DISTRACTOR SUPPRESSION & MEMORY 1 Not All Attention Orienting is Created Equal : Recognition Memory is Enhanced When Attention Orienting Involves Distractor Suppression

Learning through visual exploration requires orienting of attention to meaningful information in a cluttered world. Previous work has shown that attention modulates visual cortex activity, with enhanced activity for attended targets and suppressed activity for competing inputs, thus enhancing the visual experience. We hypothesized that attention orienting mechanisms that engage concurrent suppression of competing locations will lead to more effective memory encoding and subsequent recognition memory as a result of a reduction in noise interfering with the visual representation for the attended objects. This examination thus sheds light on how learning may be engaged differentially with variations in attention orienting mechanisms underlying eye movement executing during visual search and exploration. To test this hypothesis we capitalized on the classic spatial cueing task and the inhibition of return (IOR) mechanism (Posner, 1980; Posner, Rafal, Choate, & Vaughan, 1985) to demonstrate that object images encoded in the context of concurrent distractor suppression were encoded more effectively and remembered better than those encoded without concurrent suppression. Furthermore, fMRI analyses revealed that this memory benefit was driven by attention modulation of visual cortex activity, as increased suppression of the previously attended location in visual cortex during target object encoding predicted better subsequent recognition memory accuracy. These results suggest that not all attention orienting impacts learning and memory equally. Rather, orienting mechanisms that engage suppression, indexed here as suppression of the previously attended location (IOR), boost memory encoding to a greater extent than those that involve target enhancement alone.