Long-term memory prepares neural activity for perception.

Stokes MG., Atherton K., Patai EZ., Nobre AC.

Past experience provides a rich source of predictive information about the world that could be used to guide and optimize ongoing perception. However, the neural mechanisms that integrate information coded in long-term memory (LTM) with ongoing perceptual processing remain unknown. Here, we explore how the contents of LTM optimize perception by modulating anticipatory brain states. By using a paradigm that integrates LTM and attentional orienting, we first demonstrate that the contents of LTM sharpen perceptual sensitivity for targets presented at memory-predicted spatial locations. Next, we examine oscillations in EEG to show that memory-guided attention is associated with spatially specific desynchronization of alpha-band activity over visual cortex. Additionally, we use functional MRI to confirm that target-predictive spatial information stored in LTM triggers spatiotopic modulation of preparatory activity in extrastriate visual cortex. Finally, functional MRI results also implicate an integrated cortical network, including the hippocampus and a dorsal frontoparietal circuit, as a likely candidate for organizing preparatory states in visual cortex according to the contents of LTM.

DOI

10.1073/pnas.1108555108

Type

Journal article

Journal

Proc Natl Acad Sci U S A

Publication Date

07/02/2012

Volume

109

Pages

E360 - E367

Keywords

Adult, Attention, Brain, Cortical Synchronization, Electrodes, Female, Humans, Magnetic Resonance Imaging, Male, Memory, Long-Term, Nerve Net, Orientation, Oxygen, Visual Perception

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