title:	In, On, Over and Between: Toward a functional geometry of spatial prepositions.
author(s):	Simon Garrod
affiliation:
time and place:	Monday, 14.00 - 16.45, room A In the thematic session on Semantics and Cognition
abstract:	Locative expressions are few in number but allow for a wide range of uses (Landau & Jackendoff, 1993). This discrepancy between the small number of apparently simple spatial distinctions being made in language and the frequency and variety of uses to which locative expressions are put presents a challenge for semantic analysis. In particular, it makes it difficult to give a straightforward geometric definition for any of these expressions (Garrod & Sanford,’89; Herskovits, ‘86; Vandeloise, ‘91). The talk describes a series of experiments to show how locatives such as IN, ON, and BETWEEN denote location control relations defined in terms of a functional geometry(Garrod & Sanford, ’89; Garrod, Ferrier and Campbell,’ 99). Such relations capture the way in which objects are seen to control each other’s location by virtue of their spatial arrangement. For example, there is a control relation, which we refer to as fcontainment, by which the ground (i.e., a container) is seen to control the location of the figure (i.e., its content) by virtue of some degree of geometric enclosure. The first series of experiments I will discuss relate to the prepositions IN and ON. They show two things: (1) Confidence in descriptions containing IN and ON relate directly to judgements of the degree to which the ground controls the location of the figure, and, (2) Introducing dynamic information into scenes affects use of descriptions containing IN: Dynamic information consistent with location control of the figure by the ground enhances confidence in IN descriptions for scenes portraying equivalent geometric configurations; By contrast, inconsistent dynamic information reduces confidence in IN descriptions. The other experiment relates to the preposition BETWEEN. Here the control relation is more complicated. If X is BETWEEN Y and Z, then X is seen either to keep Y and Z separate or conversely to hold Y and Z together. This experiment tests the fconnection control relation. Scenes portraying the same geometric configuration of three objects are manipulated to include an alternative connector. Using the rationale behind Garrod et al.s’ (’99) Expt. 2 the prediction is that the presence of an alternative separator should reduce confidence in BETWEEN descriptions. The results supported the prediction for two levels of alternative control analogous to Garrod et al.’ (’99) findings with the preposition ON and alternative sources of support. I will discuss the results of these studies in relation to a functional geometric account for the semantic representation of these locatives. The account has the virtue of offering a simple quasi-geometric definition of the prepositions that can accommodate the wide range of spatial situations to which they can apply. It is also consistent with recent accounts of the perception of complex spatial relations in terms of the so-called “what?” and “where?” systems (Landau & Jackendoff, 1993) and with some accounts of physical imagery (Schwartz, 1999). References: Garrod, S.C. & Sanford, A.J. (1989). Discourse models as interfaces between language and the spatial world. Journal of Semantics, 6, 147-160. Garrod, S., Ferrier, G. & Campbell, S. (1999) In and On: Investigating the functional geometry of spatial prepositions. Cognition, 72, 167-189. Herskovits, A. (1986). Language and Spatial Cognition. Cambridge: Cambridge University Press. Landau, B. & Jackendoff, R. (1993). "What" and "where" in spatial language and cognition. Behavioural and Brain Sciences, 16(2), 217-265. Schwartz, D.L. (1999) Physical imagery: Kinematic versus dynamic models. Cognitive Psychology,38, 433-464. Vandeloise, C. (1991). Spatial Prepositions: A Case Study from French. Translated by Bosch, A.R.K. Chicago/London: The University of Chicago Press.