Processability theory

Processability theory is a theory of second language acquisition developed by Manfred Pienemann. (Pienemann 1998) The theory has been used as a framework by scientists from Europe, North America, Asia and Australia.

Processability theory (PT) is a cognitive approach to second language acquisition that seeks to explain developmental schedules as well as learner variation. It is based on Levelt’s (1989) approach to language generation and is formally operationalized using Lexical-Functional Grammar (Bresnan 2001). PT’s core assumption is that learners can produce only what they can process. PT is therefore based on the architecture of human language generation that is constructed hierarchically. It is argued that learners are constrained to follow that hierarchical order of processability in acquiring any target language. In other words, the hierarchy of processability is the core of the predictive machinery entailed in PT. Of course, the hierarchy must be applied to the specific conditions of any target language. This is done using LFG formalisms. When applied to ESL, this results in an array of predictions for developmental schedules in syntax and morphology. For instance, word order is predicted to be initially constrained to canonical word order even in questions, as Do-support and auxiliary inversion would require processing resources that are not initially available.

PT also includes theoretical modules dealing with L1 transfer, inter-learner variation and the role of linguistic typology. It comes with detailed methodological tools. PT has been applied to second language classrooms and to linguistic profiling.