Major source: Mitchell, D. C. (1994). Sentence parsing.
In M. A. Gernsbacher (Ed.), Handbook of psycholinguistics
(pp. 375-409). San Diego: Academic Press.
Major Issue: autonomy of language subsystems
Autonomous systems (modularity; e.g., syntactic parsing free (initially) of pragmatic, semantic, etc. effects) VS.
Interactive systems (systems not modular;
syntactic parsing influenced (initially) by pragmatic, semantic, etc. effects)
Products of processing (e.g., memory) may reflect
retrieval or representational effects rather than initial
processing (e.g., Sacks effect, Bransford effects)
On-line measures: eye-tracking (word fixation duration),
priming, reading time (moving window)
Current on-line measures are rough measures of processes
that are extremely brief; difficult to determine when systems are in play
(e.g., initial access vs. post-access), so difficult to evaluate modularity
Off-line measures: recognition memory, recall,
Research emphasis on ambiguous sentences (unusual) in
English language; Do results generalize to other unambiguous sentences
and in other languages?
Issue: are all meanings of polysemous words
accessed at comprehension?
Early study: Foss (1970) - phoneme monitoring; longer following ambiguous words suggesting all meanings activated. Effect is very brief; disappears after two syllables.
E.g., The men started to drill before they were ordered to do so.
The sergeant ordered the men to drill before
they were ready to do so.
Much evidence for activation of multiple meanings.
Even a biasing context can fail to restrict multiple activation.
E.g., Swinney (1979) cross-modal priming study:
Hear: Rumor had it that, for years, the government building has been plagued with problems. The man was not surprised when he found several spiders, roaches, and other bugs in the corner of his room.
Lexical decision: bug, spy, sew. Facilitation for bug
and spy immediately, but not after 4 syllables.
Meaning frequency and context may interact:
Duffy et al (1988) eye gaze technique
For balanced (e.g., right) words, both meanings activated when context occurs after word; for polarized (e.g., yarn) only dominant meaning is activated.
When context occurs before word and favors subordinate
meaning, both meanings of a polarized term are activated.
Multiple meanings appear to be activated in many situations
Appears to be automatic process
Ambiguities appear to be resolved during post-access checking.
The cop told the motorist that he had noticed .....
to what is "that he had noticed" attached (complement
structure (VP) or relative clause (modifies motorist)) when it is encountered?
Parsing Possibilities (note similarity with
1. Single structure activated; Garden path model or effect;
Serial processing models (Bever, Fodor); Modularity assumed.
Serial analysis without annotation
Serial analysis with annotation; options are tagged as
possibilities; facilitates later reanalysis if initial choice is incorrect
2. Multiple structures activated;
resource free; no processing costs for multiple structures
resource limited; processing costs
unbiased; all analyses equivalent
weighted; certain analyses are favored
3. Partial analysis; minimal commitment; wait and see;
Assume parsing temporarily suspended until encountering information that resolves ambiguity, at which point analysis runs and completes itself.
While suspended, low-level processing (e.g., NP and PP
assembled) may continue but links (e.g., between NP and PP) are delayed
4. Hybrid models; different strategies in different circumstances.
E.g.: Just & Carpenter: parallel processing if resources
available; serial strategy if overloaded (see Carpenter, Miyake, &
Just, 1995, ARP)
Processing load in ambiguous region; predictions:
Tagged serial = predict slowing
Parallel; resource limited = predict slowing
Serial (no tags) = no difference
Parallel; resource free = no difference
Minimal commitment = faster processing
Results: no processing difference between ambiguous
and matched ambiguous; supports no-tag serial and resource free parallel
Processing immediately after ambiguous region; predictions:
The cop told the motorist that he had noticed to avoid
overtaking the school bus.
*italicized = region after ambiguous region
Serial models = processing difficulty if initial
analysis not supported; no difficulty if initial analysis continues
Parallel models = generally no effect predicted (multiple analyses have been activated)
If weighted, some difficulty if the analysis supported is not the one initially weighted
Minimal commitment = depends on the model's assumptions
about what's maintained in ambiguous region; varying degrees of difficulty
expected as some structure will need to be instantiated.
Strong support for processing increment in disambiguation
region across a number of different domains. For example:
Preposed adverbial clauses (with vs. without commas):
After the young Londoner had visited(,) his parents prepared
to celebrate their anniversary.
Reduced vs. Unreduced relatives:
The defendant (that was) examined by the lawyer turned
out to be unreliable.
Data fail to support unbiased parallel models
Data support untagged serial,
Best support for untagged serial and biased parallel (no
difficulty in ambiguous region, but difficulty in disambiguating region)
Weighted parallel, serial, and some minimal commitment
models must predict initial parsing choices:
1. Strategies based on tree structure analyses
Serial, garden-path analyses; e.g., Frazier (1978)
Late closure: Where possible, attach incoming
material to phrase or clause currently being processed
E.g.: Mike had a date with the sister of the professor
who was named in the newspaper last week.
