Language as skill: Intertwining comprehension and production

• The “Now-or-Never Bottleneck” link between production and comprehension.
• We outline a computational model, the Chunk-Based Learner (CBL).
• The CBL carries out both production and comprehension.
• The CBL generates behavioral production–comprehension asymmetries.
• This work favors of unitary accounts of production and comprehension.

Are comprehension and production a single, integrated skill, or are they separate processes drawing on a shared abstract knowledge of language? We argue that a fundamental constraint on memory, the Now-or-Never bottleneck, implies that language processing is incremental and that language learning occurs on-line. These properties are difficult to reconcile with the ‘abstract knowledge’ viewpoint, and crucially suggest that language comprehension and production are facets of a unitary skill. This viewpoint is exemplified in the Chunk-Based Learner, a computational acquisition model that processes incrementally and learns on-line. The model both parses and produces language; and implements the idea that language acquisition is nothing more than learning to process. We suggest that the Now-or-Never bottleneck also provides a strong motivation for unified perception–production models in other domains of communication and cognition.