Relative clause extractions generally yield so-called island effects (degraded judgments) across languages (Ross, 1967), (1). However, Swedish and the other Mainland Scandinavian languages comprise famous exceptions to this pattern (Engdahl and Ejerhed, 1982), cf (2):

(1) * Those books I know a girl that writes.

(2) S ̊ana bo ̈cker ka ̈nner jag en tjej som skriver. such books know I a girl who writes

The origin of island effects is under debate. Sprouse et al. (2012) found superadditive effects in judgments of island violations in English – combined effects greater than the sum of the individual costs for extraction and complexity (island structure). Because no correlation was found between participants’ working memory (WM) span (measured via serial recall and n-back) and the superadditive effects, they concluded that island effects must be deri- ved from violations of syntactic constraints rather than processing limitations. In contrast, Hofmeister et al. (2014) did find a correlation between WM span (measured via reading span) and superadditivity in a rapid serial visual presentation experiment. They also found superadditive effects in fully grammatical, but hard to process sentences, suggesting that processing factors do play a role in superadditivity and hence in island effects.

In our talk, we report on the results from an acceptability judgment experiment that was designed to look for superadditive effects in relative clause extractions in Swedish. We investigated the (super)additive effect of clause type (that-clause (3a), (3c), vs. relative clause, (3b), (3d)), and extraction type (short, (3a)–(3b), vs long, (3c)–(3d)). We also tested whether any such effects correlate with WM span, as measured via an n-back and a reading span task. As a control condition, we also included garden-path sentences and their non- garden-path counterparts, as the processing of garden-paths has been shown to correlate with performance on n-back (Novick et al., 2014).(3)

a. Det var Anna som anma ̈lde att en kille snattade s ̊ana chokladkakor it was Anna who reported that a guy stole such chocolate bars i godisaffa ̈ren.from candy store-the

 b.Det var Anna som anma ̈lde en kille som snattade s ̊ana chokladkakor iit was Anna who reported a guy who stole such chocolate bars from godisaffa ̈ren.candy store-the

c. Det var s ̊ana chokladkakor som Anna anma ̈lde att en kille snattade i it was such chocolate bars that Anna reported that a guy stole in godisaffa ̈ren.candy store-the

d.Det var s ̊ana chokladkakor som Anna anma ̈lde en kille som snattade i it was such chocolate bars that Anna reported a guy who stole in godisaffa ̈ren.candy store-the

Unexpectedly, we found superadditive effects for the relative clause extractions, but no cor- relation with WM, and significantly different ratings for garden-path and non-garden-path sentences, but again no relation with WM. However, since there was no relation between the ratings of garden-paths and WM it is evident that the relation between offline acceptability judgements and WM measure is more complex than assumed in the literature. We therefore cannot conclude that the lack of correlation between the superadditive effect and WM for the extraction data is due to syntactic violations. Rather, we conclude that what causes superadditive effects is still an open question that requires further investigation.

Referenser

Engdahl, Elisabet, and Eva Ejerhed, ed. 1982. Readings on unbounded dependencies in Scandinavian languages. Ume ̊a: Ume ̊a University.

Hofmeister, Philip, Laura Staum Casasanto, and Ivan A. Sag. 2014. Processing effects in lin- guistic judgment data: (super-)additivity and reading span scores. Language and Cogni- tion 6:111–145. URL http://journals.cambridge.org/articleS1866980813000070.

Novick, Jared M., Erika Hussey, Susan Teubner-Rhodes, J. Isaiah Harbison, and Michael F. Bunting. 2014. Clearing the garden-path: improving sentence processing through cogni- tive control training. Language, Cognition and Neuroscience 29:186–217.

Ross, John Robert. 1967. Constraints on variables in syntax. Doctoral Dissertation, MIT, Cambridge, Mass. [published as ‘Infinite syntax’. 1986].

Sprouse, Jon, Matt Wagers, and Colin Phillips. 2012. A test of the relation between working- memory capacity and syntactic island effects. Language 88:82–123.