Edinburgh Research Explorer Toward a mechanistic psychology of dialogue Citation for published version: Pickering, MJ & Garrod, S 2004, 'Toward a mechanistic psychology of dialogue', Behavioral and Brain Sciences, vol. 27, no. 02, pp. 169-225. https://doi.org/10.1017/S0140525X04000056 Digital Object Identifier (DOI): 10.1017/S0140525X04000056 Link: Link to publication record in Edinburgh Research Explorer Document Version: Publisher's PDF, also known as Version of record Published In: Behavioral and Brain Sciences Publisher Rights Statement: ©Pickering, M. J., & Garrod, S. (2004). Toward a mechanistic psychology of dialogue. Behavioral and Brain Sciences, 27(02), 169-225doi: 10.1017/S0140525X04000056 General rights Copyright for the publications made accessible via the Edinburgh Research Explorer is retained by the author(s) and / or other copyright owners and it is a condition of accessing these publications that users recognise and abide by the legal requirements associated with these rights. Take down policy The University of Edinburgh has made every reasonable effort to ensure that Edinburgh Research Explorer content complies with UK legislation. If you believe that the public display of this file breaches copyright please contact [email protected] providing details, and we will remove access to the work immediately and investigate your claim. Download date: 28. Sep. 2021 BEHAVIORAL AND BRAIN SCIENCES (2004) 27, 169–226 Printed in the United States of America Toward a mechanistic psychology of dialogue Martin J. Pickering Department of Psychology, University of Edinburgh, Edinburgh EH8 9JZ, United Kingdom [email protected] http://www.psy.ed.ac.uk/Staff/academics.html#PickeringMartin Simon Garrod Department of Psychology, University of Glasgow, Glasgow G12 8QT, United Kingdom [email protected] http://staff.psy.gla.ac.uk/~simon/ Abstract: Traditional mechanistic accounts of language processing derive almost entirely from the study of monologue. Yet, the most natural and basic form of language use is dialogue. As a result, these accounts may only offer limited theories of the mechanisms that un- derlie language processing in general. We propose a mechanistic account of dialogue, the interactive alignment account, and use it to de- rive a number of predictions about basic language processes. The account assumes that, in dialogue, the linguistic representations em- ployed by the interlocutors become aligned at many levels, as a result of a largely automatic process. This process greatly simplifies production and comprehension in dialogue. After considering the evidence for the interactive alignment model, we concentrate on three aspects of processing that follow from it. It makes use of a simple interactive inference mechanism, enables the development of local di- alogue routines that greatly simplify language processing, and explains the origins of self-monitoring in production. We consider the need for a grammatical framework that is designed to deal with language in dialogue rather than monologue, and discuss a range of implica- tions of the account. Keywords: common ground; dialogue; dialogue routines; language comprehension; language production; monitoring; perception-be- havior link 1. Introduction gree of experimental control necessary. Studies of language comprehension are fairly straightforward in the experi- Psycholinguistics aims to describe the psychological pro- mental psychology tradition – words or sentences are stim- cesses underlying language use. The most natural and ba- uli that can be appropriately controlled in terms of their sic form of language use is dialogue: Every language user, characteristics (e.g., frequency) and presentation condi- including young children and illiterate adults, can hold a tions (e.g., randomized order). Until quite recently it was conversation, whereas reading, writing, preparing speeches also assumed that imposing that level of control in many and even listening to speeches are far from universal skills. language production studies was impossible. Thus, Bock Therefore, a central goal of psycholinguistics should be to (1996) points to the problem of “exuberant responsing” – provide an account of the basic processing mechanisms that how can the experimenter stop subjects from saying what- are employed during natural dialogue. ever they want? However, it is now regarded as perfectly Currently, there is no such account. Existing mechanis- possible to control presentation so that people produce the tic accounts are concerned with the comprehension and appropriate responses on a high proportion of trials, even production of isolated words or sentences, or with the pro- in sentence production (e.g., Bock 1986a; Levelt & Maas- cessing of texts in situations where no