the total demand for processing resources exceeds the available supply. Modular theories predict that interference occurs only to the extent that concurrent tasks compete for the same module, e.g., two tasks that both demand visuospatial resources.

More formal resource models of mental workload distinguish between data-limited and resource-limited processes. According to this view, which assumes that resources are unitary, there are different ways in which the availability of resources can influence the functioning of simultaneously active mental processes. Once a certain minimum level of resources is allocated to activate a mental process, the application of greater resources leads to more efficient (e.g., faster, more accurate) execution of that process. Such a process is said to be resource-limited, in that the quality of its output is dependent on the allocation of resources. Subjectively, "working harder'' at a task will improve its performance. As more resources are applied, however, there may come a point at which further allocation no longer improves the efficiency of the mental process. At this point, performance is said to be data-limited; efficiency is determined by the quality of the input source to the process, whether that source is sensory or drawn from memory storage (see Fig. 5). The subjective experience is that when the stimulus input is degraded, performance cannot be bettered: for example, no amount of "trying harder'' will improve one's perception of a weak sound buried in loud noise.

Breaking Bulimia

Breaking Bulimia

We have all been there: turning to the refrigerator if feeling lonely or bored or indulging in seconds or thirds if strained. But if you suffer from bulimia, the from time to time urge to overeat is more like an obsession.

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