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

2.5 Forgetting Effects
related tasks. Since there is no such evidence for a language specific memory span, a
pure DLT-based hypothesis cannot account for the non-existence of the forgetting effect
in German. There have to be additional factors that affect the robustness of the VP2
prediction representation.
The most promising explanation is that processing is affected by certain languagespecific
grammatical properties. Vasishth et al. (2008) mention two possibilities how this
could be come about. a) The robustness of the verb representation is directly specified by
the same parameters that shape the grammar and hence the production-based corpus
regularities. b) On the other hand, the more robust representation could be due to
a more effective processing caused by reading skill, which is affected by the mentioned
corpus regularities and not by the parameters directly. The first possibility is matched by
an expectation-based account that directly depends on grammatical properties. Also a
canonicity account would predict SOV structures to be easier in German than in English.
The alternative of reading skill is accounted for by an experience-based approach.
Expectation
A door to language-specific effects could be antilocality. Antilocality has been observed
predominantly in head-final languages like German (Konieczny, 2000) and Hindi (Vasishth
and Lewis, 2006b). The seeming restrictedness of these effects to head-final languages
has lead to the suggestion that the sentence-final verb in these languages is
higher expected than in non-head-final languages. However, a recent study by Jaeger
et al. (2008) shows antilocality effects in English, which is not head-final. The crosslinguistic
explanation is that the expectation for a verb increases with more intervening
material. The longer the distance between the dependent and the expected head the
less likely it becomes that even more adjunctive material will intervene before the head.
Additionally, in most cases the intervening material narrows the possible candidates for
the head, which lowers surprisal even more. The fact that the associated speed-up at the
verb shows slightly different patterns in English and German encourages an expectationbased
account for a language-specific forgetting effect. For example it is imaginable that
in head-final languages the prediction is more precise regarding the exact location of the
verb, whereas in other languages head-finality is too rare to provide exact verb location
statistics in that case.
Experience
The robustness of representations could be shaped by experience. An experience-based
account assumes that the reader adapts processing strategies to often occurring structures.
In result, German readers should be more skilled on head-final structures than
English readers. An explanation based on coarse-grained corpus frequencies would be
equivalent to a canonicity approach. German, being an SOV language exhibits more
head-final structures than English, predicting easier processing. But earlier discussions
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