The lateral intraparietal sulcus takes viewpoint changes into account during memory-guided attention in natural scenes

Ilenia Salsano (1) , Valerio Santangelo (2) , Emiliano Macaluso (3)

1 UNIROMA - Università degli Studi di Roma "La Sapienza" = Sapienza University [Rome]
2 UNIPG - Università degli Studi di Perugia = University of Perugia
3 CRNL - Centre de recherche en neurosciences de Lyon - Lyon Neuroscience Research Center

Abstract Previous studies demonstrated that long-term memory related to object-position in natural scenes guides visuo-spatial attention during subsequent search. Memory-guided attention has been associated with the activation of memory regions (the medial-temporal cortex) and with the fronto-parietal attention network. Notably, these circuits represent external locations with different frames of reference: egocentric (i.e., eyes/head-centered) in the dorsal attention network vs. allocentric (i.e., world/scene-centered) in the medial temporal cortex. Here we used behavioral measures and fMRI to assess the contribution of egocentric and allocentric spatial information during memory-guided attention. At encoding, participants were presented with real-world scenes and asked to search for and memorize the location of a high-contrast target superimposed in half of the scenes. At retrieval, participants viewed again the same scenes, now all including a low-contrast target. In scenes that included the target at encoding, the target was presented at the same scene-location. Critically, scenes were now shown either from the same or different viewpoint compared with encoding. This resulted in a memory-by-view design (target seen/unseen x same/different view), which allowed us teasing apart the role of allocentric vs. egocentric signals during memory-guided attention. Retrieval-related results showed greater search-accuracy for seen than unseen targets, both in the same and different views, indicating that memory contributes to visual search notwithstanding perspective changes. This view-change independent effect was associated with the activation of the left lateral intra-parietal sulcus. Our results demonstrate that this parietal region mediates memory-guided attention by taking into account allocentric/scene-centered information about the objects' position in the external world.

Mots clés: fMRI; Attention; Long-term memory; Intraparietal sulcus; Natural scenes; Visual search

Domaines: Sciences cognitives

Ilenia Salsano, Valerio Santangelo, Emiliano Macaluso. The lateral intraparietal sulcus takes viewpoint changes into account during memory-guided attention in natural scenes. Brain Structure and Function, 2021, 226 (4), pp.989-1006. ⟨10.1007/s00429-021-02221-y⟩. ⟨hal-03935214⟩