In this dual-task study we applied both crosstalk logic and locus of slack logic to test whether participants can retrieve semantic categories in Task 2 in parallel to Task 1 bottleneck processing. Whereas crosstalk logic can detect parallel memory retrieval only in conditions of categorical overlap between tasks, the locus of slack approach is independent of such restrictions. As expected, using the crosstalk logic we found clear evidence for parallel retrieval of semantic categories when there was categorical overlap between tasks (Experiment 1). Locus of slack based evidence for parallel semantic retrieval was found, however, both in conditions with (Experiment 1) and without categorical overlap between tasks (Experiment 2). Crucially, however, increasing the demand for resources required to switch from Task 1 to Task 2 eliminated even the locus of slack based evidence for parallel memory retrieval in PRP (Experiment 3). Together, our results suggest that parallel retrieval is not bound to conditions of categorical overlap between tasks, but instead is contingent upon resources needed for switching between tasks (e.g., Oriet et al. 2005).