I present evidence that semantic constraints can control language
interpretation even when directly opposed by syntactic cues. We recorded
event-related brain potentials (ERPs) while subjects read stimuli like
1-3.
1. *The pizza had been delivering the ... VIOLATION
2. The man had been delivering the ... ACTIVE CONTROL
3. The pizza had been delivered by ... PASSIVE CONTROL
Stimuli like 1 contain an anomaly at the verb, which is potentially either
syntactic or semantic in nature, depending on the interaction of syntactic
and semantic processing. The syntactic cues in 1 unambiguously indicate an
active-voice analysis and therefore require a logical subject role for the
initial noun phrase. This interpretation is semantically anomalous
(compare to 2). By contrast, a logical object interpretation is plausible.
However, this interpretation requires passive -ED inflection at the verb
rather than -ING (compare to 3). Thus, the syntactic cues in the string
are ill-formed to support this interpretation.
We investigated the interaction of syntactic and semantic processing for
stimuli like 1. Syntax-first models of sentence processing argue that
combinatory semantic processing is preceded and guided by a stage of
purely syntactic analysis (Frazier, 1987; Hahne & Friederici, 1999). This
implies that at the verb in 1, the semantically difficult logical subject
assignment will be pursued, due to support from syntactic cues.
Constraint-based models emphasize the influence of semantic constraints on
language processing (Trueswell, Tanenhaus & Garnsey, 1993). However, much
of the theory and data concerning this issue focus on situations of
syntactic ambiguity, where syntactic constraints are conceivably not at
their strongest. Here we investigate whether semantic constraints can
drive interpretation in the face of unambiguous opposition from syntactic
cues. The hypothesis is that well-formed strings like 1 will be processed
as ill-formed, due to the inconsistency between the verb's inflection and
the semantically driven interpretation.
ERPs at the verb elicited a robust P600 effect for Violation stimuli
relative to controls. No difference in N400 amplitude was observed. The
P600 effect indicates syntactic processing difficulty. The absence of N400
effects suggests that the implausible logical subject interpretation was
not pursued. It appears that semantic constraints can drive the assignment
of thematic roles, even when multiple assignments are logically possible.
Under the conditions observed here, the semantic commitment is so rapid
and entrenched that syntactic cues are rejected when they conflict with
the semantically supported interpretation. In spite of strong syntactic
support for an implausible thematic role assignment, there is no evidence
that the assignment is pursued. Thus, the semantic process observed here
appears to be highly efficient and to exhibit a substantial degree of
independence from syntactic guidance.References
Frazier, L. (1987). Sentence processing: A tutorial review. In M.
Coltheart (Ed.), Attention and performance XII. Hillsdale, NJ: Erlbaum.
Hahne, A., & Friederici, A. (1999). Electrophysiological evidence for two
steps in syntactic analysis: Early automatic and late controlled
processes. Journal of Cognitive Neuroscience 11:2 p. 194-205.
Trueswell, Tanenhaus, & Garnsey (1994). Semantic influences on parsing:
Use of thematic role information in syntactic ambiguity resolution.
Journal of Memory and Language 33 p. 285-318..