Working Memory and Relative Clause Attachment under Increased Sentence Complexity Akira Omaki Department of Second Language Studies, University of Hawai‘i at Mānoa 1. Introduction 3. Experiment 1 Method Relative Clause Attachment Local Attachment (1) Someone shot… …the servant of the actress [who was on the balcony]. (N1) (N2) (RC) Results Figure 1. M ean NLA responses & RST scores in Experiment 1 Participants: 36 English native speakers Materials: 32 target items (4) + 75 fillers Mean NLA: SC (4a) Embedded Condition (EC) burned herself the other day adored]] was very nice. Local Attachment (LA) English, Arabic, Norwegian, Romanian, Croatian, etc. Non-local Attachment (NLA) Spanish, Dutch, Afrikaans, French, Greek, Russian etc. Various Accounts for the cross-linguistic differences: • Implicit Prosody (Fodor, 2002) • Construal Theory (Frazier & Clifton, 1996) • Tuning Hypothesis (Mitchell et al., 1995) • Attachment Binding (Hemforth et al., 1998) The babysitter said [that the sister of the schoolgirl who burned herself the other day was very nice.] Mendelsohn & Pearlmutter (1999): English object-modifying RC + Reading Span Test Swets, Desmet, Hambrick & Ferreira (2004): Subject modifying RC in English (LA preference) and Dutch (NLA preference) + Reading Span Test 20% 0% 20.00 Example Question: Who got burned the other day? 1. the sister 2. the schoolgirl 30.00 40.00 50.00 60.00 70.00 RST scores • Significant negative correlation btw. RST scores and NLA responses 2-tailed correlation in… EC condition: r = - .482 (p<.001) SC condition: r = - .561 (p<.001) The greater RS leads to an LA preference. (Replicates previous findings) 1. Read the whole sentence on a computer screen 2. then press the space bar to show the question Offline experiments by… 40% Less complex (Storage cost at “who” = 2) A. Offline reading experiment on computer Individual differences in RC attachment preferences? Working Memory Capacity 60% (4b) Sentence-complement Condition (SC) Procedure HOWEVER… Trend line (SC) 80% [The babysitter [that the sister of the schoolgirl who Cross-linguistic differences in RC attachment preferences: Trend line (EC) 100% More complex (Storage cost at “who” = 4) Non-local Attachment Mean NLA: EC • No significant difference between EC & SC condition (Correlation between EC and SC condition was over .90) B. Reading Span Test: A version of Waters & Caplan’s (1996) • Acceptability judgment + Recall Task • Score 1 was added when both judgment and recall were correct (Max score: 70) • Weak trend for a local attachment preference Mean NLA responses in… EC condition: 42.19% (SD=27.60) SC condition: 46.35% (SD=28.48) Question: Why the lack of sentence complexity effect? A. Problems with the methodology? They may not have read the whole sentence, since one can answer the question by just looking at the relevant RC attachment region Addressed in Experiment 2, word-by-word self-paced reading task Their Findings: The greater WM capacity leads to an LA preference (i.e., Low-spans prefer NLA, High-spans prefer LA) 4. Experiment 2 (in progress) Method Very surprising, in that various locality principles are supposed to minimize processing burden (e.g., Late Closure (Frazier, 1987), Recency (Gibson et al., 1996)) 2. Goal of the Present Study Preliminary RT Results Main effect of complexity (F1&F2) in ‘of’ ‘schoolgirl’ ‘who’ burned’ Reflects the storage cost (Gibson, 2000) Participants: 32 English native speakers Materials: 32 target items (5) + 73 fillers Procedure: Self-paced reading + RST from Exp 1 (5a, c) Complex/Non-complex, forced LA The babysitter (said) that the brother of the schoolgirl who burned herself the other day adored was very nice. (5b, d) Complex/Non-complex, forced NLA The babysitter (said) that the brother of the schoolgirl who burned himself the other day was very nice. To further examine whether WM capacity interacts with the RC attachment ambiguity in off-line processing (Exp 1 ) and on-line processing (Exp 2) by investigating… Main effect of complexity in ‘was’ (F1&F2) Reflects the integration cost (Gibson, 2000) Main effect of attachment (though only F1) in ‘himself/herself’ LA attachment preference, regardless of the sentence complexity No main effect of interaction in any of the regions (F1&F2) Figure 2. Overall Reaction Times by region in Experiment 2 (a) whether high-spans and low-spans differ in RC attachment preferences (as in previous studies), and Complex/LA Complex/NLA Non-complex/LA Non-Complex/NLA Storage cost 1600 (b) whether the sentence complexity (i.e., the amount of memory cost) interacts with RC attachment preferences (cf. Eastwick & Phillips, 1999) 1400 1200 LA preference Integration cost 1000 800 600 High vs. Low: Between-subjects 400 The babysitter (said) • Mean RST score (n = 32): 45.9, thus 46 as cut-off 16 low-spans, 16 high-spans Complexity (2) x attachment (2) x span size (2) design 1150 900 650 the brother 1. High-spans generally slower 2. Integration, but NOT attachment, interacts with span size Regions with main effect of span size: ‘himself/herself’ and ‘was’ Figure 3: Span size effect in Mean RTs at 'himself/herself' that Figure 4: Span size effect in Mean RTs at 'was' 1200 Main Effect: RST p<.05, Attach p=.053 No interaction 1023.68 925.18 906.74 1000 802.29 634.41 800 600 537.24 552.35 541.71 Main Effect: RST p<.01, Complex p<.0005 Complx*RST p<.05 955.48 860.26 584.48 580.20 503.06 467.73 445.38 Low Span Complex/LA Complex/NLA High Span Non-Complex/LA Non-Complex/NLA the schoolgirl who burned himself/ herself the other day adored was 5. Summary • The general LA preference was observed in offline and online processing • RS significantly correlated with RC attachment ONLY in offline processing. In Exp 2, RS significantly interacted with integration cost, but not with attachment (cf. Caplan & Waters, 1999) – this suggests that (at least) initial RC attachment preference is not influenced at all by memory capacity. 402.19 6. Acknowledgement 400 400 of 200 Low Span Complex/LA Complex/NLA High Span Non-Complex/LA Non-Complex/NLA • I thank Matt Prior, Amy J. Schafer, Barbara Schulz, and Bonnie D. Schwartz for their help at various stages. I also thank the snack-eaters at the Psycholinguistics 3ji-no Oyatsu meetings. • This research was partially supported by Elizabeth Holmes-Carr Scholarship, received with much appreciation.