Parietal cortex integrates contextual and saliency signals during the encoding of natural scenes in working memory.
The Brief presentation of a complex scene entails that only a few objects can be selected, processed indepth, and stored in memory. Both low-level sensory salience and high-level context-related factors (e.g., the conceptual match/mismatch between objects and scene context) contribute to this selection process, but how the interplay between these factors affects memory encoding is largely unexplored. Here, during fMRI we presented participants with pictures of everyday scenes. After a short retention interval, participants judged the position of a target object extracted from the initial scene. The target object could be either congruent or incongruent with the context of the scene, and could be located in a region of the image with maximal or minimal salience. Behaviourally, we found a reduced impact of saliency on visuospatial working memory performance when the target was out-of-context. Encoding-related fMRI results showed that context-congruent targets activated dorsoparietal regions, while context-incongruent targets de-activated the ventroparietal cortex. Saliency modulated activity both in dorsal and ventral regions, with larger context-related effects for salient targets. These findings demonstrate the joint contribution of knowledge-based and saliency-driven attention for memory encoding, highlighting a dissociation between dorsal and ventral parietal regions.
Neuroimaging Laboratory, Santa Lucia Foundation, Rome, Italy.|Department of Philosophy, Social Sciences and Education, University of Perugia, Perugia, Italy.
Valerio
V
Santangelo
Neuroimaging Laboratory, Santa Lucia Foundation, Rome, Italy.|Department of Psychology, "Sapienza" University of Rome, Rome, Italy.
Simona Arianna
SA
Di Francesco
Neuroimaging Laboratory, Santa Lucia Foundation, Rome, Italy.
Serena
S
Mastroberardino
Neuroimaging Laboratory, Santa Lucia Foundation, Rome, Italy.
Emiliano
E
Macaluso
D000328:Adult; D000704:Analysis of Variance; D001288:Attention; D001931:Brain Mapping; D003463:Cues; D005133:Eye Movements; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D010100:Oxygen / Q000097:blood; D010296:Parietal Lobe / Q000098:blood supply / Q000502:physiology*; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology; D055815:Young Adult
D010100:Oxygen
attention; context; fMRI; natural scenes; parietal cortex; saliency; working memory