Late closure - attach relative clause (italicized) to
professor rather than sister
Minimal attachment: attach incoming material
into phrase marker being constructed using the fewest nodes consistent
with the well-formedness rules of the language under analysis
E.g.: The criminal saw the cop with binoculars but the
cop didn't see him.
An extra node is required if the PP (with binoculars)
is attached to the NP (the cop with binoculars) rather than to the VP (the
criminal used binoculars to see the cop).
2. Lexical frame-driven strategies;
No processing tree; rather, lexical properties influence assignment
E.g., Ford, Bresnan, & Kaplan, (1982): Verb frames specify the type of arguments they can take;
E.g., 'positioned' requires object NP and optional PP
"The woman positioned the dress on the rack"
3. Thematic assignment strategies (e.g., Pritchett, 1988; based on Chomsky);
Every NP has thematic role (e.g., agent, patient, goal,
etc.) and parsing is based on the linking of these roles:
e.g., I gave my money to the bookie.
4. Discourse based strategies;
Initial choice based on extent to which interpretation
fits with prior discourse
E.g; I saw the man with the telescope. (Prior discourse might constrain attachment to VP rather than NP)
5. Exposure based strategies;
initial choice based on statistical frequency of comparable structures. For example, in an English corpus most 'that' continuations are complement rather than relative structures; as a result the complement interpretation will usually be the initial choice
E.g: The cop informed the motorist that he had noticed ....
6. General processing cost strategies;
initial choice subject to multiple influences
E.g., Carpenter & Just (1992); high capacity readers
take into account a broad range of potential constraints (lexical, syntactic,
discourse, etc.); while low capacity readers are restricted to most immediate
constraints (e.g., syntactic).
1. Tree structure; consistent support for late closure;
RT for ambiguous NP when new phrase is not connected to current phrase.
As soon as he had phoned his wife started to pack
As soon as he had phoned his wife she started to pack.
But, punctuation and prosody (e.g., comma or pause after
phoned in above) can have a large effect (but shouldn't according to strict
tree structure parser)
Also, some cross-linguistic differences: English displays
late closure tendency but Spanish does not (Cuetos & Mitchell, 1988)
E.g., Someone shot the son of the actress who was on the
balcony with her husband.
English (late closure) attach relative clause to actress;
Spanish speakers tend to attach it to son.
Less support for minimal attachment; sentences requiring nonminimal attachment take longer than controls requiring minimal attachment:
E.g.: Nonminimal attachment: The spy saw the cop with the revolver but the cop didn't see him.
Minimal attachment: The spy saw the cop with the binoculars
but the cop didn't see him.
But: Semantic expectations (spy saw........binoculars)
decrease RT rather than minimal attachment. Nonminimal attachment conforming
to semantic expectations can be faster than minimal attachment that doesn't
conform (Taraban & McClelland, 1988):
The couple admired the house with a friend but knew that
it was overpriced (minimal attachment)
The couple admired the house with the garden but know
that it was overpriced.
2. Lexical frame strategies;
Many results are ambiguous due to difficulty in separating
out initial lexical/thematic effects vs lexical/thematic filtering (revising)
However, some studies have demonstrated instances when
lexical information did not have an immediate effect (lexical effects ignored)
E.g., effects of transitive (saluted) vs. optionally transitive
(fainted)if lexical effects, it should be easier to process material when
lexical item constrains what can follow (saluted), but this does not happen.
Longer Rts for saluted than fainted:
After the private had saluted/fainted the sergeant decided
to end the military drill,
3 & 4. Thematic role assignment and discourse-driven;
Like #2, difficult to determine at what point thematic roles and prior discourse come into play.
5. Exposure-based strategies;
Some evidence that statistical frequency does influence
E.g., Corpus examination:
English - late closure
Spanish - 1st NP attachment
On-line studies support above
However, some disconfirming evidence:
Corpus - NP attachments
On-line - VP attachment (a la minimal attachment)
"I saw the man with the telescope"
Overall: Least ambiguous support for tree structure parsers
and past experience models.
Little known about checking of final sentence structure; there are numerous constraints that must be checked:
number matching between verbs and subjects
thematic role for noun phrase (only one possible)
compatability with discourse
Do checking processes operate without delay?
Are they applied in a consistent order?
Does failure result in starting from scratch?
Emphasis on ambiguous stimuli; ambiguous stimuli make
relevant variables measurable; may not be major problem
Emphasis on English; more of a problem. Want to know about
language processing, not English processing.
Cross-linguistic differences can serve as natural experiment
(e.g., English-Spanish exposure based differences)
Time-frame problem: current methodology makes it difficult
to determine time course unambiguously;