Jessica Kespe¹, Marielle Noack¹, Naseem Al-Aidroos¹; ¹University of Guelph

When observers are shown a visual target to later search for, they form an attentional template—¬a mental representation of the target’s features. This template acts as a guide, allowing only stimuli that match the target’s features to capture attention. Recent research has shown that templates stored in visual working memory (VWM) do not only reflect the target object that was shown to the observer, but also features from long-term memory (LTM) that were previously associated with that object. For example, if a shape was previously associated with a specific colour, that association can be retrieved and represented in VWM, even in the absence of direct visual input: a process termed LTM reinstatement. Interestingly, reinstated features in VWM can prefentially capture attention even when they are task irrelevant. How long do you need to see an object for task-irrelevant features from LTM to be reinstated, and how long do you need to actively maintain that feature in VWM to see the attentional effects? To investigate both questions, participants memorized a set of objects with specific colours and then completed a search task where they were instructed to search for one of the memorized objects’ shapes in any colour. We manipulated how long participants saw the search target object (Exp 1) and how long they had to hold the target in VWM before the search task started (Exp 2). We found that participants needed to see the object for a minimum of about 50ms, and then maintain it in VWM for another 50ms, for LTM reinstatement to later occur. These results highlight the rapid interaction between LTM and VWM, suggesting that even brief perceptual exposure and VWM maintenance can trigger the reinstatement of task-irrelevant features.

Acknowledgements: NSERC Grant to Naseem Al-Aidroos and Jessica Kespe