Scrambling refers to the phenomenon whereby, in some languages such as Japanese and Korean, constituents in sentences can occur in various different orders that deviate from the canonical one (Ross 1967). For example, in the Korean sentence (1a), the object DP precedes the subject, deviating from the canonical SOV word order. Scrambling may also be cross-clausal in Korean (i.e., long-distance scrambling): in (1b), the embedded object precedes the matrix subject.

Long-distance scrambling also applies to wh-elements in Korean. Since Korean is a wh-in-situ language, wh-elements do not need to move in the formation of wh-questions, as shown in example (2a). Nevertheless, as shown in (2b), wh-elements can also be fronted through long-distance scrambling, resulting in a surface form similar to wh-questions in wh-movement languages. We shall call this operation wh-scrambling.

Long-distance scrambling in Korean has received two main classes of analyses: base-generation analyses, and movement analyses. Under the base-generation analysis, the scrambled elements are merged directly at their surface positions (Kornfilt & Bayer 1994; Neeleman 1994; Bošković & Takahashi 1998; Fanselow 2001: inter alia). For example, under Bošković & Takahashi’s (1998) proposal, the scrambled element (e.g. ‘this book’ in (1b)) is base-generated in its surface TP-adjoined position (and stays there for PF purposes). Since the scrambled element cannot be θ-marked in its surface position, as a last resort, it undergoes an LF lowering operation to receive its θ-role from the embedded V.

Under the movement-based analyses, scrambling involves movement of the scrambled element from its theta-position to its surface position (Ross 1967; Chomsky & Lasnik 1977; Saito 1982; 1985; Hoji 1985; Kuroda 1988; Fukui 1993; Lee 1993; Miyagawa 1997; Bailyn 2001; Ko 2007; 2014: inter alia).

The base-generation accounts, unlike the movement-based accounts, makes room for the possibility that scrambling may not be island sensitive: it is possible that the operations to get a base-generated scrambled DP θ-marked (e.g., LF lowering) may not respect the same locality constraints that restrict overt A’-movements. In fact, in Korean, it has been repeatedly shown that long-distance scrambling can escape various island domains. Ko et al. (2019) tested both leftward and rightward scrambling in Korean experimentally, and showed that both are insensitive to the adjunct and wh-islands; Kim & Ji (2023) showed that Korean scrambling is insensitive to the Complex-NP island; Kim (2026) showed that Korean scrambling shows no adjunct island effect, but a statistically significant yet non-robust relative clause island effect. These findings largely contrast with the island sensitive nature of other A’-movements in Korean such as relativization and topicalization Han 1992; Na & Huck 1993; Han & Kim 2004; Han 2013; Kim 2019; cf. Kim 2013, and some may consider these findings evidence against analyzing scrambling in Korean as a movement operation.

In this paper, we further examine the nature of Korean long-distance scrambling. Specifically, we present a piece of unexpected finding that goes against the previous generalization that Korean scrambling is island insensitive: we find that the scrambling of wh-DPs in Korean is restricted by temporal clausal adjuncts headed by -ttay (when). This contrasts with previous experimental work by Ko et al. (2019) and Kim (2026) that adopt similar factorial designs to probe for island effects, both of which reported no island effect for the scrambling of non-wh DPs out of clausal adjuncts in Korean. Our finding supports the analysis that the long-distance scrambling of wh-elements involves regular upward syntactic movement in Korean (contra Bošković & Takahashi’s 1998 analysis for Japanese); it also points to the possibility that wh-scrambling and the scrambling of non-wh DPs may be derived via different mechanisms, given the different findings in the current study and Ko et al. (2019) and Kim (2026): non-wh-scrambling may be derived via base-generation of the seemingly displaced elements in the left periphery, whereas this base-generation option is not available for wh-elements.

