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Gamma flicker triggers attentional selection without awareness.

ABSTRACT: Gamma band modulations in neural activity have been proposed to mediate attentional processes. To support a causal link between gamma activity and attentional selection, we attempt to evoke gamma oscillations by a 50-Hz subliminal flicker. We find that a subliminal 50-Hz flicker at a target location, before target presentation, speeds up and enhances target detection and discrimination. This effect is specific to the middle of the gamma range because it is not evident at <35-Hz flicker. It requires 300 ms to build up, dissipates within 250 ms of flicker offset, and shows a tendency to invert after 500 ms. The results are discussed in relation to a role for gamma band neural synchrony in the allocation of visual attention.

SUBMITTER: Bauer F

PROVIDER: S-EPMC2635817 | biostudies-other | 2009 Feb

REPOSITORIES: biostudies-other

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Gamma flicker triggers attentional selection without awareness.

Bauer Frank F Cheadle Samuel W SW Parton Andrew A Müller Hermann J HJ Usher Marius M

Proceedings of the National Academy of Sciences of the United States of America 20090105 5

Gamma band modulations in neural activity have been proposed to mediate attentional processes. To support a causal link between gamma activity and attentional selection, we attempt to evoke gamma oscillations by a 50-Hz subliminal flicker. We find that a subliminal 50-Hz flicker at a target location, before target presentation, speeds up and enhances target detection and discrimination. This effect is specific to the middle of the gamma range because it is not evident at <35-Hz flicker. It requi ...[more]

PMID: 19124766

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