Abstract
Representations that are actively held in mind guide attention towards matching items in the environment. However, recent work suggests that attention can be guided towards items that do not exactly match the item in memory. For example, when the color red is maintained, even if it is maintained very precisely, attention is nonetheless guided towards similar items like pink. This has been taken as evidence that the template which guides attention is more broadly tuned (i.e., less precise), and thus distinct from the corresponding memory representation. Here, we test a strong prediction of the ‘fidelity model’ of guidance proposed by Williams, Brady and Stoermer (2022) which predicts that attention should be guided to a broader range of items than memory errors would suggest. This is because when items are encoded into memory, similar items are automatically activated and while memory errors are based only on the maximally activated item, guidance is not. Furthermore, as memory representations gain strength, similar items are also more strongly activated, leading to more guidance for these similar items while simultaneously leading to a smaller distribution of memory errors. In a series of simulations and an experiment (N=75), we confirm these predictions, showing evidence consistent with the model’s claim that memory responses are necessarily more precise than guidance. Additionally, this model accurately predicts the amount of guidance that occurs when the similarity between the encoded item and the target item decreases. Overall, we show that the fidelity model inherently predicts guidance for non-matching, similar items and that, perhaps paradoxically, the amount of guidance for these items should increase when memory strength is high. Thus, we show that the data which has been taken as a strong dissociation between attention and memory is surprisingly consistent with both of these mechanisms sharing the same underlying representation.