In this paper, we present results from three experiments. Experiment 1 presents evidence for the adjunct island effect on wh-scrambling in Korean. Experiment 2 shows that the clausal adjuncts tested in Experiment 1 are interpreted as discourse backgrounded. Experiment 3 shows that adjunct islands do not restrict in-situ wh-DPs, in line with previous generalizations that in-situ wh-DPs are not restricted by island effects in Korean (Kim & Goodall 2016; Kim et al. 2023, cf. Cho 2018) and crosslinguistically (Huang 1982; Tsai 1994; 2009; Sprouse et al. 2011; Çakır 2016; 2017; Tian et al. 2022; Jin & Yan 2025, cf. Lu et al. 2020; Chieu 2022; Kim et al. 2023; Chen 2024; Yue & Xiang 2025; Tanaka 2025). Taken together, Experiments 2 and 3 confirm that the results of Experiment 1 reflect a genuine syntactic island effect on movement, as opposed to a discourse-level ban on new-information-seeking questions targeting discourse-backgrounded information (Abeillé et al. 2020; Goldberg 2013; Namboodiripad et al. 2022; Cuneo & Goldberg 2022; 2023; Lu et al. 2025; Ambridge & Goldberg 2008).

Under certain discourse-level accounts of island effects (e.g., Erteschik-Shir 1973; Ambridge & Goldberg 2008; Goldberg 2013; Namboodiripad et al. 2022; Cuneo & Goldberg 2022; 2023; Lu et al. 2025), island effects (including the temporal adjunct island effect observed in Experiment 1) could reflect a discourse constraint on question formation that is orthogonal to whether syntactic movement is involved: discourse backgrounded/presupposed content cannot be questioned. Under these accounts, the existence of island effects cannot be taken as evidence for the existence of syntactic movement. Experiments 2 and 3 combined test whether this is a plausible explanation for the island effect observed in Experiment 1. Experiment 2 tests whether the temporal adjuncts used in Experiment 1 are indeed discourse backgrounded, as expected under a discourse account of island effect. Experiment 3 tests whether the temporal adjunct clauses restrict in-situ wh-questions where there is no overt syntactic movement. If Experiment 2 shows that the temporal adjunct clauses are interpreted as discourse backgrounded, but Experiment 3 shows that the temporal adjunct clauses do not restrict wh-in-situ, the results from the two experiments taken together would challenge the discourse account as an explanation for the island effect observed in Experiment 1 (alternative to an explanation where wh-scrambling involves genuine syntactic movement restricted by islands).

In Experiment 2, we have shown that the -ttay temporal adjunct clauses in Korean, just like their English counterparts, are interpreted to be discourse backgrounded. In this experiment, we test whether in-situ wh-DPs are sensitive to the -ttay temporal adjunct island in Korean. If the adjunct island effect observed in Experiment 1 reflects a discourse constraint on wh-questions regardless of whether movement is involved, we expect the same island effect to show up for wh-in-situ sentences, given the discourse backgrounded status of adjuncts. If the island effect in Experiment 1 reflects a locality constraint on movement, we do not expect in-situ wh-DPs to show the same effect.

This squib makes three main contributions to the study of scrambling and island effects in Korean.

First, on the empirical side, we present experimental evidence suggesting that wh-scrambling is sensitive to the -ttay temporal adjunct island in Korean. This contrasts with earlier work demonstrating adjunct island insensitivity for the long-distance scrambling of non-wh DPs (Ko et al. 2019; Kim 2026), as well as with Kim & Goodall’s 2016 and our findings in Experiment 3 that in-situ wh-DPs are also insensitive to the adjunct island. Our finding thus expands the empirical landscape of long-distance scrambling and the adjunct island effect in Korean. Admittedly, we only examined one particular type of clausal adjunct (-ttay clauses), and it is possible that movements may display different sensitivity to different types of clausal adjuncts, as have been demonstrated crosslinguistically (Truswell 2007; Bondevik et al. 2021; Bondevik & Lohndal 2023). We leave it to future studies to further expand the empirical coverage by testing other types of adjunct clauses.

Second, our findings point to the theoretical possibility that wh-scrambling, but not regular scrambling, may be derived through syntactic movement. If wh-scrambling necessarily proceeds via overt A′-movement, the adjunct island effect follows naturally. Meanwhile, the island insensitivity of non-wh scrambling remains consistent with base-generation accounts of scrambling (e.g. Bošković & Takahashi 1998; Fanselow 2001) in which scrambled DPs have the option to be directly merged at their surface positions. An open question, however, is what bars wh-elements from being base-generated at its surface scrambled position. We do not intend to offer a solution in this squib, and will leave this as an important question for future work.

