Agreement attraction in grammatical sentences and the role of the task

This study evaluates two broad classes of language processing accounts that make predictions for sentences like “The admirer of the singer(s) apparently thinks...”. Feature distortion accounts predict increased processing difficulty at the verb in sentences with a plural distractor noun (singers) while similarity-based interference accounts predict the opposite: increased difficulty in sentences with a singular distractor noun (singer). Neither of these effects was reliably observed in earlier research, and the Bayesian meta-analysis of 31 published studies reported here is almost perfectly inconclusive. An explanation may be that both effects occur simultaneously and therefore mask each other. To test this idea, we conducted three single-trial self-paced reading experiments (N1 = 4, 296, N2 = 3, 920, N3 = 3, 559) which orthogonally manipulated agreement attraction and inhibitory interference. Surprisingly, all three experiments produced evidence for agreement attraction but none for inhibitory interference, which supports feature distortion but not similarity-based interference accounts. Experiment 4 (N4 = 3, 535) tested the role of the expected task by preparing participants for a comprehension question (vs. acceptability judgment in Experiments 1–3). It showed neither agreement attraction nor inhibitory interference effects. Our findings demonstratethat agreement attraction effects can arise in grammatical sentences – contra earlier research – but also that these effects crucially depend on the task. This explains inconsistent results in prior research and supports feature distortion as the driving force behind attraction effects in grammatical sentences.