Specifying executive representations and processes in number generation tasks

The Interacting Cognitive Subsystems framework, ICS (Barnard, 1985) propose s that central executive phenomena can be accounted for by two autonomous s ubsystems, which process different forms of meaning: propositional and sche matic (implicational) meanings. The apparent supervisory role of the execut ive arises from limitations on the exchange of information between these an d other cognitive subsystems. This general proposal is elaborated in four e xperiments in which a total of 1,293 participants are asked to spontaneousl y generate a large verbal number to varying task constraints, with the inte ntion of specifying the representations of number and task that underlie re sponses. Responses change systematically according to participants' use of explicit propositional information provided by the instructions, and inferr ed implicational information about what the experimenter is requesting. The re was a high error rate (between 6% and 24%), participants producing respo nses that did not fall within the large range indicated by the instructions . The studies support the distinction between propositional and implication al processing in executive function, and provide a framework for understand ing normal executive representations and processes.