Abstract
Theories of attention suggest that objects represented in visual working memory will automatically guide attention to memory matching items (Desimone & Duncan, 1995). Empirical tests of this proposition have shown mixed results, with some studies showing increases in response time to the search array when a memory matching item is present in the array (e.g., Soto, Heinke, Humphreys, & Blanco, 2005) while others show no effect or a RT benefit when memory matches are present in the search array (e.g., Downing & Dodds, 2004). One possible explanation for these disparate results comes from the suggestion of Woodman & Luck (2007) that the contents of working memory can be used flexibly, or strategically, based on task demands. In the current experiment, we extend prior paradigms by recording eye movements during the task to directly measure overt attention. In addition, we compared a baseline session to an instructional condition in subjects were told either to emphasize speed in the search task or accuracy in the memory task. Results from behavioral and eye-tracking data converge to suggest that the instructions lead to differences in strategy based on whether search speed or memory accuracy was emphasized. These results add support to the hypothesis that working memory guidance of attention is flexible and under strategic control as suggested by Woodman and Luck (2007).
Desimone, R., & Duncan, J. (1995). Annual Review of Neuroscience, 18, 193-222.
Downing, P. E., & Dodds, C. M. (2004). Visual Cognition, 11, 689-703.
Soto, D., Heinke, D., Humphreys, G. W., & Blanco, M. J. (2005). Journal of Experimental Psychology: Human Perception and Performance, 31(2), 248-261.
Woodman, G. F., & Luck, S. J. (2007). Journal of Experimental Psychology: Human Perception and Performance, 33, 363-377.
Vanderbilt Vision Research Center Vanderbilt Center for Integrative and Cognitive Neuroscience.