Conjunction meaning can modulate parallelism facilitation: Eye-tracking evidence from German clausal coordination

•When the second conjunct parallels (vs. doesn’t) the first, it is read faster.•Such facilitation through structural parallelism could be due to simple priming.•But conjunction meaning and context modulated constituent order parallelism effects.•More than simple priming is necessary to account for these parallelism effects.

In and-coordinated clauses, the second conjunct elicits faster reading times when it parallels (vs. does not parallel) the first in constituent order. This paper examined whether such parallelism facilitation results from simple constituent order priming from the first to the second clause, or whether it can be modulated through the linguistic context (the conjunction and clausal relations). Three eye-tracking experiments on German assessed this issue by manipulating conjunction meaning and type within subjects (resemblance: ‘and’ vs. adversative: ‘but’ or ‘while’; coordinating: ‘and’ and ‘but’; subordinating: ‘while’), and by varying the clausal relations between experiments. Clausal parallelism facilitation was reduced when syntactic dependence of the clauses from a superordinate verb reinforced their coherence, and semantic expectations for ‘but’ and ‘while’ were violated through the parallel constituent order and thematic role relations of noun phrases. By contrast, it was not reduced when the same expectations were satisfied through other sentence constituents (temporally contrastive adverbs) and when the coordination involved matrix clauses. The contextual modulation of parallelism facilitation rules out simple priming as the only underlying mechanism. The observed facilitation rather reflects compositional processing of the coordinands and the conjunction in the linguistic context.