1. DETECTING VIOLATIONS IN REAL- AND COUNTERFACTUAL- WORLD CONTEXTS: EYE-MOVEMENTS AND ERP ANALYSIS BACKGROUND Counterfactual reasoning is valid reasoning arising from premises that are true in a hypothetical model, but false in actuality. Investigations of counterfactuals have concentrated on reasoning and production (Fauconnier, 1994; Walsh & Byrne, 2004) and psycholinguistic research has been more limited (Urrutia & de Vega, 2005). EXPERIMENT 4 [1] & [2] CW- consistent/ inconsistent If margarine contained a detergent it would have many domestic uses. Mum could use margarine in her hair/ baking and impress her friends and family. [3] & [4] RW- inconsistent/ consistent If Mum wanted to impress friends and relatives she would have lots of work to do. Mum could use margarine in her hair/ baking and impress her friends and family. - 160 experimental items displayed in a fixed random order alongside filler items - 19 (20 – 1) native English speakers - Within-subjects 2 (CW/ RW) x 2 (consistent/ inconsistent) design - EEG continuously recorded from 72 scalp electrodes and averaged time- locked to onset of consistent/ inconsistent critical word - N400 effect (largest in parietal areas): - RW & CW inconsistent more negative than consistent - RW inconsistent effect begins earlier than CW inconsistent - RW more negative than CW Topographic maps of ERP difference waveforms: Left panel: ERP difference (inconsistent minus consistent) for time range 350- 500ms after critical noun onset Right panel: ERP difference (RW minus CW) for time range 350-500ms after critical noun onset Heather J Ferguson, Anthony J Sanford and Hartmut Leuthold Department of Psychology, University of Glasgow EXPERIMENT 1 [1] CW- consistent If cats were vegetarians they would be cheaper for owners to look after. Families could feed their cat a bowl of |carrots and| it would gobble it down happily. [2] RW- inconsistent If cats are hungry they usually pester their owners until they get fed. Families could feed their cat a bowl of |carrots and| it would gobble it down happily. [3] RW- consistent If cats are hungry they usually pester their owners until they get fed. Families could feed their cat a bowl of |fish and| it would gobble it down happily. - 24 experimental items displayed in a fixed random order alongside filler items - 36 native English speakers - SRI Dual Purkinje Generation 5.5 eye-tracker - Within-subjects 3-factor design - RW violations were treated as acceptable in a pre-specified CW context - Effect on early processing for RW violations regardless of prior context REFERENCES Fauconnier, G. (1994). Mental spaces: Aspects of meaning construction in natural language. Cambridge University Press. Urrutia, M.A., & de Vega, M. (2005). Canceling updating in counterfactuals. Paper presented at Society for Text & Discourse 15th Annual Meeting, Vrije Universiteit Amsterdam. Walsh, C.R., & Byrne, R.M.J. (2004). Counterfactual Thinking and the Temporal Order Effect. Memory and Cognition, 32, 369-378. GLASGOW LANGUAGE PROCESSING CONCLUSIONS - Eye- movement data suggests an initial processing strategy using RW knowledge - But, prior context is rapidly used so that world inconsistent information leads to anomaly detection behaviour (N400 effect- largest in parietal areas) - Both eye-movements and ERPs suggest RW inconsistencies are more ‘powerful’ and are detected faster than CW inconsistencies - Comprehending RW uses mainly parietal areas, but CW employs more global activation EXPERIMENT 2 [4] CW- inconsistent If cats were vegetarians they would be cheaper for owners to look after. Families could feed their cat a bowl of |fish and| it would gobble it down happily. - 36 experimental items displayed in a fixed random order alongside filler items - 36 native English speakers - Within-subjects 2 (CW/ RW) x 2 (consistent/ inconsistent) design - RW congruent items were processed as anomalous in a CW context - RW inconsistencies led to longer reading times, more fixations and more regressions around the critical region than CW inconsistencies EXPERIMENT 3 [5] & [6] RW- inconsistent & RW- consistent Evolution dictates that cats are carnivores and cows are vegetarians. CONCLUSIONS - Initial processing of a word is in terms of real world knowledge even in CW contexts. RW inconsistencies are detected faster than CW inconsistencies, as the effects for a RW inconsistency are detected in the first-pass RT measures. - Both ‘world inconsistent’ conditions lead to longer reading times, more fixations and more regressions around the critical noun than ‘world consistent’ conditions. Thus prior context is rapidly utilised.