Apart from the aforementioned explanation based on the different derivation paths for wh- and non-wh-scrambling, there are a few alternative explanations for why our findings diverge from previous experiments on non-wh-scrambling in Korean. In Ko et al. (2019), the authors gave two speculative explanations for why they didn’t find island effects on non-wh-scrambling. First, the authors speculate that Korean allows multiple specifiers, and the scrambled phrases in Korean can escape islands by merging as multiple specifiers of C. This explanation is implausible: the availability of multiple specifier positions might account for the lack of wh-island effects in Korean (which is also reported in Ko et al. 2019), but not clausal adjunct island effects, which cannot be straightforwardly attributed to the lack of a CP specifier position at the island edge. A second explanation provided in Ko et al. (2019) is that their experiment might be confounded by a floor effect, which masks an island effect by compressing the acceptability contrasts near the bottom of the scale. However, Kim (2026) replicates Ko et al.’s 2019 lack of adjunct island effect, and the average acceptability Z-scores for all conditions in Kim (2026) are positive and thus not confounded by any floor effect. Finally, a third possible explanation is that the short dependency length conditions in our Experiment 1 are different from the short conditions in Ko et al. (2019), which might have led to different experimental results. Our stimuli involve subject wh-elements in the short conditions and object wh-elements in the long condition, whereas Ko et al.’s stimuli involve object wh-elements in all conditions. Ko et al. observed a pronounced acceptability contrast between their short.island and short.non-island conditions, and this contrast drives a statistically significant sub-additive interaction effect between length and structure, in the opposite direction of an island effect. However, in our Experiment 1, we did not observe any pronounced contrast between the short conditions. One might speculate that the difference in findings of the two studies is driven by the difference in the short conditions. An anonymous reviewer suggests that the contrast between the two studies might reflect a subject-object asymmetry in scrambling in Korean. However, any such asymmetry should be reflected as a main effect in dependency length in Experiment 1, and should not affect the super-additive island effect. Alternatively, there could be a penalty that selectively affects object scrambling from the matrix when an adjunct clause is present. Since both short conditions in Ko et al. (2019) involve the extraction of the indirect object DP from a position that linearly follows the embedded (complement or adjunct) clause, the finding in Ko et al. (2019) could reflect a processing-level penalty that burdens the processing of dependencies linearly spanning adjunct clauses but not ones that linearly span complement clauses.4 Nevertheless, one should note that Kim (2026) used stimuli similar to the ones in Ko et al. (2019) where all scrambled elements are objects, but there is no contrast between the two short conditions in Kim (2026). We leave it to future studies to test whether this contrast in the short conditions reported in Ko et al. (2019) is a reliably replicable effect.

A third contribution of this study is that the results of Experiments 2 and 3 inform the broader debates about the status of discourse-based accounts of island effects. Experiment 2 confirmed that the -ttay adjuncts in Korean are indeed interpreted as discourse backgrounded, just like their English counterparts. However, Experiment 3 showed that wh-in-situ questions can target elements inside these -ttay clauses without any island effect. This means that the degradation observed in Experiment 1 cannot be reduced to a pragmatic clash between the new-information-seeking nature of wh-questions and the backgrounded status of clausal adjuncts. On a higher level, given the dissociation between discourse backgroundedness and islandhood we observed, the findings of Experiments 2 and 3 constitute a counter-example to the discourse-based accounts that attribute island effects to the clash between the discourse foregrounding/new-information-seeking function of wh-questions, and the discourse backgrounded status of certain structural domains (Ambridge & Goldberg 2008; Goldberg 2013; Cuneo & Goldberg 2022; Namboodiripad et al. 2022). Nevertheless, this does not mean that all discourse-based accounts of islands are untenable. One recent proposal by Winckel et al. (2025) states that only wh-elements that undergo movement are foregrounded. Our findings are still compatible with this particular account: the island effect in Exp.1 arises because the wh-scrambling construction involves movement of the wh-element, whereas the in-situ argument wh-questions in Exp.3 do not involve (overt or covert) movement and thus do not give rise to any discourse clash. Note that under this account, we can still conclude that wh-scrambling in Korean involves movement: if the sentence-initial wh-elements are base-generated, Winckel et al.’s (2025) account would predict no island effect since no movement is involved, contrary to our finding.

In sum, this squib presents a data point that wh-scrambling, unlike non-wh-scrambling or wh-in-situ, is sensitive to the adjunct island constraint in Korean. This result is compatible with a movement-based analysis of wh-scrambling, and invites a reevaluation of the assumption that Korean scrambling constitutes a single unified operation.