Introduction Language comprehension involves: Coherence Cohesion

1. Examining Anaphor Resolution Using Event-Related PotentialsTali Ditman1, Phillip J. Holcomb1, & Gina R. Kuperberg2Tufts University, Medford, MA1; Massachusetts General Hospital, Charlestown, MA2 • Introduction • Language comprehension involves: • Coherence • Cohesion • Anaphors are words that refer back to previously presented words, or antecedents • How do people use context to link anaphor with its correct antecedent? • Gernsbacher (1989): • Enhancement of correct antecedent • Active suppression of incorrect antecedent • Predictions: • Correct antecedent easier to integrate into preceding context (smaller N400 to correct antecedent) • More difficult sentence wrap-up with incorrect antecedent (larger N400 at final word) Figure 3 – Responses to Probe: Are participants resolving anaphor? Yes! Figure 6– Final word: The ring wasattractive. -- Correct -- Control -- Incorrect FPz FP2 FP1 F7 F3 Fz F4 F8 FC1 FC2 FC6 FC5 Cz T4 T3 C3 C4 CP5 CP2 CP1 CP6 Pz T5 P3 P4 T6 Oz O1 O2 CP2 • Method • 16 right-handed native English speaking participants (9 female, 21.25 years) • ERPs measured at 32 sites (see Figure 1) • 126 scenarios (see Figure 2 for example) • First 3 sentences self-paced and presented potential antecedents (e.g., ring, bracelet, nightgown), two of which were lexically related to the anaphor • Fourth sentence presented word-by-word and ended with the anaphor • Fifth sentence presented word-by-word and always started with the correct (lexically appropriate, context appropriate), incorrect (lexically appropriate, context inappropriate), or control (lexically inappropriate, context inappropriate) antecedent • Participants were asked to decide whether probe word was referred to by the anaphor P< .05 Figure 7– Response to Probe – 1st half vs 2nd half Figure 4 – RT to Probe No ERP differences at final word but could this be due to the strategy use over the course of the experiment?

2. FP1 FP1 FPz FPz FP2 FP2 FP1 FPz FP2 F4 F4 F8 F7 Fz F3 F7 F4 Fz F8 F3 FC6 FC1 FC2 FC5 C4 T4 C3 Cz T3 FC6 FC5 FC1 FC2 CP2 CP6 CP1 CP5 T3 C3 Cz T4 C4 P3 P4 T5 Pz T6 CP1 CP5 CP2 CP6 Oz O2 O1 T5 P3 Pz P4 T6 FP2 FP1 FPz Oz O1 O2 Figure 2–Scenario F7 F3 F4 Fz F8 FC1 FC2 FC6 FC5 A ring is worn on a finger. A bracelet is worn on a wrist. A nightgown is worn to sleep. Lisa’s finger sparkled with the jewelry. The ring was attractive. The bracelet was attractive. The nightgown was attractive. PROBE: RING T3 C4 C3 Cz T4 ANAPHOR CP1 CP5 CP2 CP6 T5 P3 Pz P4 T6 O1 Oz O2 Figure 8– Final word – 1st Half of Experiment Figure 1 – Electrode Montage Figure 5– Resolution word:The ringwas attractive. Fz A left anterior negativity (LAN), thought to reflect working memory load (King & Kutas, 1995), was found in sentences with incorrect antecedents only in the second half, during which performance on the incorrect probe was significantly improved from the first half. Figure 9– Final word – 2nd Half of Experiment -- Correct -- Control -- Incorrect Fz CP2 The smallest N400 was elicited by the correct antecedent and the largest N400 was elicited by the control. References Gernsbacher (1989). Mechanisms that improve referential access. Cognition, 32(2), 99-156. King, J. W., & Kutas, M. (1995). Who did what and when? Using word- and clause-level ERPs to monitor working memory usage during reading. Journal of Cognitive Neuroscience, 7, 376-395. • Discussion • Immediately following anaphor resolution, a correct antecedent is more easily integrated into its preceding context. • After anaphor resolution, processing an incorrect antecedent may involve an increased working memory load. • Future directions will further examine the effect of working memory and strategy use on anaphor resolution, as well as the time course of this effect. Phillip J. Holcomb was supported by NICHD (HD25889 and HD043251). Gina R. Kuperberg was supported by NIMH (K23 MH02034), NARSAD (with the Sidney Baer Trust), and by the Institute for Mental Illness and Neuroscience Discovery (MIND).