title: Visual salience improves spatial working memory via enhanced parieto-temporal functional connectivity.
abstract: In everyday life, the brain is bombarded with a multitude of concurrent and competing stimuli. Only some of these enter consciousness and memory. Attention selects relevant signals for in-depth processing depending on current goals, but also on the intrinsic properties of stimuli. We combined behavior, computational modeling, and functional imaging to investigate mechanisms supporting access to memory based on intrinsic sensory properties. During fMRI scanning, human subjects were presented with pictures of naturalistic scenes that entailed high levels of competition between possible target objects. Following a retention interval of 8 s, participants judged the location (same/different) of a target object extracted from the initial scene. We found that memory performance at retrieval increased with increasing object salience at encoding, indicating a "prior entry" for salient information. fMRI analyses revealed encoding-related activation in the posterior parietal cortex, selectively for salient objects that were later remembered. Moreover, parietal cortex showed increased functional coupling with the medial-temporal lobe, for remembered objects only. These findings reveal a parietotemporal circuit that integrates available sensory cues (based on attention-grabbing saliency signals) and current memory requirements (storing objects' locations) to encode object-related spatial information in working memory.
authors: Department of Human and Educational Sciences, University of Perugia, 06123 Perugia, Italy. valerio.santangelo@unipg.it
authors: Valerio
authors: V
authors: Santangelo
authors: Emiliano
authors: E
authors: Macaluso
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001931:Brain Mapping; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D011939:Mental Recall; D010100:Oxygen / Q000097:blood; D010296:Parietal Lobe / Q000098:blood supply / Q000502:physiology*; D010775:Photic Stimulation; D011930:Reaction Time; D012858:Size Perception / Q000502:physiology*; D013028:Space Perception / Q000502:physiology*; D013702:Temporal Lobe / Q000098:blood supply / Q000502:physiology*; D014795:Visual Pathways / Q000098:blood supply / Q000502:physiology; D055815:Young Adult
chemical_list: D010100:Oxygen