Visual selection is served by attentional templates, which are memory representations of task-relevant (target) information. Recent studies using cued visual search tasks in combination with electrophysiological markers of visual working memory (VWM) suggest that observers initially keep the template in VWM but then rapidly offload it to long-term memory (LTM) when the target repeats. The present study uses eye-tracking to investigate if the oculomotor system can also provide useful markers of attentional learning. Participants first received a cue as to which target to look for in a subsequent search display, which was presented after an approximately one second delay. Search displays consisted of Landolt Cs with gaps in eight possible orientations. The same target was then repeated for another six trials, as was the cue indicating the target identity. After seven trials in total, observers received a new cue indicating the new target, which was then repeated again. Crucially, the cues were presented lateralized and were so small that observers had to make an eye movement to discern it. If learning leads to a shift from VWM to LTM, then it becomes unnecessary to look at the cue, predicting a reduction in cue-directed saccades. However, this is not what happened: Although a speeding of search RTs indicated learning with target repetition, saccade rates to the cue hardly decreased. Instead, repetition of the cue led to a decrease in fixation duration on the cue. Making processing of the cue more costly (using symbolic cues) or even useless (using completely uninformative cues) led at best to a moderate decrease in saccadic orienting to the cue. The results indicate that fixation duration is a more reliable marker of cue-based attentional learning than saccadic orienting is. Instead, saccadic orienting may be used to retrieve learned memories, using the cue as an "external pointer".
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