On-line Interactions of Context and Grammatical Aspect

On-line Interactions of Context and Grammatical Aspect Sarah E. Anderson (sec57@cornell.edu) a , Teenie Matlock (tmatlock@ucmerced.edu) b , Michael J. Spivey (spivey@ucmerced.edu) b a b Department of Psychology, Cornell University, Uris Hall, Ithaca, NY 14853 USA Cognitive and Information Sciences, University of California, Merced, Merced, CA 95344 USA Abstract What role does grammatical aspect play in the time course of understanding motion events? Although processing differences between past progressive (was walking) and simple past (walked) aspect suggest differences in prominence of certain semantic properties, details about the temporal dynamics of aspect processing have been largely ignored. The current work uses mouse-tracking (Spivey, Grosjean, & Knoblich, 2005) to explore motor output in response to contextual descriptions and aspectual forms. Participants heard descriptions of terrain (difficult or easy) and motion events described with either the past progressive or simple past while placing a character into a scene to match this description. Overall, terrain descriptions modulated responses to past progressive more than to simple past in the region of the screen corresponding to the path. These results, which suggest that perceptual simulation plays a role in the interpretation of grammatical form, provide new insights into the understanding of event descriptions. Keywords: Language Processing; Event Understanding; Mouse-Tracking; Embodied Cognition; Motion Verbs The emerging consensus is that language influences thought (see Boroditsky, 2000; Lucy, 1992; Matlock, Ramscar, & Boroditsky, 2005), but the extent to which this generalizes is uncertain. How does language influence the way people think about everyday events? Can grammar influence the way events are conceptualized, and if so, how? Does hearing just “-ed” versus “-ing” on a motion verb influence listeners’ cognitive processing and motor response, and if so, how? The goal here is to explore the influence of grammatical aspect on the conceptualization of motion events. The main question is how grammar and contextual descriptions differentially influence motor output as people understand language. Many language theorists have observed that grammatical aspect provides temporal information about the internal structure of a verb, specifically providing information about the completion, duration, or repetition of the action (Comrie, 1976; Frawley, 1992). This temporal information, though subtle, can exert a substantial influence on the way a sentence is understood. Take, for example, the following sentences: “David ran to the university,” and “David was running to the university.” Both convey information about an event that occurred in the past, although they use different aspectual forms. The first sentence uses the simple past form of the verb “ran,” emphasizing the completion of the action. In contrast, the second uses the past progressive form, emphasizing the ongoing nature of the action. Despite agreement that aspect provides such temporal “coloring” of a verb’s information, potential processing differences between these aspectual forms have received little attention in psycholinguistic research. More recently, however, aspect was explored in a series of offline studies that examined spatial outcome differences in response to simple past and past progressive verbs (Matlock, Fausey, Cargill, & Spivey, 2007). Participants read a sentence like “This morning David walked to the university” (simple past) or “This morning David was walking to the university” (past progressive), and looked at a schematic drawing that showed a path leading to the destination described in the sentence and ten unevenly spaced identical silhouette characters on the path (e.g., pedestrian with leg extended forward and arms bent as if in motion). Participants were instructed to “circle the man that the sentence is most naturally referring to.” In brief, participants were more likely to circle a character in the middle region of the path with sentences containing past progressive verbs (was walking), and more likely to circle a character in the latter region of the path in response to sentences containing a simple past verb (walked). A similar pattern emerged in a subsequent experiment in which participants were asked to indicate where along the path an object had been dropped after reading simple past or past progressive sentences. These and other results suggest that when participants read simple past sentences, they focus on the end of the path, or the location of the completed action in the scene. In contrast, when participants read past progressive sentences, they focus on the middle section of the path, where the ongoing action would be taking place. These data suggest that different aspectual forms have consequences for thinking about motion events, but questions about the time course of processing remain. On-line processing differences were initially addressed in a series of experiments by Madden and Zwaan (2003), in which the authors demonstrated different aspectual forms produce reaction time differences in narrative reading. Their participants were quicker to respond to pictures showing a completed action after they had read a sentence containing a simple past verb (e.g., The car sped through the intersection) versus a sentence containing a past progressive verb (e.g., The car was speeding through the intersection). However, no such latency differences were found when participants read sentences containing past progressive verbs and saw pictures of intermediate action. The authors suggest that the effect was missing in the past progressive condition because readers represented the ongoing action at different stages of completion. In other words, past progressive verbs could potentially correspond to any of a number of intermediate actions, and this could be un-captured by picture verification