Summary. When participants have to shift between four tasks that result from a factorial combination of the task dimensions judgment (numerical vs. spatial) and mapping (compatible vs. incompatible), a characteristic profile of shift costs can be observed that is suggestive of a hierarchical switching mechanism that operates upon a dimensionally ordered task representation, with judgment on the top and the response on the bottom of the task hierarchy ( Kleinsorge & Heuer, 1999 ). This switching mechanism results in unintentional shifts on lower levels of the task hierarchy whenever a shift on a higher level has to be performed, leading to non-shift costs on the lower levels. We investigated whether this profile depends on the way in which the individual task dimensions are cued. When the cues for the task dimensions were exchanged, the basic pattern of shift costs was replicated with only minor modifications. This indicates that the postulated hierarchical switching mechanism operates independently of the specifics of task cueing.
Basic Pattern Graphs for the Efficient Computation of Its Number of Independent Sets
