Special passives across the lifespan : cognitive and social mechanisms

Linguists have typically studied constructional change at the aggregate level of speech communities, yet key mechanisms of change (e.g. analogy, automation, schematization) operate within the minds of individual language users. While this is tacitly assumed in the usage-based literature, longitudinal studies investigating to what extent and under which conditions speakers adapt to ongoing change are scarce, especially in the domain of syntax. The present study aims to make headway in this area by addressing three fundamental issues relating to individuality in language change, i.e. how variation and change at the individual level interact with change at the community level (i), how much innovation and change is possible across the adult lifespan (ii) and to what extent related patterns are associated in individual cognition (iii). To gain insight into the cognitive and social mechanisms that drive linguistic change, the present study has selected two interrelated syntactic constructions that undergo significant change in the history of English: the prepositional passive (e.g. he was laughed at) and the Nominativus cum Infinitivo or ‘NCI’ in short (e.g. he is said to be a thief). The expansion of these special passive constructions in Early Modern English presents itself as an interesting case study to explore individual trajectories in language change against the backdrop of temporal language dynamics in the community. The corpus that was established to this purpose contains lifespan data from 50 prolific seventeenth-century authors, who hail from various interconnected communities of practice. As to the first issue specified above (i), the analysis shows that population-level trends often conceal a great deal of variation at the individual level, and may even be in contradiction with individual trajectories. While variation between individuals is in part constrained by social factors, the amount of individuals’ unique residue is not trivial. It is shown that such variation can play a meaningful role in advancing ongoing changes as small shifts in frequency and productivity can increase in magnitude over time, leading to what is eventually recognized as language change. The rate of change may also be accelerated if at least a significant minority of speakers undergoes lifespan change in the direction of the community trend. The study also provides novel insights into the issue of lifespan change in the domain of syntax (ii). While most authors do not appear to be particularly sensitive to ongoing change, some authors do assimilate their usage across the lifespan. Concerning the usage rates of the special passives, fairly extreme lifespan increases are documented, which shows that cognitive routinization may significantly reinforce the use of existing patterns in adulthood and even old age. It is also demonstrated that when a syntactic construction (e.g. the NCI construction) has two different semantic-pragmatic functions, their relative weight may shift significantly across the lifespan. Attested lifespan changes are typically aligned with the community trend, yet speakers may also behave in unpredictably ways, for instance by crystallizing lexically filled patterns at lower levels of the constructional hierarchy which are not the dominant patterns in the community at large. Finally, this study investigates to what extent related patterns such as the special passives are associated in individual cognition (iii). Modeling techniques suggest strong degrees of grammar-internal coherence, with special passives being persistently associated in individual usage. At the aggregate level, however, the association appears to become weaker and in a couple of authors the special passives are found to diverge with age. It is argued that these patterns of dissociation reflect long-term diachronic changes in the usage profiles of the two special passives: the use of the NCI becomes saturated and specializes toward the expression of evidentiality, whereas the prepositional passive continues to recruit new and more complex items. Functionally, these changes are motivated by an inherent disparity in semantic scope; cognitively, they reflect the differential effects of what becomes routinized and entrenched.