Task unrelated thought refers to thought directed away from the current situation; for example, a day dream. Encapsulated models of cognition propose that qualitative changes in consciousness, i.e., the production of TUT, can be explained in terms of changes in the quantity of resources deployed for task completion. In contrast, distributed models of cognition emphasize the importance of holistic processes in the generation and maintenance of task focus and are consistent with the effects of higher order variables such as schemata. (...) Three experiments were conducted on healthy participants using a categorical stimulus organization to contrast distributed and encapsulated views of cognition. Experiments 1 and 2 showed that despite the increased difficulty of the alphabetical verbal fluency task fewer TUTs were produced during category fluency condition. Experiment 3 replicated the categorical suppression of TUT while encoding and recalling information in a memory task. The results of these three experiments support the predictions derived from models of cognition emphasizing the importance of stimulus organization in the generation and maintenance of task focus and have potential importance for the scientific evaluation of cognition. (shrink)

Most ?theories of consciousness? are based on vague speculations about the properties of conscious experience. We aim to provide a more solid basis for a science of consciousness. We argue that a theory of consciousness should provide an account of the very processes that allow us to acquire and use information about our own mental states ? the processes underlying introspection. This can be achieved through the construction of information processing models that can account for ?Type-C? processes. Type-C processes can (...) be specified experimentally by identifying paradigms in which awareness of the stimulus is necessary for an intentional action. The Shallice (1988b) framework is put forward as providing an initial account of Type-C processes, which can relate perceptual consciousness to consciously performed actions. Further, we suggest that this framework may be refined through the investigation of the functions of prefrontal cortex. The formulation of our approach requires us to consider fundamental conceptual and methodological issues associated with consciousness. The most significant of these issues concerns the scientific use of introspective evidence. We outline and justify a conservative methodological approach to the use of introspective evidence, with attention to the difficulties historically associated with its use in psychology. (shrink)

It has been suggested that the difference between misremembering (Orwellian) and misrepresentation (Stalinesque) models of consciousness cannot be differentiated (Dennett, 1991). According to an Orwellian account a briefly presented stimulus is seen and then forgotten; whereas, by a Stalinesque account it is never seen. At the same time, Dennett suggested a method for assessing whether an individual is conscious of something. An experiment was conducted which used the suggested method for assessing consciousness to look at Stalinesque and Orwellian distinctions. A (...) visual illusion, illusory line motion, was presented and participants were requested to make judgments that reflected what they were aware of. The participants were able to make responses indicating that they were aware of the actual stimulus in some conditions, but only of the illusion in others. This finding supports a claim that the difference between the Orwellian and Stalinesque accounts may be empirically observable, and that both types of events may occur depending on task and stimulus parameters. (shrink)