vt be
The downward ordered or ab marked choice unmarked choice (a.k.a. default ) The unmarked choice is the line that goes right through. The marked choice is off to the side – either side
The downward ordered or ab unmarked choice marked choice (a.k.a. default ) The unmarked choice is the one that goes right through. The marked choice is off to the side – either side
OptionalitySometimes the unmarked choice is nothing b unmarked choice marked choice In other words, the marked choice is an optional constituent
Relations all the way • Claim: all of linguistic structure is relational • It’s not relationships among linguistic items; it is relations to other relations to other relations, all the way to the top – at one end – and to the bottom – at the other • In that casethe linguistic system is a network of interconnected nodes
Relationships all the way to..What is at the bottom? • Introductory view: it is phonetics • In the system of the speaker, we have relational network structure all the way down to the points at which muscles of the speech-producing mechanism are activated • At that interface we leave the purely relational system and send activation to a different kind of physical system • For the hearer, the bottom is the cochlea, which receives activation from the sound waves of the speech hitting the ear
Relational networks and operational plausibility • Language users are able to use their languages. • Such operation takes the form of activation of lines and nodes • The nodes can be defined on the basis of how they treat incoming activation
Lines and Nodes in Abstract andNarrow Network Notation As each line of abstract notation is bidirectional – it can be analyzed into a pair of one-way lines Likewise, the simple nodes of abstract notation can be analyzed as pairs of one-way nodes
Two different network notations Narrow notation ab Abstract notation • Bidirectional a b Downward Upward ab b a b f a b
Example: A syllable and its demisyllables:narrow notation, upward direction Node for syllable Nodes for demisyllables Auditory features kin ki- -in
Local Representation: kin(narrow notation, upward direction) This node is unique to kin kiss kin shin ki- -is -in shi-
The Two Directions 1 2 w w
The Two Directions Two Questions: 1. Are they really next to each other? 2. How do they “communicate” with each other? 1 2 w w
Separate but in touch Down Up In phonology, we know from aphasiology and neuroscience that they are in different parts of the cerebral cortex 1 2 w w
Phonological nodes in the cortex Arcuate fasciculus Frontal lobe Temporal lobe 1 2 w w
The ‘Wait’ Element Downward and, downward direction ab Keeps the activation alive w A B Activation continues to B after A has been activated
Structure of the ‘Wait’ Element 1 W 2 www.ruf.rice.edu/~lngbrain/neel
Paradigmatic contrast: Competition A structural detail not shown in abstract notation a b 2 2 For example, /p/ vs. /k/
Paradigmatic contrast: Competition a b a b 2 2