Sequencing of Information Versus Interfacing Between Processing Levels

In his inspiring article, Frawley argues that a distinction should be made between representation and control in cognition. We would like to contribute to the further development of these ideas by penetrating the concept of cognitive computation from a cognitive–neuroscience perspective. Taking this perspective, two varieties of cognitive control can be discerned in what Frawley refers to as ‘unit–level control’ in cognition: One involving the sequencing and coordination of linguistic output, and one constituting interface management across levels of processing. On a first blush, both of these may seem to constitute meta–level control mechanisms in cognition, and both may seem to be conceptually and computationally distinct from object–level processing of linguistic representations, such as phonemes and lexical units. Contrary to this intuitive distinction, interfacing across processing levels in the brain is computationally inseparable from the processing of information “within” processing levels. In contrast, the sequencing and coordination of information, for example, during the production of a linguistic utterance, poses a qualitatively distinct computational problem in the cognitive system. Hence, while the first type of control outlined by Frawley would in a sense correspond to the concept of control in computers, the second type of “control”, referred to heavily in Frawley’s treatment of linguistic impairments, seems indistinguishable from the processing of cognitive “representation”.