UNIGE document Scientific Article
previous document  unige:10499  next document
add to browser collection
Title

Selective attention modulates neural substrates of repetition priming and "implicit" visual memory: suppressions and enhancements revealed by FMRI

Authors
Duhoux, Stephanie
Dolan, R. J.
Driver, Jon
Published in Journal of Cognitive Neuroscience. 2005, vol. 17, no. 8, p. 1245-1260
Abstract Attention can enhance processing for relevant information and suppress this for ignored stimuli. However, some residual processing may still arise without attention. Here we presented overlapping outline objects at study, with subjects attending to those in one color but not the other. Attended objects were subsequently recognized on a surprise memory test, whereas there was complete amnesia for ignored items on such direct explicit testing; yet reliable behavioral priming effects were found on indirect testing. Event-related fMRI examined neural responses to previously attended or ignored objects, now shown alone in the same or mirror-reversed orientation as before, intermixed with new items. Repetition-related decreases in fMRI responses for objects previously attended and repeated in the same orientation were found in the right posterior fusiform, lateral occipital, and left inferior frontal cortex. More anterior fusiform regions also showed some repetition decreases for ignored objects, irrespective of orientation. View-specific repetition decreases were found in the striate cortex, particularly for previously attended items. In addition, previously ignored objects produced some fMRI response increases in the bilateral lingual gyri, relative to new objects. Selective attention at exposure can thus produce several distinct long-term effects on processing of stimuli repeated later, with neural response suppression stronger for previously attended objects, and some response enhancement for previously ignored objects, with these effects arising in different brain areas. Although repetition decreases may relate to positive priming phenomena, the repetition increases for ignored objects shown here for the first time might relate to processes that can produce "negative priming" in some behavioral studies. These results reveal quantitative and qualitative differences between neural substrates of long-term repetition effects for attended versus unattended objects.
Keywords AdultAttention/ physiologyCerebral Cortex/physiologyColor Perception/physiologyCuesFemaleFunctional Laterality/physiologyHumansImage Interpretation, Computer-AssistedLinear ModelsMagnetic Resonance ImagingMaleMemory/ physiologyNeurons/ physiologyOrientation/physiologyPhotic StimulationPsychomotor Performance/physiologyVisual Perception/ physiology
Stable URL http://archive-ouverte.unige.ch/unige:10499
Full text
Identifiers
PMID: 16197681
Structures
121 hits and 0 download since 2010-08-06
Update
Export document
Format :
Citation style :