interaction is possi- sen 1981). ble, such as in reading. In other words, they rely almost en- Contrary to many people’s intuitions, the same experi- tirely on monologue. Hence, theories of basic mechanisms mental control is possible with dialogue. For example, depend on the study of a derivative form of language pro- Branigan et al. (2000) showed effects of the priming of syn- cessing. We argue that such theories are limited and inad- tactic structure during language production in dialogue that equate accounts of the general mechanisms that underlie were exactly comparable to the priming shown in isolated processing. In contrast, this paper outlines a mechanistic sentence production (Bock 1986b) or sentence recall (Pot- theory of language processing that is based on dialogue, but ter & Lombardi 1998). In Branigan et al.’s study, the degree that applies to monologue as a special case. of control of independent and dependent variables was no Why has traditional psycholinguistics ignored dialogue? different from that in Bock’s study, even though the exper- There are probably two main reasons, one practical and one iment involved two participants engaged in a dialogue theoretical. The practical reason is that it is generally as- rather than one participant producing sentences in isola- sumed to be too hard or impossible to study, given the de- tion. Similar control is exercised in studies by Clark and col- © 2004 Cambridge University Press 0140-525X/04 $12.50 169 Pickering and Garrod: Toward a mechanistic psychology of dialogue leagues (e.g., Brennan & Clark 1996; Wilkes-Gibbs & Clark is Clark. However, his primary focus is on the nature of the 1992; also Brennan & Schober 2001; Horton & Keysar strategies employed by the interlocutors rather than basic 1996). Well-controlled studies of language production in di- processing mechanisms. Clark (1996) contrasts the “lan- alogue may require some ingenuity, but such experimental guage-as-product” and “language-as-action” traditions. The ingenuity has always been a strength of psychology. language-as-product tradition is derived from the integra- The theoretical reason why psycholinguistics has ignored tion of information-processing psychology with generative dialogue is that psycholinguistics has derived most of its grammar and focuses on mechanistic accounts of how peo- predictions from generative linguistics, and generative lin- ple compute different levels of representation. This tradi- guistics has developed theories of isolated, decontextual- tion has typically employed experimental paradigms and ized sentences that are used in texts or speeches, that is, in decontextualized language; in our terms, monologue. In monologue. In contrast, dialogue is inherently interactive contrast, the language-as-action tradition emphasizes that and contextualized: Each interlocutor both speaks and utterances are interpreted with respect to a particular con- comprehends during the course of the interaction; each in- text and takes into account the goals and intentions of the terrupts both others and himself; on occasion two or more participants. This tradition has typically considered pro- speakers collaborate in producing the same sentence cessing in dialogue using apparently natural tasks (e.g., (Coates 1990). So it is not surprising that generative lin- Clark 1992; Fussell & Krauss 1992). Whereas psycholin- guists commonly view dialogue as being of marginal gram- guistic accounts in the language-as-product tradition are maticality, contaminated by theoretically uninteresting admirably well-specified, they are almost entirely decon- complexities. Dialogue sits ill with the competence/perfor- textualized and, quite possibly, ecologically invalid. On the mance distinction assumed by most generative linguistics other hand, accounts in the language-as-action tradition (Chomsky 1965), because it is hard to determine whether a rarely make contact with the basic processes of production particular utterance is “well-formed” or not (or even or comprehension, but rather present analyses of psy- whether that notion is relevant to dialogue). Thus, linguis- cholinguistic processes purely in terms of their goals (e.g., tics has tended to concentrate on developing generative the formulation and use of common ground; Clark 1985; grammars and related theories for isolated sentences; and 1996; Clark & Marshall 1981). psycholinguistics has tended to develop processing theories This dichotomy is a reasonable historical characteriza- that draw upon the rules and representations assumed by tion. Almost all mechanistic theories happen to be theories generative linguistics. So far as most psycholinguists have of the processing of monologue; and theories of dialogue thought about dialogue, they have