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

Reading time [ms]
400 600 800 1000 1200
Chapter 2 Issues in Relative Clause Processing
SHORT-TERM FORGETTING 24
Experiment 4 (German Eyetracking): grammaticality
grammatical
ungrammatical
V3 V2 V1 Post!V1
Region
Figure 10. 2.7: Mean Effect reading of the times grammaticality and 95% confidence manipulation intervals forinthe the critical German regions eyetracking in the German study
eyetracking by Vasishth study et(experiment al. (2008) 4). (experiment The figure shows 4, p. the 24): effect Mean of grammaticality. reading times and 95% confidence
intervals for the verbs and post-verbal regions.
As in the German SPR study, the matrix verb V1 in the ungrammatical condition
had longer reading time than V1 in the grammatical condition. The reading time at the
2.5.2 word following Explaining V1 showed the no significant Forgetting difference. Effect This result is inconsistent with the VP-
Capacity forgetting hypothesis and consistent with the hypothesis that the middle verb’s prediction is
not forgotten. Not much evidence was found for the NP-forgetting evidence: no interference
Just effectand wasCarpenter seen in the (1992) regions explicitly preceding mention V1, andthe atpossibility V1 the high-interference of forgetting certain condition predictions
showed, surprisingly, in the CC-READER a lower reading model time as compared “Forgetting to by the displacement”. low-interference condition. The underlying
mechanism Havingispresented equal to the pruning experimental hypothesis results, of weGibson turn toand the Thomas interpretation (1999), of the thusfind makingings.
basically the same predictions as the DLT-based approach described above. As has
just been laid out, the VP-forgetting Hypothesis is seemingly not cross-linguistically
valid. Specifically, the hypothesis
General
has been
Discussion
confirmed for English but disconfirmed for
German. We discuss An memory-based the NP- and explanation VP-forgettingcould hypotheses account separately, for the language-specific beginning with the difference
former. inIn two the ways: Englisheither experiments by postulating 1 and 1a awe language-dependent found no evidence consistent capacity with limitthe or a
language-dependent predictions of NP-forgetting, robustness whereas of VP in the predictions. English eyetracking However, study theories (experiment like DLT2) regard and
memory the German processes SPR study as universally (experimentvalid. 3) we Thus, did findconsidering the predicted aneffects. applicability However, ofevidence the DLTbased
inconsistent hypothesis with NP in both forgetting languages was also could found: onlyin mean the German SPRreaders study possess (experiment a higher 3)
memory a shorter capacity reading time thanwas English found inreaders. the Post-V1 However, region there for theshould high-interference be evidence condition, for that
capacity and in the difference eyetracking fromstudy reading (experiment span tasks 4) aand, shorter considering re-reading working time was memory found capacity in the
as
V1
domain-unspecific,
region for the high-interference
there should
condition
also be
(compared
evidence in
to
non-linguistic
the low-interference
working
condition).
memory-
Given these mixed results, it is impossible to make a strong case for NP-forgetting as the
sole explanation for the forgetting effect, particularly since VP forgetting (discussed next)
44