Connectionist Modeling of Experience-based Effects in Sentence ...

2.5 Forgetting Effects SHORT-TERM FORGETTING 18
Reading time [ms]
400 600 800 1000 1200 1400
Experiment 2 (English Eyetracking): grammaticality
grammatical
ungrammatical
V3 V2 V1 Post!V1
Region
Figure Figure 6. 2.6: Mean Effect reading of the times grammaticality and 95% confidence manipulation intervals for inthe theverb English and post-verbal eyetracking regions study
inby theVasishth English eyetracking et al. (2008) study (experiment 2). 2, The p. 18): figureMean shows reading the effecttimes of the grammaticality
and 95% confi-
manipulation. dence intervals for the verbs and post-verbal regions.
addition, Germaninreaders the SPRdodata not seem we found to forget weak the evidence VP prediction. consistent with In fact thethey NP-forgetting seem to notice hy-
the pothesis, ungrammaticality but in the eyetracking of the drop-V2 data wecondition, found stronger which evidence leads to forincreased NP forgetting. reading time.
The surprising result points to the assumption that linguistic memory processes are not
One surprising result in the eyetracking data was the shorter re-reading time at V3
language-independent but rather affected by language-specific grammatical properties.
in the ungrammatical condition. However, this effect can be explained. Re-reading time
The head-finite nature of German (SOV) subordinate clauses causes verbs to appear
is a function of revisits or regressions to regions that have already been viewed during the
clause-finally more frequently than it is the case in English, an SVO language. An ob-
first pass. Given that regressions are more frequent in complex sentences (where complexity
jection
is defined
might
as increased
be, that commas
ambiguity
in
(Clifton
German
et
facilitate
al., in press)
the recognition
or any other
of
kind
a completed
of integration
clause.
Adifficulty), double-embedding and given that involves the ungrammatical a comma aftersentences each embedded are predicted main to verb. be less Vasishth complex and
colleagues overall, it addressed is not surprising this issue that byre-reading a fifth experiment time is shorter involving at V3 English in thesentences ungrammatical enriched
with condition. commas. However, the comma inclusion did not show any effect. Nevertheless, as
Vasishth et al. note, this result does not exclude the possibility of a comma-based facil-
Another surprising result in the eyetracking data was the presence of the interference
itation. An important fact is that German readers are trained on using commas, while
effect in the Post-V1 region. If the second NP is forgotten by the time that V1 is processed,
English readers are not, which suggests that commas were of no use for the English
then it should not cause any interference in subsequent regions. There are two possible
participants.
interpretations of this pattern. One is that the second NP is not in fact forgotten, and
the
I will
second
now
is
investigate
that the reappearance
potential explanations
of the interference
for a language-specific
effect is an artefact
forgetting
of processing
effect.
difficulty during earlier processing. We defer discussion of this question until findings in the
remaining experiments are presented.
We turn our attention next to the German experiments.
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